# Experimental German planes



## J dog (Dec 20, 2012)

Ok Let's say the Germans won WW2 and the Korean war still happened no matter any world changes after that. Would the German experimental planes or fastest planes be capable of taking on MiG -15s or Sabres? This is not me saying that the Germans could win the war though this is just me asking a question. Please comment and please make things appropriate and respectful towards others opinions!


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## Jack_Hill (Dec 20, 2012)

I guess, if Germany had won WWII, MiG15 and F86 would simply not even had ever existed.
A kind of Tank, Messerschmitt, Junker, Dornier, etc...monopole should have take place instead.


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## A4K (Dec 21, 2012)

Exactly. The MiG 15 was a culmination of development of the Fw Ta 183 design, and the swept wings of the F-86 were results of testing Me 262 wings- they were originally designed in usual straight wing format.


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## J dog (Dec 21, 2012)

Ok I should have been more clear. Let's say against all the odds these planes were still created no matter the changes Germany made. I know that these would have no chance because Germany would have kept a tight shift and banned the making of war planes. That aside all the planes were to still be made and another war was started Germany's planes vs Sabre and Mig 15 and all the other Mig and Us jet and prop fighters would they have the speed, agility and altitude to duel with these planes. Just ignore anything outside like the developement and the rules and just focus on the planes themselves. Just ignore all of the obvious and focus on their performence.


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## J dog (Dec 21, 2012)

sorry!


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## Jack_Hill (Dec 21, 2012)

Then, yes, even if your proposal is a really severe "what if". Imaginating German industry having continue to develop, at this times, some very high performances a/c, it could give : close to, or supersonic aircrafts. 
Reliable, powerfull afterburning engines.
Highly modern, clean aerodynamics with reasonnable (or more) maniability.
Hard hitting, very high RoF and accuracy canons, coupled with high precision (at last) gyro (+radar ?) gunsights.
hard hitting, low to medium range self guided missiles. 
Kind of fully operational Me P-1101, Ho229, He162 or Ta183 indeed.
Or better, depending on politics and budgets.
We can too imagine such fighter aircrafts Geschwaders under, say, Erich Hartmann, heinz Barr or Adolf Galland command.
But not against MiG15 or F86. 
Meteors, F80, maybe better...
Other than German techs would have rushed reaching the level by this time and, why not, with success, with many skilled, experienced pilots and leaders too...


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## R Pope (Dec 21, 2012)

Given such a scenario, I would think the German aircraft industry would have made similar forward strides and developed second and third generation planes as capable as the Sabre and Mig, which were, after all, second generation jets themselves, based on captured German first gen planes.


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## Wurger (Dec 29, 2012)

A moved thread from another section....


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## wuzak (Dec 29, 2012)

If the Germans win the war then the Soviets have been defeated, so there will be no Soviet aircraft industry. I suppose it also means that the UK is occupied, and the US is also subjugated.

How the latter could happen I don't know. The US were developing platforms such as the B-36 for the eventuality that the UK fell to Germany, and bombing missions would have to be flown from the continental USA.

I suppose Germany winning the war would help Japan keep capture territories in South East Asia. And even if they were kicked out by the US, the Soviets had been defeated by Germany, so Korea would not have been divided into north and south and there would be no Korean war.


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## davebender (Dec 29, 2012)

SNECMA Atar - Wikipedia, the free encyclopedia
If Germany remains a sovereign nation I assume BMW would continue development of BMW003 engine and follow on design would look a lot like the SNECMA Atar. BMW engine would compete with HeS 011 and advanced versions of Jumo 004 for contract to power the new swept wing German fighter aircraft.


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## GrauGeist (Dec 30, 2012)

The F-86 and the MiG-15 definately would have never happened if the Germans avoided being defeated. But then again, the Korean war would have never happened then, either. Korea was the result of the unrest perpetuated by occupying Japanese forces and the Communist Chinese would have been busy fighting the Japanese occupation and the Chinese Nationalists, not invading (assumably still Japanese occupied) Korea.

However, it would be interesting to see how the Luftwaffe's aircraft developed at the rate they were going. The Me262A1a was Willy's first step towards the 262's eventual goal, the Me262 HGIII. There were also some very modern designs in the development stages from several manufacturers that held alot of promise: He P.1079a, Fw Projekt VII "Flitzer", Bv P.211.01, Me P.1100/II, Junkers jet-powered ground attack (un-named) project to replace the Hs129, Do P.256 and of course, the ones that were in service or nearly in service by war's end.

Then again, the Japanese were on the verge of having jet aircraft as well (Nakajima Kikka, KI-201, etc)

The skies would have certainly been different.


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## tyrodtom (Dec 30, 2012)

Just because Germany was ahead in swept wing research in 1944-45 doesn't mean no one else couldn't do some study of it also.
Once WW2 was over, and the Allies had access to a lot of German research information, it saved them a lot of time and money, but that doesn't mean it couldn't have been done without that German research.


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## Shortround6 (Dec 30, 2012)

The Americans and British not only had large aircraft industries, by 1944/45 they had large research establishments (not always the same thing). Once their own jet fighters ran into drag problems in the 500+ mph range and they noticed German aircraft with swept wings they would have tried models in their wind tunnels and found out pretty quickly why the Germans were using swept wings. The Americans would have caught up to the Germans pretty quickly. Not because the Americans were any smarter but because the Americans would have had a lot more people working on the projects. The population of Germany in 1940 (including annexed Austria, Memelland, and the Sudetenland) was just over 80 million. The population of the US in 1940 was about 132 million. Throw in the populations of England and the British commonwealth and the Allies had a lot more people to draw engineers and research people from. 
Just when in the years from 1945 to 1950 the F-86 would have appeared may be subject to debate but the US and Britain would not be using (or planning) solely straight wing aircraft in 1949/50.


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## delcyros (Dec 30, 2012)

Swept wing research was publicly aviable due to the conference in Rome just prior the outbreak of ww2. Unfortunately, nobody noticed it until beeing forced to by reaching the transsonic realm. Even then it caused a lot of problems, representing basically a tradeoff between low-speed and high-speed realm. What You gain in the high speed realm, the layout has to give up in the low speed realm, complicating the technical application of swept wings. It requires sound structural design and use of very sophisticated high lift aids to work.
The allies were certainly capable to develop their own solutions on that. It may have required more time and money and thus may give an initial lead to the Luftwaffe but there cannot be a doubt that this would only be temporary.
US procurement policy was to prefer the P-80A as initial jet of late 1945/1946 to be augmented by Republics XP-86 which would appear not before 1947 in numbers. Its not entirely clear that the NA XP-86 (straight wing version) would have continued as the prototype didn´t provided for more speed than the existing P-80 and XP-84, which also had the benefit of beeing more advanced in stage of development.
The UK was preferring the Meteor and Vampire. However, any design on the drawing board intended to replace these A/C likely would have benefitted from swept wing designs. Critical Mach speed was the most limiting factor and thus, it is reasonable to assume the allies to concentrate their efforts to delete this obstacle and I cannot see why we should assume that they should be incapable of it.

I personally don´t think that population represents a useful measurement for engeneering questions in this timeframe. Otherwise China would be cutting edge. It´s a question of how many engeneerers were aviable and how skilled they were. Also how much basic theory had been worked out, and of course, how many ressources were directed to these efforts.


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## davebender (Dec 30, 2012)

I would not make that assumption. We are cutting edge in some areas and rather backward in other areas.

For example, how many years were required for American small arms to catch up with MG42 machinegun? One could argue we still haven't as our current M240 and M249 machineguns were both designed by Fabrique Nationale.


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## GrauGeist (Dec 30, 2012)

Another point regarding the Allied Jet designs...look at thier aircraft designs both existing and experimental before they were able to capture the German's designs and test data. The years directly following the defeat of the Axis saw a leap in Allied aircraft design for a reason.


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## Shortround6 (Dec 30, 2012)

delcyros said:


> I personally don´t think that population represents a useful measurement for engeneering questions in this timeframe. Otherwise China would be cutting edge. It´s a question of how many engeneerers were aviable and how skilled they were. Also how much basic theory had been worked out, and of course, how many ressources were directed to these efforts.



If you have populations that are educated to _about_ the same level it provides a reference point or frame work. Obviously 100 million people (or more) who are effectively illiterate (no matter how intelligent) do not offer much help. With the US population about 60% higher than the greater German population it would take a much higher average education in Germany to over balance the population difference. 
The population is also an indicator (one of many) of how many resources are available. You not only need _lead_ engineers ( or idea men) but hundreds if not thousands of background engineers/draftsmen/calculators to turn the ideas into reality. Without computers all stress analysis and other calculations were done by rows of engineers (low level) sitting at desks with adding machines and slide rules. 

The US had gone from about 12/13 wind tunnels prewar to about 40 by the end of the war with many of them located at collages and universities.


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## fastmongrel (Dec 30, 2012)

You only have to look at the work that companies like Miles and Bell did to realise that any lead the Germans had would have been only temporary. Allied research was concentrated on refining the weapons that were winning the war, the Germans were desperately looking for a wonder weapon that would stop them losing. 

Desperation will do wonders for ingenuity if the boot had been on the other foot I am sure a Miles Sparrowhawk Mk1a powered by a Rolls Royce afterburning Nene and carrying Red Flash Missiles would have been flying pretty quick.


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## oldcrowcv63 (Dec 30, 2012)

tyrodtom said:


> Just because Germany was ahead in swept wing research in 1944-45 _*doesn't mean no one else couldn't do some study of it also*_.
> Once WW2 was over, and the Allies had access to a lot of German research information, it saved them a lot of time and money, but that doesn't mean it couldn't have been done without that German research.


 


Shortround6 said:


> The Americans and British not only had large aircraft industries, by 1944/45 they had _*large research establishments *_(not always the same thing). Once their own jet fighters ran into drag problems in the 500+ mph range and they noticed German aircraft with swept wings they would have tried models in their wind tunnels and found out pretty quickly why the Germans were using swept wings. The Americans would have caught up to the Germans pretty quickly. Not because the Americans were any smarter but because the Americans would have had a lot more people working on the projects. The population of Germany in 1940 (including annexed Austria, Memelland, and the Sudetenland) was just over 80 million. The population of the US in 1940 was about 132 million. Throw in the populations of England and the British commonwealth and the Allies had a lot more people to draw engineers and research people from.
> Just when in the years from 1945 to 1950 the F-86 would have appeared may be subject to debate but the US and Britain would not be using (or planning) solely straight wing aircraft in 1949/50.





davebender said:


> I would not make that assumption. We are _*cutting edge in some areas and rather backward in other areas*_.



I think these are good points. It is my understanding that the foremost aspect of the German contribution to the adoption of swept wing technology was the experimental data they had accumulated in wind tunnels flight tests and operations. Wikipedia states that in early 1945 NACA engineer R.T. Jones duplicated the German theoretical work reported in 1935 by German engineer Buseman in Italy. By May 1945, wind tunnel models had shown that swept wings produced a significant drag reduction. I don't know whether this was duplicated in Britain but it does appear they adopted the technology very rapidly. Not terribly surprising considering their own seminal work in the area of jet engines and propelled aircraft was nearly apace with the Reich's while establishing the basis for US work in the field.

In the context of german vs allied technology and research, I am not sure _*backward *_in some ares is quite accurate. I would perhaps say more resistant to deviate from what appeared to be more promising paths. Recips and straight wings still seemed to be showing some promise in the high speed to transonic realm, including greater endurance and acceleration and also performance that exceeded early jets and apparently that approaching the faster second generation (262). The XP-47J coming within ~40 mph of the 262, IIRC. The flirtation with hybrid engines was ascendent. Assuming a nazi victory seems a stretch considering the US had the bomb at the end and the reich's research was floundering. I could more easily imagine a drawn out war with the US attempting to liberate an occupied Europe or some sort of negotiated truce or cease fire with England surviving unoccupied. The straight winged P-80 is typically reported as having double the legs of the Me-262 and a similar speed. While it was perhaps a tad slower in its earliest incarnation, the P-80 had a much shorter development period had not yet achieved its full potential while the 262 had been operational for a longer period and was suffering from the deprivation brought about due to its war torn axis environment. In the event that there was a delay in the war's conclusion and time and material for continued development of both aircraft, the results would have been interesting but I believe that prospect has been beaten to death in the pages of the forum.


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## delcyros (Dec 31, 2012)

Shortround6 said:


> If you have populations that are educated to _about_ the same level it provides a reference point or frame work. Obviously 100 million people (or more) who are effectively illiterate (no matter how intelligent) do not offer much help. With the US population about 60% higher than the greater German population it would take a much higher average education in Germany to over balance the population difference.
> The population is also an indicator (one of many) of how many resources are available. You not only need _lead_ engineers ( or idea men) but hundreds if not thousands of background engineers/draftsmen/calculators to turn the ideas into reality. Without computers all stress analysis and other calculations were done by rows of engineers (low level) sitting at desks with adding machines and slide rules.
> 
> The US had gone from about 12/13 wind tunnels prewar to about 40 by the end of the war with many of them located at collages and universities.



Actually, this is more or less speculative what You wrote. As I said, not the whole population but the size of the technological ressources is important, particularely that devoted primarely for aerodynamic research. You need to work out the number of those employed in the US and Germany in this field to get an idea about this. It takes years to train an aeronautical engeneerer, not months. It takes a great deal of expertise in addition to academic training to become a contributing engeneerer in aeronautic industries. Finally, it takes ressources and the correct decision of research question to extract meaningful results. Population, even literate population is not a helpful indicator for a rapid catchup in cutting edge technology, sorry, I don´t buy this idea.

Wrt wind tunnels, for the issues under question in high speed aircraft, You don´t need 40 subsonic wind tunnels, You need windtunnels operating in the transsonic and supersonic realm. Germany was in posession of them, the NACA not until it ot access to german ones and established it´s first domestic one in the late 40´s.


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## delcyros (Dec 31, 2012)

edit: The first domestic one went online before 1951, but the NACA buildt up several german trans- and supersonic windtunnels on US ground and had them in operation by 1947. These were crucial in confirming the german swept wing and area rule theories.


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## oldcrowcv63 (Dec 31, 2012)

delcyros said:


> edit: The first domestic one went online before 1951, but the NACA buildt up several german trans- and supersonic windtunnels on US ground and had them in operation by 1947. These were crucial in confirming the german swept wing and area rule theories.



LIke so many posts in the forum, this one is both enlightening and perhaps subject to the devils in the pesky details. 

It looks like NACA was strong-armed by Hap Arnold to create a number of borderline or transitional or nearly transonic-capable wind tunnels due to the P-38's problem with compressibility. Once again from wiki:

"_...NACA's 1941 refusal to increase airspeed in their wind tunnels set Lockheed back a year in their quest to solve the problem of compressibility. 

The full-size 30-by-60-foot (9.1 m × 18 m) Langley wind tunnel operated at no more than 100 miles per hour (160 km/h) and the recent 7-by-10-foot (2.1 m × 3.0 m) tunnels at Moffett could only reach 250 mph (400 km/h). These were speeds Lockheed engineers considered useless for their purposes. Gen. 'Hap' Arnold took up the matter and overruled NACA objections to higher air speeds. *NACA built a handful of new high-speed wind tunnels, and Mach 0.75 (570 mph, 920 km/h) was reached at Moffett's 16-foot (4.9 m) wind tunnel late in 1942.*_" 

Clearly these can't compare to the innovations implicit in the German's development of large cavern transonic-supersonic wind tunnels but they evidently gave a rudimentary capability to the USAAF/NACA sufficient to test the benefits of the swept wing prior to the end of hostilities. 

Also, with the emergence of the P-80 and British jets it was only a matter of time before either of the two principal allied combatants developed higher speed wind tunnels. The German data and experience was a windfall that seems, in addition to the tangible benefits to programs like the F-86, to have temporarily obviated the need to build faster tunnels during the leanly funded post war research years.


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## oldcrowcv63 (Dec 31, 2012)

Moreover, somewhat like the use of Chaff during WW2, once the cat is out of the bag, in this case in the form of the -262's obviously swept wings, it seems reasonable to me that engineers might very well look at the combat footage and wonder, "Is the wing sweep of that marvelous aircraft just about center-of-gravity considerations or is something else going on here?" Without reading Jones' NACA reports I can't help but wonder if that wasn't a contributing spur for his work.

Ooops chaff a bad analogy since both sides already had it IIRC.


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## Shortround6 (Dec 31, 2012)

oldcrowcv63 said:


> Clearly these can't compare to the innovations implicit in the German's development of large cavern transonic-supersonic wind tunnels but they evidently gave a rudimentary capability to the USAAF/NACA sufficient to test the benefits of the swept wing prior to the end of hostilities.
> 
> Also, with the emergence of the P-80 and British jets it was only a matter of time before either of the two principle allied combatants developed higher speed wind tunnels. The German data and experience was a windfall that seems, in addition to the tangible benefits to programs like the F-86, to have temporarily obviated the need to build faster tunnels during the leanly funded post war research years.



And there is the big problem with many of these post WW II coulda/woulda scenarios. The US was already scaling back programs even before the Japanese surrendered and the cuts after V-J day were truly massive. With the coming of the cold war many programs ramped back up but not at the intensity of most of the war time programs. 
The US areo industry was by far the largest in the world, although in a number of cases it was manufacturing and not true design teams. However even the number of companies involved in design was still quite large. 

Beech
Bell
Boeing
Chance Vought
Consolidated vultee
Curtiss
Douglas
Fairchild
Grumman
Lockheed
MacDonnell
Martin
North American
Northrop
Republic

15 companies not including light plane makers or even Sikorsky and other helicopter makers. 
Any companies (like Curtiss) that went into decline free up engineers and draftsmen for other companies. 

By 1947/48 things were heating back up but still nothing approaching a true war footing. 

Somethings may have been able to be speeded up and some things not. But to say the US and the British Commonwealth could not have increased their development pace over historical is not well founded. 

The German research was a windfall and meant it did not have to be duplicated but given 5 years I think the gap would be narrow if it existed at all.


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## bobbysocks (Dec 31, 2012)

oldcrowcv63 said:


> in this case in the form of the -262's obviously swept wings, it seems reasonable to me that engineers might very well look at the combat footage and wonder, "Is the wing sweep of that marvelous aircraft just about center-of-gravity considerations or is something else going on here?"



thats the way i understood it. the design was to balance the CG on the plane due to the length and weight of the engines, nose armament, and load of the forward fuel cell ( which was needed to give the plane some range ). the fact that the design also help with compressibility issues was not even considered or known when it the plane was drawn up...but discovered later. neither the ar 234 or the he 162 had swept wings.


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## GrauGeist (Dec 31, 2012)

The Me262 HGII/III was intended to have true swept wings (HGII-35°, HGIII-45°), but the Me262A1a's design was only to compensate for CoG (as noted above)...the current Me262 did have problems at high speeds and pilots were warned not to exceed 931kph/578mph (Mach 0.86) in a dive.

As far as American and British jet designs up to the close of WWII, they all had "straight" wing designs which to me, indicated that they hadn't addressed (or worked out a solution for) the compressability problem at that point in time.


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## GregP (Jan 1, 2013)

Graugeist,

Perhaps you forget the Curtiss XP-55. It flew in 1943 and was definitely a swept wing canard design. Maybe also the Northrop P-56 (1943) which was also swept wing, the Northrop N9-M (1942) or the N9-MB (1943), which were also swept wing deisgns.

So the concept was there and would have been explored at SOME time regardless of exposure to German data.


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## GrauGeist (Jan 1, 2013)

XP-55 had "swept" wings because of CoG control, like the Me262, but at speeds of 390mph, it wasn't close to encountering or solving compressability problems...

XP-56 was a terrible project with huge CoG problems. The "swept" wing here was an effort, again, to solve that. The estimated speed of 465 miles an hour were never achieved.

The N-9M/N-9MB (and N-1M) weren't swept wings, they were "delta" style wings (think Horton or Lippische) that were developed during the 20's and 30's in glider designs. The N-9M had a top speed of 258mph and the N-1M was 200 mph.

So I would hardly say the concept was there in relation to the Mach envelope theories, especially if none of these aircraft could get close to it.


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## oldcrowcv63 (Jan 1, 2013)

Seems like the best that can be said is that (some) allied aero engineers had a line on the problem (re Jones cited above) but weren't quite at the aircraft development stage. While the German's had the data and the significant flight experience at high Mach (M>0.70), they also weren't quite at the aircraft development stage either, although closer than the allies.

Straight wings such as on the P-80, were used on the early jets including, for example, the F2H Banshee, F-84 Thunderjet, and F9F Cougar and did pretty well up, to and through much of the Korean War. The Panther did reasonably well even against the Mig 15 on the rare occasions they met: from wiki:

"_F9F-2s, F9F-3s and F9F-5s served with distinction in the Korean War, mainly as attack aircraft, showing noticeable resistance to anti-aircraft fire; despite their relative slow speed, they also managed in downing two Yak-9s and five Mikoyan-Gurevich MiG-15s for the loss of two F9Fs. On 3 July 1950, Lieutenant, junior grade Leonard H. Plog of U.S. Navy's VF-51 flying an F9F-3 scored the first U.S. Navy air victory of the war by shooting down a Yak-9. The first MiG-15 downed was on 9 November 1950 by U.S. Navy Lieutenant Commander William (Bill) Amen of VF-111 "Sundowners" Squadron flying an *F9F-2B*. Two more were downed on 18 November 1950, and the other *two were downed* on *18 November 1952*.[4] The type was the primary Navy and USMC jet fighter and ground-attack aircraft in the Korean War._"

According to R.P. Hallion, the latter 1952 kills were achieved during a mini-epic fur ball (that may have been the basis for the dogfight described and/or depicted in the film Top Gun). They were achieved with the F9F-5 Panther variant which had been upgraded to the heavier P&W J-48 engines with an additional ~500 pounds of thrust increase over the J-42 used on the earlier panthers and an upgraded APG-30 radar-ranging gunsight.

The Panthers were flying CAP when they encountered Mig-15s, perhaps essaying a raid on the Oriskany (CV-34) although the Mig-15 reported maximum bomb load out of 200 kg would seem to make that unlikely. On the other hand, external stores might explain why the faster Migs fell prey to the slower F9F, although the dog fight as it was recounted by Hallion clearly demonstrated the Mig's performance superiority and so pilot experience may have been the arbiter of the outcome. The pilots from the O-Boat's VF-781 were reservists with probable experience in WW2.


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## GrauGeist (Jan 1, 2013)

I know that my Uncle Bill was very fond of the Panther and Banshee, he had flown both the types.


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## oldcrowcv63 (Jan 1, 2013)

GrauGeist said:


> I know that my Uncle Bill was very fond of the Panther and Banshee, he had flown both the types.



GG, I assume he was a Korean War era navy vet? When did he serve?


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## GregP (Jan 1, 2013)

I disagree with regard to swept wings. The 390 mph XP-55 Ascender was also dived and went a LOT faster than 390 mph downhill. The concept was there are would have been developed. It really doesn't matter why the wings were swept; they were swept. Let's say we disagree on this one.

I definitely agree the German data helped out a lot in the event, but be realistic. If we ever encountered a swept wing jet and made it home, don't you think the information would be relayed to the USAAF? That was one of the primary reasons for a mission debrief ... to go over the mission and to not miss anything that was new. Military secrets that surround shape are short-lived; when the shape is observed, the cat is out of the bag.


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## GrauGeist (Jan 1, 2013)

oldcrowcv63 said:


> GG, I assume he was a Korean War era navy vet? When did he serve?


He started his U.S. Navy career in WWII, served in Korea and Vietnam also. He was lost in Vietnam, 1969 



GregP said:


> I disagree with regard to swept wings. The 390 mph XP-55 Ascender was also dived and went a LOT faster than 390 mph downhill. The concept was there are would have been developed. It really doesn't matter why the wings were swept; they were swept. Let's say we disagree on this one.
> 
> I definitely agree the German data helped out a lot in the event, but be realistic. If we ever encountered a swept wing jet and made it home, don't you think the information would be relayed to the USAAF? That was one of the primary reasons for a mission debrief ... to go over the mission and to not miss anything that was new. Military secrets that surround shape are short-lived; when the shape is observed, the cat is out of the bag.


Our pilots did see a swept wing jet (on quite a few occasions) and it was reported. But it didn't influence our jet designs at the time or for a while afterwards...they had to find out _why_ the wings were swept. Seeing doesn't nessecarily mean doing...otherwise you would have seen forward swept wings on Allied planes for no aparent reason, other than the enemy was doing it...

The Ascender had "swept" wings for the sake of CoG and no other reason...yes it was reasonably fast, but I seriously doubt it's airframe would have held up if they tried to get it close to 610mph in a vertical dive. 

Note the wings of the XP-55 in relation to the engine:


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## bobbysocks (Jan 1, 2013)

i read once about the A-36 pilots would go straight down when bombing...you would think they would have hit compressibility.....but then again they had dive breaks too.


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## nuuumannn (Jan 1, 2013)

I think we are overlooking the fact that both the MiG-15 and F-86 engines were of British design and influence, not German. The Russians got a lot of mileage out of the Rolls Royce Nene. Yes, the Allies took advantage of German technology; why not? To the Victor, the Spoils. There's no doubt that had the Germans won - as extremely unlikely as that ever was - they would have also taken advantage of Allied technology. Despite their advances they never built a successful high altitude long range heavy bomber, for example - the B-29 was far in advance of any bomber the Germans had in terms of performance, range, warload, altitude all in the same airframe. Certainly the Russians took full advantage of the type. Every subsequent Tupolev design inherited genetics researched from the B-29; it was a huge influence on post-war Soviet technology, far greater than we are led to believe in the West.

Regarding German advances - I think we tend to over emphasise their importance and subsequent impact with the benefit of hindsight. At the outbreak of WW2 Germany was no more advanced than any other country. The British also had jet engines and the He 178 airframe utilised contemporary technology, the Brits _could_ have built one with ease. Circumstance was responsible for the Germans flying jets before the British, not advanced technology. As for rockets - Goddard built successful liquid fuelled rockets before Dornberger and von Braun. As for later in the war, we always tend to over emphasise the technology itself, rather than the environment in which it was born. many of these advanced projects came about because of the need for a 'wonder weapon' as a result of Germany's failure to secure victory conventionally. Many of them came about because the Germans were losing.

Lets look at the advances the Me 262 offered - yes, we recognise the swept wings and axial flow engines today, but at the time British gas turbines were far more reliable, easier to maintain and build - they were like the rotary radial of WW1 (although they were not reliable) - useful at that particular time even though there was more advanced stuff out there. Its worth remembering Britain also had axial flow engines during the war. Also, notice how neither the British nor the Americans scambled to put a jet into service to counter the Me 262 over Germany - jet vs jet combat had to wait until Korea (V 1s notwithstanding). Before anyone mentions the defficient range of early jets, the British were toying with in-flight refuelling before the war - a variant of the Meteor was later equipped for it. 

This is in contrast to the appearance of the Fw 190, which spurred the British to create a whole new mark of Spitfire that had not been planned for. As much as the German stuff gave the Allies a nasty surprise, the threat this new technology offered was containable - piston engined fighters could and did combat the 262s and defeated them, not to mention Allied air superiority over Europe and all that entailed. As for the Me 163, too little, too late. While nothing could stop V 2s once they had been launched - the answer to the threat was bomb the crap out of launch sites and production facilities - again, Allied air superiority combined with troops on the ground approaching the Reich from East and West contained the threat.

Whilst we can marvel at their use of the technology available to them, there is no doubt that for every measure the Germans took, the Allies would have created a countermeasure. That's how the war was raged and that's how it would have continued, had it done so. Luft 46? What about RAF 46, USAAF 46 and Soviet 46? Whilst the Germans might field a host of jet fighters and bomber designs, the Allies had the capacity to out build the German designs by vast amounts, even if they might not have been as exotic. Lenin once said that "quantity has a quality all of its own". The basis of the English Electric Canberra, the A.1 bomber as proposed by Teddy Petter was put to Westland, for whom he was working during the war. Wartime pressures and production would have seen Allied jets in service pretty darn quickly - and in greater numbers than what the Germans could produce.


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## oldcrowcv63 (Jan 2, 2013)

GrauGeist said:


> He started his U.S. Navy career in WWII, served in Korea and Vietnam also. He was lost in Vietnam, 1969


  May he rest in peace.


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## GrauGeist (Jan 3, 2013)

nuuumannn said:


> _I think we are overlooking the fact that both the MiG-15 and F-86 engines were of British design and influence, not German._


No one's overlooked it because no one was discussing it...it was about the _design_...you can have the most advanced engine in existance it it's worthless without a sound airframe.

The Me262 was a wakeup call, certainly, but it was the next generation of German fighters that had the Allied engineers' attention. The Ta183, P.1101 and similiar projects were under construction as WWII came to a close. This next generation (call it Luft' 46 if you like) of German fighters had advances in design over the Allied jets for several reasons and it was these advanced designs that lent themselves to the next generation of Allied jets. The Russians benefitted the most from this bounty (yes, to the victor goes the spoils) since thier jet program was much further behind than the U.S. or Britain by the close of the war.

I know it seems to be such an affront that there is the slightest, remotest possibility that there may be just a tiny shred of German influence in a postwar jet here and there, but stranger things have happened...

I mean, who would have even imagined a German rocket Scientist taking an active role in the U.S. space program...and how about that stuka pilot being an advisor to the U.S. A-10 ThunderboltII project?

Dang those pesky Germans...




oldcrowcv63 said:


> May he rest in peace.


Thank You very much!
He was never found (MIA) and he was our family's first casualty since the Civil War, even though he married into the family.


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## delcyros (Jan 3, 2013)

I personally found the memo from nuuumannn above very useful.
I know that Lockheed got a contract to buildt 5000 P-80A over the timeframe 1944 to 1947 before the order was cut down due to wars end. I am curious, does anybody happen to know the contract figures for DH Vampire and Gloster Meteor before wars end?


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## Shortround6 (Jan 3, 2013)

North American got a contract for 1000 P-80s before the wars end, it was canceled. 

I believe the the F-86 engine was NOT British inspired. The J-47 was developed from the J-35 (both General Electric). General Electric was working on the J-35 and J-33 (Whittle-based centrifugal-flow) at the same time. 

While axial engines showed the way to the _future_, in many ways they were no better than the centrifugal engines during the 40s. Narrower but heavier. Higher pressure ratios and better fuel economy were still a ways off for the most part. 

As has been said, you draw something on paper, getting it to work is another story.


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## fastmongrel (Jan 3, 2013)

Shortround6 said:


> I believe the the F-86 engine was NOT British inspired. The J-47 was developed from the J-35 (both General Electric). General Electric was working on the J-35 and J-33 (Whittle-based centrifugal-flow) at the same time.



The first production ready GE jet engine was a Whittle engine W1 built to US standards, GE centrifugal engines were branches from the Whittle tree. The axial flow engines were unique to GE and I dont believe they owed anything to German or British technology. The J35 which was the daddy of the J47 was designed before the Allies got there hands on a German jet engine. GE had been working with turbines for a long time and had priceless knowledge of working with high temperature alloys they probably could have built a working jet engine a long time before they did.


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## Rogi (Jan 3, 2013)

I think we would of seen the Horton Ho-229 had the war lasted longer and things turned out diffrently, it has a striking resemblance to some big B-2 thats flying around now a days


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## oldcrowcv63 (Jan 3, 2013)

fastmongrel said:


> The first production ready GE jet engine was a Whittle engine W1 built to US standards, GE centrifugal engines were branches from the Whittle tree. *The axial flow engines were unique to GE and I dont believe they owed anything to German or British technology.* The J35 which was the daddy of the J47 was designed before the Allies got there hands on a German jet engine. GE had been working with turbines for a long time and had priceless knowledge of working with high temperature alloys they probably could have built a working jet engine a long time before they did.



This line of discussion has been very informative to me. One question that seems to be indicated in the above statement, considering the significant sharing of technology across the pond between the allies is _whether any of the work on the Metvick F.2 might have been shared with GE_? While the F.2 took longer than Whittle's centrifugal design to mature (into the Beryl and ultimately the Sapphire), the basis for allied axial flow design work was evidently established well before Whittle's centrifugal flow design so I can imagine there may have been minimal cross-pollination. It appears to me that allied military jet engine axial flow incarnation owed essentially nothing to German technology (reiterating your point above).


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## Shortround6 (Jan 3, 2013)

GE had been building steam turbines for years and while this helps it isn't quite the benefit some think it is. Even high pressure/temp steam is nowhere near the temperature in a jet engine. Understanding flow and having the ability to machine blades and disks does help. 

Westinghouse was also working on axial jet engines as was Lockheed. 

R-R started work on the Avon in 1945 even though they didn't run one for several more years. Cutbacks in funding and the need to get the centrifugal jets working may have delayed it.


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## fastmongrel (Jan 3, 2013)

oldcrowcv63 said:


> This line of discussion has been very informative to me. One question that seems to be indicated in the above statement, considering the significant sharing of technology across the pond between the allies is _whether any of the work on the Metvick F.2 might have been shared with GE_?



I have never come across any info on technology sharing between MetroVick and GE but it is certainly possible that the engineers at both firms knew the other was working on similar lines. MetroVick was a conglomeration of several firms some of which contained a lot of US influence British Westinghouse, British Thompson Houston and Edison Swann for example so it is possible there was cross pollination so to speak. However I believe (I dont have the knowledge to be certain) that the J35 and the F2 were similar only in that they were both Axial compressor jets.


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## fastmongrel (Jan 3, 2013)

Shortround6 said:


> GE had been building steam turbines for years and while this helps it isn't quite the benefit some think it is. Even high pressure/temp steam is nowhere near the temperature in a jet engine. Understanding flow and having the ability to machine blades and disks does help.



I was thinking more of GEs work on aircraft and diesel turbosuperchargers as being of a help to designing Jets but GE certainly had all the skills and knowledge to build a working gas turbine a lot earlier than they did without any help from German or British tech.


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## delcyros (Jan 3, 2013)

Jet engines take years to be developed. One of the principal issues is that You are dependent on a high altitude pressure chamber, which not only works as a climatic controlled pressure stand with a dynamometer but also as a wind tunnel to simulate the high speed of a jet engine. Otherwise the design process is limited on empirical tests with flighttesting under conditions approaching the theoretical considerations.

Germany benefitted from two testing facilities, one in Munich and another one at Göttingen. The Herbitus facility of Munich which went into operation 1939 and was modified in 1943 for jet engines could be controlled within a range of +55 degrees C to -70 degrees C over atmosspheric conditions simulating any altitude between Sea level and 42,620ft and any speed between Mach 0.1 and Mach 0.85. It commenced testing first the BMW-003 jet engine in mid 1944. These facilities were instrumental to obtain full speed vs power altitude as well as fuel consumption charts of these jet engines and cleared the flameout and relighting behavior of these jet´s inflight. It also helped to improve combustor and injector design. 
In May 1945, american troops took possession of the facility. The facility appeared on the priority list of technology and two weeks later USAAF and USEngn. experts gathered to study the installation at Munich, which was considered to be the first known altitude jet engine testing facility. It was concluded to dismantle the facility and reconstruct in in the States. From the british side it was demanded that before dismantling, english turbojet engines were to be tested in order to resolve critical problems which appeared in service. In autumn 1945, the BMW team together with RR experts investigated the Dervent-III, Dervent-V and the Nene at the Herbitus facility.
It was shipped to the States in 1946 and is still today in operation at Air Force Arnold Engeneering Development Centre in Tullahoma / Tennessee for testing american military engines.


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## GregP (Jan 3, 2013)

GG,

The P-80 was as fast or faster than the Me 262 and generally performed quite outstandingly for a WWII jet, being about 60 mph faster than the Me 262. The F-84 just missed WWII and the design was firmly rooted in WWII. The F-84G (a developed version, certainly) was about 80 mph faster than the Me 262.

No, I think the aswept wings would have evolved when needed, and that was bout 620 mph or so. We weere knocking on the door with the P-80 and F-84, and would have pursued aerodynamic solutions. Sorry, I don't see swept wings a German-only development. I see them as a development that would be required to go faster than about 620 mph ... to beat the transonic barrier. They would have evolved, but probably a year or more later than without the German data.

Germany lacked the ability to invade the USA within a year or two after the end of WWII. so we would have had the time and the incentive for advancement of jet aircraft.

I suppose we'll just have to disagree on this one.


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## GrauGeist (Jan 3, 2013)

The P-80 was a better performer at lower altitudes than the Me262 and the 262 was better at higher altitudes... There's tons of very well researched data here in the forums that point this out...the two jets were very closely matched, and either's shortcomings were the other's advantage. So like I said, it would come down to the pilot if the two had ever squared off.


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## FLYBOYJ (Jan 3, 2013)

http://www.ww2aircraft.net/forum/aviation/p-80-v-me-262-v-gloster-meteor-21761-4.html#post775175


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## DerAdlerIstGelandet (Jan 3, 2013)

GrauGeist said:


> No one's overlooked it because no one was discussing it...it was about the _design_...you can have the most advanced engine in existance it it's worthless without a sound airframe.
> 
> The Me262 was a wakeup call, certainly, but it was the next generation of German fighters that had the Allied engineers' attention. The Ta183, P.1101 and similiar projects were under construction as WWII came to a close. This next generation (call it Luft' 46 if you like) of German fighters had advances in design over the Allied jets for several reasons and it was these advanced designs that lent themselves to the next generation of Allied jets. The Russians benefitted the most from this bounty (yes, to the victor goes the spoils) since thier jet program was much further behind than the U.S. or Britain by the close of the war.
> 
> ...



It's that whole national pride thing we were talking about in the Me262 thread...


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## nuuumannn (Jan 3, 2013)

> Dang those pesky Germans...



Indeed. Look, Graugeist, the point of my post was not to attempt to diminish Germany's technological advances, but to do the opposite and claim that, yes, the Germans had a big influence on post war Allied technology, more so in rocketry and submarine design (certainly in Russia and Britain) than jets, actually, but to counter assertions in this thread that the Allies could not have done so well without the German advances and that the Germans were somehow 'superior'. There is no doubt at all that the Allies got a fright when they saw what the Germans were up to, but by 1944 - 45, or even back to 42, that advanced technology was not what was needed for the Reich to win them the war, despite what you or many who attend this forum believe.

I bet that the average Hans or Gunther in the Wehrmacht slogging it out against the Russians in the east or the Brits and Yanks in North Africa, Italy or France couldn't care less about swept wing fighters or von Braun's rockets - if you asked him what he thought Germany needed to win the war, he would have said more PzKw IVs or machine guns, or half tracks, or even more Stukas and Fw 190s, perhaps even some long range bombers, but Ruhrstahl Kramer guided missile equipped P.1101s? I doubt it. The problem with believing too much in German advances is that there is a lot of suspension of reality required and too much hypothesis that is in defiance of what actually happened - yes, it's fun to think about the cool stuff, but history states that it made no difference at all to the outcome and it was not what Germany needed if they really wanted to win the war they started.

As for post war influence, yep, huge - virtually all British rocketry experiments in the immediate post war years were based on Helmuth Walter's engines and fuel mix. I've seen examples of British designed and built post war rocket motors with 'T-Stoff' and 'C-Stoff' painted on the fuel lines! As for jet engines versus airframes; I counter your statement by saying you might as well throw a rubber band into your advanced swept wing high speed fuselage, if you don't have a reliable jet engine in there when you are wanting to fight a war.

I would have thought that the A-10's genetics lay with the Il-2, personally, not the Stuka.


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## delcyros (Jan 3, 2013)

GregP said:


> GG,
> 
> The P-80 was as fast or faster than the Me 262 and generally performed quite outstandingly for a WWII jet, being about 60 mph faster than the Me 262. The F-84 just missed WWII and the design was firmly rooted in WWII. The F-84G (a developed version, certainly) was about 80 mph faster than the Me 262.



Do You happen to know where exactly the "beeing about 60mph faster" statement comes from? The data for mean A/C performance of both, P-80A from USAAF trials conducted 1946/7 (a sample with 38 individual datapoints) and Me-262A1 from trials conducted 1944/5 (a larger sample with 125 individual datapoints) suggest more or less comparable performance of the two types wrt their top speed. Variance is a bit larger than for piston engined A/C, and individual differences exceed the differences of the two mean performance curves, making any conclusive asessement very problematic in my point of view.
I happen to know that a P-80B was modified by clipped wing, shallow canopy and higher rated jet engine to make due with the speed record of 623mph in 1947 but this is not an operational P-80 type to be encountered anywhere except in the prototype field. It compares with a similarely modified Me-262A, the three years older Me-262V9, Werknummer 130004, modified to fit the HG-I standart in oct. 1944. The modification of a low profile canopy and new controlls and modified tail section had the intent to solve the controll freeze encountered at Mach 0.86 (in which it succeeded, albeit Baur complained about more limited visibility from the canopy) but also happened to increase the regular top speed of the A/C and pushed the top speed of the V9 with updated Jumo-004B4 (some sources say Jumo-004D) to a speed of 975km/h reported, albeit at unspecified altitude. It would be nice to verify this claim by a primary source, what I have seen on primary sources indicate a top speed of Me-262A with Jumo-004B2, specially smoothed surface and new controll surfaces to be roughly 895km/h to 900 km/h at 6000m.


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## oldcrowcv63 (Jan 3, 2013)

The impression of the high (~600 mph) speed of the P-80 may come from published performance figures for its Late 40's vintage P-80C incarnation mistakenly attributed to all models.


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## GregP (Jan 3, 2013)

Sure I know.

The Me 262 is placarded at 540 mph TAS (869 kph). The Stormbirds boys who built the new-build planes used EXACTLY the same airframe, airfoils and aerodynamic design. The only real difference was the stormbirds planes had main landing gear taken from a Grumman S2F, wood guns with weights for CG, modern engines (limited to wartime stock thrust levels ... if you fly by the POH), and updated avionics. They were so accurate, Messerschmitt issued them consecurive work numbers from the end of the Me 262 serial line!

There was a letter on the wall from Messerschmitt in Germany (on Messerschmitt letterhead) stating the wartime planes were placarded at 540 mph TAS ... any faster and you were a test pilot. So all the new-build planes are placarded at 540 mph, too, without exception. I saw four different cockpits when I was there and all had the same speed redline. I will not debate the placard limit. The limit was set by Stormbirds with consultation from Messerschmitt, and I believe them. So do the pilots of the new-build planes. They have to sign a promise to follow the limits before any of them can fly one of the birds if the insurance is to be in effect.

The Lockheed P-80 had a top speed depending on timeframe. The P-80A went 560 mph. The P-80B went across the USA over 2,500 miles non-stop at 583 mph average ... and went 600 mph at times.. ANother P-80B set a wrold speed record of 623 mph (Col. Albert Boyd). The P-80C had a top speed of 600 mph.

I simply chose the middle number, not the fastest or slowest ... and 600 mph - 540 mph (via Messerschmitt themselves remember) is a 60 mph delta. Perhaps in 1944 the difference was 20 mph, but the P-80 never suffered any lack of top speed relative to the Me 262. Of course, the me 262 had a better climb rate due to twin engines that produced a better thrust to weight ratio.

I am not one of those Americans who thinks the German hardware was no good. I LIKE the German planes and freely acknowledge their contributions that live on today. But swept wings were tried in the Soviet Union, Great Britain, the USA, Japan, France and Italy. The Germans simply had the first ones in deployed service, and they deserve the credit for that. Their captured data helped since wind tunnels that could test jets were very few at the time, and the time saved probably amounted to a year to a year and a half in 1945. So it was good to get the data, but we would have wound up in about the same place within a couple of years or so anyway. The USAF X-Plane series investigated a LOT of planforms and airfoils and configurations, and would have done so with or without German data. With it, we simply didn't have to investigate that particular data. Ditto the experimental US Navy planes, like the Douglas Skyrocket series and others.

If Germany had won, they'd certainly have wanted to look at British and Russian data since both were shooting down German planes in droves near the end of the war. Since American hardware was there, they'd have looked at ours, too, don't you think?


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## GrauGeist (Jan 4, 2013)

nuuumannn said:


> I would have thought that the A-10's genetics lay with the Il-2, personally, not the Stuka.


I'm willing to bet that Hans-Ulrich Rudel would disagree!


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## Milosh (Jan 4, 2013)

GrauGeist said:


> I'm willing to bet that Hans-Ulrich Rudel would disagree!



Can the A-10 perform near vertical dives to drop its bombs?


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## GregP (Jan 4, 2013)

The A-10 CAN perform near vertical dives to deliver ordnance but doesn't need to do so due to modern avionics that continuously compute the impact point for the selected and enabled weapons. When you have a head-up display of where the ordnance will hit if released it is much easier to take advantage of any cover, pop up, release and mask again. And it is more accurate.

With the advent of radar-aimed guns and shoulder-fired ground-to-air missiles, the dive bomber will never again be used in an active threat environment. Perhaps against people without such defenses, but you never know, do you? Best to use the strategy that offers maximum survival or simply employ smart weapons.


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## davparlr (Jan 5, 2013)

I suspect that the real influence on the A-10 was the A-1 drivers. Going back to WW2 experience is a poor representation of the modern battlefield. I think these are just interesting meetings or boondoggles just like the Northrop visit to the Smithsonian to look at the Ho/Go 229.


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## J dog (Jan 5, 2013)

davparlr said:


> I suspect that the real influence on the A-10 was the A-1 drivers. Going back to WW2 experience is a poor representation of the modern battlefield. I think these are just interesting meetings or boondoggles just like the Northrop visit to the Smithsonian to look at the Ho/Go 229.



Yes many people do agree and disagree of the influence of the A-10 and the Horton 229 the B-2. The Horton 229 I fully believe with all my heart influenced the B-2. None of these are just coincidences as people say I think personally.


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## davparlr (Jan 5, 2013)

J dog said:


> Yes many people do agree and disagree of the influence of the A-10 and the Horton 229 the B-2. The Horton 229 I fully believe with all my heart influenced the B-2. None of these are just coincidences as people say I think personally.


The B-2 design evolved from sources independent from the Ho 229 and if affected by any design it would be from the B-35/49, which it has an identical wing span. As far as the RCS and aerodynamic application, I can assure you that the group that visited the Ho 229 knew a lot more about designing a stealth aircraft than the Hortons ever did, thanks to lots of computer power and theory advancement. I suspect that there was nothing to be learned from the visit and it was just an excuse to visit a truly advanced, but premature, concept artifact of history. By the way, with the engine mounted where it was in the Ho 229, the plane would have been a flying radar reflector from the front.

I was on the initial design team for the B-2, for avionics, and was on the proposal team, so I have some, though limited in aerodynamics and RCS, insight into the technology that went into the B-2 bomber. That visit to the Ho 229 would be like the HMMWV (Humvee) designers saying "Hey, let's go to the museum and look at the Bantam Jeep!, the company will pay. We'll say it a technology study." I would have went on that trip if I could. In fact, it it had been a bomber with multiple crew, I may have been able to tag along since I was responsible for the cockpit avionics. As such, I was able to visit B-1 and B-52 cockpits for that very reason. I learned nothing about improving our designs and if anything saw things we did not want to do. I think that was the results of the Ho 229 visit also. B-1 aficionados would claim that, because we visited the B-1, it influenced the B-2, which it only did in a negative way, i.e., don't do it that way. I don't even think the Ho 229 did that.


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## davebender (Jan 5, 2013)

That's hardly surprising since the Me-262 was intended primarily to kill heavy bombers at high altitude. It's also why the Me-262 was so heavily armed.


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## davparlr (Jan 5, 2013)

delcyros said:


> Jet engines take years to be developed. One of the principal issues is that You are dependent on a high altitude pressure chamber, which not only works as a climatic controlled pressure stand with a dynamometer but also as a wind tunnel to simulate the high speed of a jet engine. Otherwise the design process is limited on empirical tests with flighttesting under conditions approaching the theoretical considerations.


The German’s may have had better facilities but it did not seem to reflect in the performance of their engines. I think the decision to focus on axial flow compressors was mistake. While the axial flow compressors certainly had the potential for better performance, as shown by the dominance of this type in present day applications, the time required to develop mature performance was considerably longer than for centrifugal compressors. Time the Germans did not have.

Without a doubt the Germans were significantly ahead of the Allies in regard to jet aircraft engine/airframe integration. The Me 262 was significantly ahead of the first efforts of the Allies. Both the P-59 and Meteor were apparently based on pre-war concepts of maneuverability over speed. Both maneuvered well but were much slower and realistically non-competitive with the German jet aircraft. Not until the P-80/Vampire development did the Allies catch up with German jet aircraft designs. In the past I have attacked Bell for basically incompetence in designing the P-59. However, later study has enlightened me to the constraints levied against Bell due to security including limited, if any wind tunnel testing or outside consulting.

However, this German advantage did not seem to apply the jet engine itself. Germans engines do not appear any more user friendly or reliable than allied engines. In addition, Thrust levels, while good to start with, soon were out distanced by Allied efforts and thrust to weight is comparatively poor. A comparison of engines operational in May, 1945, and those being developed at that time, is enlightening. 

Flyable engines

German
Jumo 004 engine
Weight - 1585 lbs
*Thrust -1980 lbs*
*Thrust to weight- 1.25*
Axial flow compressor
Usage - Me 262, Ar 234, Ju 287, Go/Ho 229

BMW 003
Weight- 1240 lbs
*Thrust- 1760 lbs*
*Thrust to weight ratio- 1.42*
Axial flow compressor
Usage- Ar 234C, He 162

Allied

Derwent I
Weight -975 lbs
*Thrust -2000 lbs*
*Thrust to weight - 2.05*
Usage Meteor 

Goblin Gn. 2
Weight- 1550 lbs
*Thrust - 3102 lbs*
*Thrust to weight - 2.00*
Centrifugal flow compressor
Usage – Vampire

GE J31-GE-5 engine
Weight 850 lbs
*Thrust 2000 lbs* 
*Thrust to weight ratio- 2.35*
Centrifugal flow compressor
Usage – P-59

GE J33-A-11
Weight- 1786 lb
*Thrust- 4000 lb*
*Thrust to weight - 2.24*
Centrifugal flow compressor
Usage – P-80

Developmental engines
German

Jumo 012
Weight - 4410 lbs
*Thrust - 6130 lbs*
*Thrust to weight - 1.39*
Axial flow compressor
Status - Seems to have not been assembled

BMW 003C
Weight- 1240 lbs
*Thrust- 1980 lbs*
*Thrust to weight ratio- 1.6*
Axial flow compressor
Usage- Ar 234C, He 162
Not completed

HeS 011
Weight- 2094lb
*Thrust -2700 lb*
*Thrust to weight - 1.29*
Axial flow compressor
Status - Prototype only

Allied
Metrovick F.2/4 Beryl
Weight- 1750 lbs
*Thrust- 3500 lbs*
*Thrust to weight - 2.0*
Axial flow compressor
Status –Ground tested Jan. ’45.

Nene
Weight - 1550 lbs
*Thrust - 5000 lb*
*Thrust to weight- 3.23*
Centrifugal flow compressor
Status - First run Oct. 1944.

Westinghouse J-30 (FH-1 Phantom)
Weight 705 lbs
*Thrust 1550 lbs*
*Thrust to weight ratio 2.2*
Status first run March ‘43
Axial flow compressor

GE/Allison J-35 (P-84 Thunderjet)
Weight 2500 lbs (estimated)
*Thrust 3750 lbs (non-afterburning)*
*Thrust to weight 1.5*
Status in development (P-84 flew Jan ’46)
Axial flow compressor

From this comparison we can see that Allied engines had better thrust to weight ratios than the contemporary German engine and therefore the German engines were much heavier. The two engines of the Me 262 was almost 1400 lbs heavier than the equally powerful single engine of the P-80, a big going-in disadvantage. The already running and ready to fly Nene engine was 2860 lbs lighter than the 20% more powerful, but not yet run Jumo 012. It was also had two and a half times the thrust of the not yet built BMW 003C but weighed only 25% more. Compared to the already running prototypes of the HeS 011, the Nene had 85% more thrust but the 011 weighed 35% more. 

While the Germans gambled on the potentially more efficient axial engines, their technology limitations and material shortages put them at an engine disadvantage in 1945 that would hamper their more advanced aircraft designs. I don’t think the axial engines caught up with the centrifugal engines until the Korean War. Even then, the Mig 15 KV-1 engine was 1312 lbs lighter than the F-86’s J-47 at the same thrust. With the more powerful engines, the centrifugal compressors could be buried in the fuselage, somewhat offsetting the advantage of the more slender axial engines.

It is also interesting to note number of different jet engines and variety of technology available to the Allies as compared to the Germans.


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## delcyros (Jan 6, 2013)

GregP,

thanks for Your memo above. You raised some interesting questions. One of them beeing that the benefit of having proper test facilities did not reflect in performance of actual jet engines. 
To answer this question, I suggest we need to settle about the qualification what is required to define "better". If the answer is thrust-weight ratio only, then I agree with Your contention that radial jet engines may offer more ease of design and production than axial jet engines in the specific 1944/45 timeframe under discussion.
However, I am not convinced that such an approach is entirely justified here. To be more precise, ease of operation is a very important criterium for early jet engines, with all the involved culprits. Neither the Dervent, Nene nor the J-31/33 had a good reliability record before fall of 1945. Problems outlined in Meteor-III and XP-80A trials record various problems, compressibility, surge, flameout under G-load and flameout at high altitude operation, rapid throttle changes and the warning not to restart the engines in flight have been mentioned as problems before beeing solved in the latter part of 1945 (in part thanks to analysis of the inflight behavior in proper BMW testfacilities at Munich).
It may also be mentioned that the standart JUMO-004B jet engine in service through 1943 and 1944 did not aim for maximum performance.
At the time of the start of the -004 development, there existed no suitable testfacility to test multistage compressors. The first two JUMO-teststands (one in Oberhausen/Bavaria and one in Dresden / Saxony) were not online before 1944. Anselm Franz, who later went to the US and there was employed as a specialist in the early jet engine program, defined the design goal of the Jumo-004 as following:
"_In consideration of the novelty of the object, in order to guarantee as much as possible the greatest chance of success, it was deliberately avoided to aim for the maximum possible._" -BMW on the other hand, did more careful layouts of the compressor and turbine, resulting in a superior, albeit delayed product, which then again, was found to be more efficient than the JUMO-004B (weight, fuel consumption, ease of operation, in buildt- overrew capability). Service lifetime of the BMW-003 was massively longer than any ww2 jet engine and larger even than many high performance piston engines of this period (200 hours as opposed to 20 to 30 usual). The over 6000 produced Jumo-004 units confirm the validity of the far sighted approach of Anselm Franz.

I must agree that centrifugal units would perhaps be a better solution than axial ones. But research in Germany was dedicated primarely to axial units. Some of the data proposed by You require correction.

The BMW-003 used by the He-162A was the BMW-003E variant and developed 930 kp (2050 lbs) max at 30 sec. overrew. The long lifetime of the BMW-003 made it the first engine to employ an overrew capability. Thus, the thrust to weight ratio was closer to 1.65 for a flyable engine in this case. 
One jet engine, which is missed in Your list is a very interesting design by Daimler Benz. The DB-007 (axial compressor, single stage axial turbine with turbine blades cooled by partial air bleed). It was the first dual flow, low bypass ration jet engine and run on the testbench in 1942. The amount of thrust developed was 2,530lbs by 1943 at very low specific fuel consumption. DB was ordered by the RLM in 1943 to discontinue the program and start a much lager design, the DB-016 (9 stages axial compressor, two stages axial turbine). The He-S011 was in the air by 1945 with various prototypes running.
Another one developmental, which missed Your attention is the BMW-018. The BMW-018 is similar in timeframe to the RR NENE and developed similar levels of thrust, albeit at higher weight. A single prototype was completed and detroyed in an air raid oct. 1944, a He-130E was reerved as a flying testbed for the engine. Östrich, who lead the BMW development program went to France and continued his work, with the different but based upon his experiences laid out ATAR-101.
Finally, the more important developmental jet engines, which at least have been testflown in ww2 were the more improved, variants of the BMW-003D and the afterburner fitted JUMO-004(-C -E). The BMW-003D had a rating of 1100kp (2424 lbs) dry. An afterburner fitted BMW-003A/-E was also under consideration (1050 kp without overrew, 1180kp with), an rocket boosted BMW-003R equipped several Me-262C pre production units. This afterburner fitted BMW-003 later was produced in the SU under the designation RD-20F along with non-afterburner fitted RD-20´s (thrust weight ratio: 1.87:1 without overrew).
The afterburner fitted JUMO-004C was only a prototype, the -E version was intended to replace the 930kp developing JUMO-004D which was in mass production at the end of ww2. The -004C developed already 1200kp on the testbench in 1944 (thrust weight ratio: 1: 1.65).
I remain sceptical that the HeS011 would soon enter mass production. It was still a developmental engine by wars end, which didn´t met all requirements. The application at wars end was the -004D with 930 kp static thrust and the BMW-003A/E with similar power at overrew.
The initial stop gap measure to improve performance was fitting of afterburner equipment to the JUMO-004, followed by a replacement with a second generation jet engine. 



> While the Germans gambled on the potentially more efficient axial engines, their technology limitations and material shortages put them at an engine disadvantage in 1945 that would hamper their more advanced aircraft designs. I don’t think the axial engines caught up with the centrifugal engines until the Korean War. Even then, the Mig 15 KV-1 engine was 1312 lbs lighter than the F-86’s J-47 at the same thrust. With the more powerful engines, the centrifugal compressors could be buried in the fuselage, somewhat offsetting the advantage of the more slender axial engines.


Possible. Though most of the challanges had been sorted out by these early axial jet engines with film cooling and hollow blade cooling technologies invented. Thus, it´s likely that more improved engines would have followed suite at a more rapid pace than in the real world post-war history. Correspondingly, the rapid achievements attained by Britain, the US and SU -in part caused by the gathering of expertise and proper testing facilities from german war bounty is less likely to occur. The relationship is dynamic, not static.


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## cimmex (Jan 6, 2013)

good info,thanks


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## J dog (Jan 6, 2013)

yes this is all very helpful and not all of this I knew. Most of it yes but some of it I had mixed up and this helped thank you.


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## delcyros (Jan 6, 2013)

GregP said:


> The Me 262 is placarded at 540 mph TAS (869 kph). The Stormbirds boys who built the new-build planes used EXACTLY the same airframe, airfoils and aerodynamic design. The only real difference was the stormbirds planes had main landing gear taken from a Grumman S2F, wood guns with weights for CG, modern engines (limited to wartime stock thrust levels ... if you fly by the POH), and updated avionics. They were so accurate, Messerschmitt issued them consecurive work numbers from the end of the Me 262 serial line!
> 
> There was a letter on the wall from Messerschmitt in Germany (on Messerschmitt letterhead) stating the wartime planes were placarded at 540 mph TAS ... any faster and you were a test pilot. So all the new-build planes are placarded at 540 mph, too, without exception. I saw four different cockpits when I was there and all had the same speed redline. I will not debate the placard limit. The limit was set by Stormbirds with consultation from Messerschmitt, and I believe them. So do the pilots of the new-build planes. They have to sign a promise to follow the limits before any of them can fly one of the birds if the insurance is to be in effect.



Ah, I understand where this idea comes from, GregP. Thanks for outlining Your reasoning. Placecarding has limited relation to top speed. What MEsserschmidt did was to issue a Mach warining in the airplane. Since it hadn´t a Mach counter the placecard was issued, referring to MACH 0.81 (at >11,000m altitude). This is limiting Mach, not maximum or crit MACH, which was MACH = 0.86 according to Prof. Messerschmidt. The Mach number was related to density of the atmossphere and at lower altitudes, the Mach number is higher indeed. 
Placecards were issued for varying reasons to all german A/C. The Bf-109 had a placecard at 650 km/h TAS, that doesn´t necessarely mean it couldn´t by design exceed 650km/h TAS. 
The top speed of the Me-262 has been extensively tested by the Luftwaffe and all serially produced planes had to undergo Luftwaffe acceptance top speed trials. Hans Fay was after the end of ww2 interviewed on performance acceptance trials and he metnions that the minimum of acceptance was 830km/h at full throttle (without specifying altitude). 
http://www.zenoswarbirdvideos.com/Images/Me262/ME262PILOTDEBRIEF.pdf
He tested ca. 50 serially produced Me-262 and only two were rejected, albeit not for lacking top speed but because of structural deficits.
For sake´s luck, I have the result of the performance trials of the average 1944/5 Me-262A with JUMO-004B from acceptance trials of a total of 125 serially produced Me-262A1 dated to february 1945, resulting in a mean of 843 km/h at a specified altitude of 800m (slightly higher than the 830km/h quoted by Fay):






Similarely, we have several performance trial data for the P-80A in the timeframe 1946 and 1947:
http://www.wwiiaircraftperformance.org/p-80/P-80A-85044.pdf
http://www.wwiiaircraftperformance.org/p-80/P-80A-85462.pdf
http://www.wwiiaircraftperformance.org/p-80/P-80-85123.pdf
http://www.wwiiaircraftperformance.org/p-80/P-80A-85075.pdf

The results of these performance trials question the validity of 560mph top speed often quoted for the P-80A. At least in the two years after end of ww2, the P-80A was unable to match this kind of performance. The graphical plot of the above performance trials is to be shown here:




Note that the fastest P-80A speed recorded is that of a december 3rd, 1946 performance trial with a specially modified P-80A with high speed nose and clipped wings, which yielded a top speed of 562 mph at 2700ft (excluded above). This is not a combat airplane -it´s a racing A/C. The fastest speed of a normal P-80A is 548 mph albeit with specially treated surface (dec. 1946). Specially smoothed paints with grey finish to attempt a smooth seal of all joints was never utilised in operational P-80A. the average speed of production P-80A is definetely lower than 560mph and compares well with the average speed from acceptance trials of the Me-262 referenced above:




I cannot see a distinct advantage for the one or other given that variances between individual trials reported for these A/C easily exceed the 10 to 15mph speed differences of the mean curves.
But keep in mind, this is late 1946 developmental state of the P-80A vs late 1944/early 1945 developmental state of the Me-262A -a developmental advantage of roughly one and a half to two years in advantage of the Lockheed P-80A. One to two years is a massive time advantage in the 1944 to 1947 timeframe and -at least in my mind- shouldn´t be left uncommented.
If You want to make a realistic asessment, You may add in proposed and already accepted improvements in the Me-262A design process, f.e. tail changes and windscreen inclination to improve crit Mach and controll issues at high Mach number as well as the fitting of JUMO-004E, both of which were to be seen already in mid 1945 produced Me-262A:



-the most notable and urgent effect was to adress the controll freeze encountered in high Mach numbers (high speed wind tunnels paid off) -Note the term "die Verbesserung der Oberflächengüte ist nur soweit berücksichtigt, wie sie für die Serie durchführbar und in Vorbereitung ist". It is important to stress that these changes were already prepared in mass production of the Me-262A jet fighter by the time this report was issued on february 23rd, 1945.



The fitting of new tail surfaces and slight improvements already gives the -262A a light advantage over the P-80A in general, which becomes very recognizable with improved JUMO-004E jet engines at all altitudes. The dry thrust of 980kp (+10% thrust over the -004B) is referred to here (Kurvenblatt 109.004-2006.14 from january 1945), not the reheat afterburner thrust of ~1200kp.




> The USAF X-Plane series investigated a LOT of planforms and airfoils and configurations, and would have done so with or without German data. With it, we simply didn't have to investigate that particular data. Ditto the experimental US Navy planes, like the Douglas Skyrocket series and others.


Agreed 100%. There is no way to support the claim that swept wing technology wouldn´t be adopted by the allies. The technology was required to engage the Mach barrier. It saved time, to get these data and proper testing procedures but principially it should have been developed at about this timeframe.


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## GregP (Jan 6, 2013)

Hi Delcyros,

Nice post, but I seriously wonder why anyone would test a P-80A in the 1946 - 1947 timeframe. By that time the P-80C was available as was the redoubtable F-86 Sabre (first flight October 1947) and the Republic F-84 Thunderjet (first flight Feb 1946). Perhaps the P-80A all they had. Were the charts with or without drop tanks? Also, I see the tests in the second link were run at 11,500 rpm instead of the 11,800 rpm maximum allowed, apparently to study the effects of the aircraft surface finish.

According to the early jets pilots we have given talks at the Planes of Fame, the Me 262 was not as fast as a P-80A. That encompasses about 30 former jet pilots of both German and American nationality, so I'll remain skeptical and simply say that during the war, they never met each other as we all know. After the war, we have testimony from quite a cross-section of test pilots that disagree with the contention that the Me 262 was faster than the P-80A. The chart with the canopy on it shows two lines and I can't tell what is what since I do't read German and even the legend is missing. The slower line maxes out at about 870 kph, which is 540 mph. 

That tells me that maybe the slower line is the service limit and the faster line is the potential, again, I can't tell. The P-80A had a similar chart with service limts and potential, too, so you should compare apples to apples and look at the max potential for the P-80 as well as for the Me 262. But by 1946/7, there were faster planes avaiable than the P-80A. Not so for the Me 262 since development ceased with the end of the war. 

I'm sure it had potential, but I'm also sure the layout with the engines out under the wings was NOT optimal for roll and that the maneuevrability of the Me 262 was not as good as for early jets with engines in the fuselage (or the Meteor), though the armament was outstanding. If development had continued, I'm sure it would have been competitive with the other early twin-jets with engines out on the wing that made it inro production, and was superior to the Meteor in speed and armament, though not in maneuverability or climb depending on conditions. 

Once the F-86 Sabre and MiG-15 were in service, the Me 262 would have been a second-line aircraft even if development had continued. That happened, coincidentally, about the end if 1947, right when your charts were apparently developed. 

The P-80 series and the Me 262 developments would have been good opponents for one another particularly if the P-80 had changed to cannon armament, and I think that if they had ever met in combat for more than a few days, it might have happened.


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## delcyros (Jan 6, 2013)

Hi GregP,

thanks again for Your memo, which helped me understanding You. You asked why anyone would test the P80A in the 1946 to 1947 timeframe. The answer is that the RAF had an instrumental interest to explore the aircraft, which had not yet passed all of it´s evolutions and trials in a testing environment which was delayed. The following data comes from MEMORANDUM OF FLIGHT TEST DIVISION and may held to answer Your questions.

REPORT SERIAL NO.TSFTE-2009, issued 29th of august 1946.
PERFORMANCE TEST OF THE LOCKHEED P-80A1 AIRPLANE, AAF No. 44-85044

I. INTRODUCTION
Flight tests were conducted on the P-80A1 Airplane, AAF No. 44-85044 at Wright Field, Dayton, Ohio between january 1946 and july 1946.  The original request for these tests was made in May 1945 on P-80A1 airplane, AAF No. 44-84995, however, this airplane was assigned to another project before accomplishing any part of the included results. (emphasize by myselfe)

Therefore, we have to conclude from the serial number that this airplane comes from the original batch of the first 345 aircraft of this contract (serials 44-84992 to 44-85336) all designated P-80A-1-LO and delivered before Sept. 1945. Note that these P-80 were propelled by a 3850 lb.s.t. rated General Electric J33-GE-11 or the similar, but Allison manufactured J33-A-9 turbojet, not by the 4000lbs version (J-33-A-17), which drove P-80-A5-LO airplanes (serials No. 44-85337 to 44-85941 and 45-8301 to 45-8262) and 218 were delivered from august 1945 to mid 1946. This latter batch had the engines cleared to brief overrew and 11,800 rpm.

I return to the report:

Tests were made in order to obtain performance at two configurations, clean, and with two 160 gal. wing tip tanks. From January 1946 through July 1946 thirty-six flights were made by Fighter operations Section Pilots with Captn. M. L. Smith flying most of the tests.

In Section II follows the summery. In the comparative tables I showed above, of course I excluded the trial data for wingtip tank records as they were not indicative for a clean P-80A1 airframe. The missed out data for them are (P-80A-1 incl. 2 x 160 gal drop tanks, all on J-33-A-9 engine unless otherwise stated):
SeaLevel: 494mph (510mph without drop tanks and J-33-GE-11 engine)
10000ft: 512mph (518mph without drop tanks and J-33-GE-11 engine)
20000ft: 513mph (520mph without drop tanks and J-33-GE-11 engine)
25000ft: 507mph (534mph without drop tanks, 519mph without drop tanks and J-33-GE-11 engine)
30000ft: 497mph (526mph without drop tanks, 515mph without drop tanks and J-33-GE-11 engine)
35000ft: 485mph (512mph without drop tanks, 507mph without drop tanks and J-33-GE-11 engine)
40000ft: 472mph

Thus a 1945 manufactured batch#1 P-80A1 in clean fighter configuration ranged in speed between 524 mph at 15050ft and roughly 534 mph at 25000ft
Interesting is perhaps section III.
III CONDITION OF THE AIRPLANE RELATIVE TO TEST.
The Airplane was flown in its normal fighter configuration, smooth paint finish[note*], an with all standart equipment in place. A photo-recorder and ballast located in the nose of the airplane substituted for the weight of ammunition for the six 0.50 caliber machine guns. The gunports were open, the gun muzzles and blast tubes were covered and taped.

The gross weights for the two configurations were as follows: clean configuration, the average starting gross weight was 11,560 lbs. which included full internal fuel of 435 gal. and 3 gal. of engine oil at a c.g. position of 31.3% M.A.C.

[note*]: Early P-80As had a overall light grey finish which was used to seal all skin joints. This finish proved to be too hard to maintain in service, and was deleted in favor of a natural metal finish. With filler and paint, these aircraft prooved to be faster than without.
and:
VIII. CONCLUSIONS.
1. The performance report is representative for production P-80A-1 airplanes. 



> According to the early jets pilots we have give talks at the Planes of Fame, the Me 262 was not as fast as a P-80A. That encompasses about 30 former jet pilots of both German and American nationality, so I'll remain skeptical and simply say that during the war, they never met each other as we all know. After the war, we have testimony from quite a cross-section of test pilots that disagree with the contention that the Me 262 was faster than the P-80A.


I fear that the number of test pilots, who have flown both, Me-262A1 and P-80A1 in fair condition is rather limited as Me-262A pilots didnt flew any P-80A1 (perhaps later derivates with waterinjection) and vice versa, only two P80A pilots flew the Me-262A as it´s known. Conventional wisdom is that the P80 Shooting Star was good for 560mph but people mean the late models not the early ones when they say this. Thus, I would expect a reception phenomen here. The fact that P80A-1 were in the latter part of 1946 refitted to P-80A-5 standart with more powerful, 4000lbs jet engines and boundary layer seperation at the air intakes adds to the confusion and the performance of the -A5 subvariant is considered to be representative for all P-80A aircraft. Pilots are interested and they do read about other planes. However, the P80A is credited with more speed in literature than it was able to attain, which is also the content of the only comparison trial between both A/C which remained long classified for this reason. I personally have never seen this report, which claims that the -262 is faster and better climbing we know some results but not the details, which would be important to know.



> The chart with the canopy on it shows two lines and I can't tell what is what since I do't read German and even the legend is missing. The slower line maxes out at about 870 kph, which is 540 mph. The P-80A had a similar chart with service limts and potential, too, so you should compare apples to apples and look at the max potential for the P-80 as well as for the Me 262. But by 1946/7, there were faster planes avaiable than the P-80A. Not so for the Me 262 since development ceased with the end of the war.


Entirely correct. The thin line is the first graph reproduced (=the mean of 121 serially produced Me-262A in performance trials) in the 2nd state of Me-262A. The 2nd state shows the potential gain of already ordered and prepared improvements in mass production (state february 1945!) with regard to more inclined front window and controll surface modifications. 
The comparison -if intended to be an apples vs apples one should compare the mean of both worlds. That is the mean of P80A1- and -5 airplanes (from 1946 trials roughly 535 mph for this airplane at optimum altitude) not with that of the Me-262A1 (from 1944 performance trials, roughly 540mph for this airplane) but with the proposed and already agreed on mass production upgrades. The 1945 manufactured P80A (from trials 1946) was not distinctly faster than the 1944 manufactured -262A (from trials 1944 to january 1945). It was slightly ahead at altitudes lower than 12000ft and slightly behind at higher altitudes. However, this P80A was still distinctly slower than the proposed serially manufactured -262A from 1945 with improvements added, which it had little opportunity to benefit from because the production ceased in april 1945.



> Once the F-86 Sabre and MiG-15 were in service, the Me 262 would have been a second-line aircraft even if development had continued. That happened, coincidentally, about the end if 1947, right when your charts were apparently developed.


I entirely agree. The limit of usefulness for the Me-262 was reached at a certain point and You correctly pointed out the engine position. It certainly would still have been useful in the night fighter role and as an experimental object to challange the MACH barrier -the V9 explored this issue wrt to controll freeze of the tail controll surfaces, another Me-262A with new and 35 deg swept back wing of HG-II standart -Werknummer 111538- was buildt but damaged in a taxiing accident without ever going airborne. The intention to explore MACH 1.0 with these airplane -along with other projects is recognizable. But as a dayfighter, it would have been replaced by more dedicated swept wing designs, such as either a swept wing He-162, the Ta-183, Hs-P135 or the Ju-EF128 at one point or another.


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## Aozora (Jan 6, 2013)

A really interesting discussion: butting in slightly regarding British research and interest in advanced concepts: I have been digging through the Flight magazine article database and have found some interesting articles on jet turbine powered flying wings (13 May 1943), and a critique of German swept wing research (17 and 24 October 1946).


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## GregP (Jan 6, 2013)

Hi Delcyros, Nice reply; I like your posts. As a former aeronautical engineering student (only made 3 years before switching to electrical engineering), I think the Me 262 did, in fact, have good development potential, but seriously doubt it would ever go supersonic. We studied that in school in 1969 and concluded it would not go supersonic ever. The report floating about claiming that one did in WWII is conjectural vapor ... take a standard Me 262 and test it in a real wind tunnel with real data acquisition. The data are fairly plain.

Nevertheless, I think the P-80 line was generally superior to the Me 262 except in armament. Just a personal opinion. We also have heard from 3 - 4 pilots who flew both the Me 262 and P-80 planes in various presentations. We have one on the first Saturday every month, always on a different plane or series of planes. The rest of the approximately 30 or so flew one or the other and reported their performance as observed, usually by reading from flying notes taken at the time by themselves. One flew the Me 262, He 280, Me 163, and He 162! He was an American of German origins who had been trapped in Germany when the war broke out, and was drafted into the Luftwaffe! His story was VERY interesting. He delivered jet aircraft from the assembly line to the front units. A truly interesting fellow! .. and with a good sense of humor.

I think that since the 1944 / 1945 P-80 and Me 262 never met in the real sky; this bantering is interesting but fairly useless; it never happened. If they HAD met, it would have been in the 1946 or 1947 timeframe since they never met in the REAL 1944 / 1945 timeframe. By that time, BOTH would doubtlessly have been faster and better developed ... but the results are pure conjecture. I have no real desire to choose one victor or the other since it never happened, but the topic IS an interesting one to me on a theoretical level.

In the real world at the Planes of Fame Museum, we find the reports from the war on both pistons and jet fighters were mostly tainted with national bias. The real planes are not really as stated in the reports, and all have their strengths and weaknesses. We really like our MiG-15 bis as well as the Sabre. All the pilots would choose the Sabre except one, who loves the MiG. Ditto the pistons. We have a LOT of experience with them at 250 - 300 mph; and some at faster speeds, usually in dives or aerobatics. Specific performance points are not always as implied by the reports of the day, and the people who flew them back then remember the characteristics as WE find them to be when flying them today. 

That probably colors my viewpoint ...


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## GrauGeist (Jan 6, 2013)

Just for the record, at speeds above Mach .86, the Me262A-1a would begin a nose-down attitude, a condition that the pilot would not be able to correct unless he was able to reduce the airspeed. After the war, the British and Russians also noted this effect when they were testing airframes for Mach capabilities.

It was certainly not capable of transonic flight.


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## GregP (Jan 7, 2013)

Great revolving pics in your sig, Garugeist! I'd like to make the acquaintance of some of the frauleins ... escepially the ones serving beer.

You know, the fabled "coffin corner," or nose-down tendency if any faster than the limiting Mach number ... I have always wondered if the nose down could have been avoided by rolling inverted and turning the nose-down into nose-up. Perhaps not ina Learjet, but maybe in an actual fighter.

The early Lears had a real bad coffin corner ... 2 - 3 faster and you were into Mach Tuck (the "nose-down" pitching moment) and 2 - 3 knots slower and you would stall; speed control was vital, to say the least. The newer Lears have 20 - 35 knots of cushion at max altitude, so they're pussycats by comparison.


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## GrauGeist (Jan 7, 2013)

Well Greg, it seems like inverting would be a solution for that condition, but if you're in that zone, chances are your control surfaces are going to be sluggish or non-responsive. You may be able to "break" it by pushing foreward on the stick but I would think that one would have a better chance by bringing the engines to an idle and trying to bleed off speed until controls are responding again (this is of course if you have the time altitude, otherwise Jesus better be your friend).


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## michaelj_warbird (Jan 8, 2013)

J dog said:


> Ok Let's say the Germans won WW2 and the Korean war still happened no matter any world changes after that. Would the German experimental planes or fastest planes be capable of taking on MiG -15s or Sabres? This is not me saying that the Germans could win the war though this is just me asking a question. Please comment and please make things appropriate and respectful towards others opinions!


 
great question.

I'm new to this web site by the way. It's nice to be here, among fellow aviation enthusiasts !

hmm, it depends on what the germans would have done. Would they have been satisfied to have taken all of europe and russia? I think so, probably. If they would have really won,, well they did have plans to attack the usa, so they might have done that, and , they were allied with japan, so maybe they would have formed a world alliance with japan and formed a kind of super country with japan. but knowing germans, they would want it to be a german super country/continent and not totally be combined with japan.

any way, hmm, well if they would have really defeated russia, which they were engaged with, then they would have had to really beat russia, meaning that russia would not have even existing as russia any more, and never would have made korean war-era migs. But instead russia would have fallen under the third reich's command, and it would be a part of the third reich. so the real question is: would the cold war have been between russia and usa, as it was. and the answer is no, because russia would be part of the third reich, and usa possibly also.

so thats a complicated question, (it's a what if question) but anyway , many countries drew upon what was done with the me-262 and other advanced designs that the germans developed, and integrated it into their own, for the next generation craft.

hmm , another point would be, what if the germans had not made such advanced craft during ww2. then what would the korean war have looked like. and we know the answer to that. probably there would be more piston engined planes, and some less advanced jets , and everything would have slowed down, into the 70's and 80's etc, so we would not have had as advanced jets today as a result. course we probably would not have gone into space at all.


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## Njaco (Jan 8, 2013)

I have to hand it to you guys for having an informational and respectful conversation without any [email protected] Love it.

The earlier post by Davlpar about the differences of a axial and centrifugal engine (and the relation to the Me 262) is spot on to just about everything I've seen or read about jet engines. The follow-up information by everyone else is making this a really great thread to read through.


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## davparlr (Jan 8, 2013)

delcyros said:


> GregP,
> 
> thanks for Your memo above. You raised some interesting questions.


 It’s okay to address your response to Greg instead of me when replying to my post when it’s negative, just get my name right when it positive! 


> I suggest we need to settle about the qualification what is required to define "better". If the answer is thrust-weight ratio only, then I agree with Your contention that radial jet engines may offer more ease of design and production than axial jet engines in the specific 1944/45 timeframe under discussion.


Thrust-to-weight or power-to-weight has always been a critical parameter for aircraft engines. I don’t think you can deny that the 1400 lb difference between the Me 262 and the P-80 would not make a significant impact to performance to either plane.



> However, I am not convinced that such an approach is entirely justified here. To be more precise, ease of operation is a very important criterium for early jet engines, with all the involved culprits. Neither the Dervent, Nene nor the J-31/33 had a good reliability record before fall of 1945.


I don’t think any jet engines had good reliability during this period. I don’t think the German engines had any special claim to reliability (MTBF), engine replacement availability, operator friendliness, or any other criteria related to overall jet operations.


> Problems outlined in Meteor-III and XP-80A trials record various problems, compressibility, surge, flameout under G-load and flameout at high altitude operation, rapid throttle changes and the warning not to restart the engines in flight have been mentioned as problems before beeing solved in the latter part of 1945 (in part thanks to analysis of the inflight behavior in proper BMW testfacilities at Munich).


Like I said, I think the German engines had their share of problems like difficulty to start, flame-outs with rapid throttle movement, etc. By the way, how did they test for flameouts under G-load? Did they have a wind tunnel mounted on a centrifuge contained in a pressure chamber? Now that would be something to see.



> It may also be mentioned that the standart JUMO-004B jet engine in service through 1943 and 1944 did not aim for maximum performance.


I suspect all the engines mentioned went through the same process of conservative design. They were not fools. Only the acceptable risk was a variable and we do not know what that is on most of the engines.


> Some of the data proposed by You require correction.


This doesn’t surprise me since I don’t have a lot of resources in engine development.



> The BMW-003 used by the He-162A was the BMW-003E variant and developed 930 kp (2050 lbs) max at 30 sec. overrew. The long lifetime of the BMW-003 made it the first engine to employ an overrew capability. Thus, the thrust to weight ratio was closer to 1.65 for a flyable engine in this case.


The only references I have shows 1760 lbs, but I can’t say they are unimpeachable.



> One jet engine, which is missed in Your list is a very interesting design by Daimler Benz. The DB-007 (axial compressor, single stage axial turbine with turbine blades cooled by partial air bleed). It was the first dual flow, low bypass ration jet engine and run on the testbench in 1942. The amount of thrust developed was 2,530lbs by 1943 at very low specific fuel consumption. DB was ordered by the RLM in 1943 to discontinue the program and start a much lager design, the DB-016 (9 stages axial compressor, two stages axial turbine).


Apparently the 007 did not exist in 1945. I have no information on the 016.


> The He-S011 was in the air by 1945 with various prototypes running.


I think the aircraft applications of the HeS 0011 was flying test bed flights which means that they were more advanced than ground test but not yet fully qualified for military application.



> Another one developmental, which missed Your attention is the BMW-018. The BMW-018 is similar in timeframe to the RR NENE and developed similar levels of thrust, albeit at higher weight. A single prototype was completed and detroyed in an air raid oct. 1944, a He-130E was reerved as a flying testbed for the engine. Östrich, who lead the BMW development program went to France and continued his work, with the different but based upon his experiences laid out ATAR-101.


I think the program was a mess in 1945, if it existed at all. However, the BMW work certainly turned into a modern turbojet engine in France, one of my criteria for the evaluating the viability of war designs. Still, I doubt the engine met the contemporary allied designs in thrust and thrust-to-weight.



> Finally, the more important developmental jet engines, which at least have been testflown in ww2 were the more improved, variants of the BMW-003D and the afterburner fitted JUMO-004(-C -E). The BMW-003D had a rating of 1100kp (2424 lbs) dry. An afterburner fitted BMW-003A/-E was also under consideration (1050 kp without overrew, 1180kp with), an rocket boosted BMW-003R equipped several Me-262C pre production units. This afterburner fitted BMW-003 later was produced in the SU under the designation RD-20F along with non-afterburner fitted RD-20´s (thrust weight ratio: 1.87:1 without overrew).
> The afterburner fitted JUMO-004C was only a prototype, the -E version was intended to replace the 930kp developing JUMO-004D which was in mass production at the end of ww2. The -004C developed already 1200kp on the testbench in 1944 (thrust weight ratio: 1: 1.65).
> I remain sceptical that the HeS011 would soon enter mass production. It was still a developmental engine by wars end, which didn´t met all requirements. The application at wars end was the -004D with 930 kp static thrust and the BMW-003A/E with similar power at overrew.
> The initial stop gap measure to improve performance was fitting of afterburner equipment to the JUMO-004, followed by a replacement with a second generation jet engine.


All of these advances were pushing performance up on the axial flow engine but were still behind the performance of the J-33 in the P-80 and well below the British Nene engine, T/W ratio of 3.23. I ignored afterburning performance as I consider it a trivial engineering effort compared to the core jet engine design and was relatively easy to implement. Even the very early L-1000 jet engine by Lockheed discussed thrust augmentation by injecting fuel into the turbine blades. Also, the Nene offsprings in the P-80 and Mig-15 added afterburners to make the F-94 and Mig-17 (which was formidable even in the Vietnam War). In addition, the early jets were notoriously big consumers of fuel and afterburners are voracious, there use would significantly impact any airborne operations.



> Possible. Though most of the challanges had been sorted out by these early axial jet engines with film cooling and hollow blade cooling technologies invented. Thus, it´s likely that more improved engines would have followed suite at a more rapid pace than in the real world post-war history. Correspondingly, the rapid achievements attained by Britain, the US and SU -in part caused by the gathering of expertise and proper testing facilities from german war bounty is less likely to occur. The relationship is dynamic, not static.


The end of the war certainly dried up military spending in the West slowing down any development. Had the war continued competitively, it is likely that the aviation development available in 1949-50 would be available in 1946-47 and it would have continued to see-saw in technology as it had been doing, excluding any nuclear events. Due to vast resources the Allies were quite capable of reacting quickly, usually within months of the introduction of new technology. And they already had advance engine development in the Nene and J-33, several programs going in axial engines some of which will evolve into great engines, theoretical knowledge on swept wing designs. The Germans certainly had a significant advantage in aerodynamic theory, jet aircraft integration capability (mostly eliminated with the advent of the P-80/Vampire) and test facilities, as you have pointed out, but, in general, like I said the Allies had a huge capability to respond.


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## Jack_Hill (Jan 8, 2013)

@Davparlr
Hi,
"I don’t think the
German engines had
any special claim to
reliability (MTBF),
engine replacement
availability, operator
friendliness, or any
other criteria related to
overall jet operations."
As far as Me-262 and He-162 are concerned, I don't think it's true.
Quick field engines replacements where possible and operator friendly, because designs planned it from the very start of the projects.
Brand new engines were massively available(brand new a/c too).
From the fall of '44 until capitulation, Germany was kind of "open bar" for parts and a/c.
Corruption and disorganisation were the rules.
Nice thread, educative, love it.


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## DerAdlerIstGelandet (Jan 8, 2013)

michaelj_warbird said:


> If they would have really won,, well they did have plans to attack the usa, so they might have done that



Germany did not have a desire to invade the USA. Nor did they have plans to do so. What plans do you speak of?


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## GrauGeist (Jan 9, 2013)

The German leadership considered and evaluated bombing the U.S. mainland to demoralize the citizens in the hopes that it would pull the U.S. out of the war.


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## DerAdlerIstGelandet (Jan 9, 2013)

GrauGeist said:


> The German leadership considered and evaluated bombing the U.S. mainland to demoralize the citizens in the hopes that it would pull the U.S. out of the war.



Yes, I know that. I have a great book on the subject. There however where no plans to actually bomb the US drawn up. Nor was there a desire or plan to "invade". Even Hitler knew that if sn invasion of England was impossible, the US was out of question. I highly doubt Hitler even would have wanted that. His plans were always to the east.


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## oldcrowcv63 (Jan 10, 2013)

DerAdlerIstGelandet said:


> Yes, I know that. I have a great book on the subject. There however where no plans to actually bomb the US drawn up. Nor was there a desire or plan to "invade". Even Hitler knew that if sn invasion of England was impossible, the US was out of question. I highly doubt Hitler even would have wanted that. *His plans were always to the east.*



But only after he had bopped the French a good one for all their past invasions and pillage of the Deutsches Vaterland in past centuries. 

On my trip to Germany in 2010, I kept seeing the ruins of castles along the Rhine and Mosel and whenever asking our Dutch-Belgium tour guide what happened, her response was inevitably: Sacked and burned by the French sometime in the last 400 years.


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## The Basket (Jan 10, 2013)

If Goddard and Whittle had been funded to the max then the rocket and the jet would have come out much sooner.

The V2 was a big Goddard rocket and when the Germans were asked by the Americans for tech details, they were surprised as they got the details from American research. 

The Lockheed L-133 with the L-1000 engine proves that forward thinking was there.


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## delcyros (Jan 12, 2013)

I apologize, Dave, if I replied in a wrong way.

You have pointed out Your thoughts in various aspects.Let me add my responses.



> Thrust-to-weight or power-to-weight has always been a critical parameter for aircraft engines. I don’t think you can deny that the 1400 lb difference between the Me 262 and the P-80 would not make a significant impact to performance to either plane.



As far as thust-to-weight ratio goes, I already pointed out that Schelp choosed a less optimal solution over a more advanced to assure it´s functionality and mass production. Germany aleady had a 1:2.2 ratio engine running in 1942, the axial HeS030, developing 1895lbs of thrust while weighting only 860lbs (benchtested feb 1942, flighttested Nov 1942). So appearently, thrust-to-weight ratio were not critically important paramters in selection of further development -at least in this period.
As far as Me-262 and P-80 goes, the difference in weight of the -262´s engines are offsetted by better integration and high speed optimization of the airplane. Performance is not different between both. Speed is roughly identic and the thrust-to-weight ratio is actually slightly favours the -262A (0.28 vs 0.26 at max. gross weight). I can see advantages for the P-80 in roll and service ceiling, though not at limiting Mach number, which represents in my opinion a more critical design parameter for a first generation jet (0.80 as opposed to 0.84).




> I don’t think any jet engines had good reliability during this period. I don’t think the German engines had any special claim to reliability (MTBF), engine replacement availability, operator friendliness, or any other criteria related to overall jet operations.


I disagree with regard to the generalization of the statement. If You rely it to Jumo-004B engines, I could agree. But already with -004A engines it´s difficult to follw and BMW-003 engines were significantly ahead in terms of servicability times, reliability, flameout resistence in acceleration and operator friendliness.



> I think the German engines had their share of problems like difficulty to start, flame-outs with rapid throttle movement, etc.


Again, You are generalizing a problem related to Jumo-004B engines and project the issue on other designs. I have a He-162 operators manual right in front of me. I quote from the section of emergancy operation (p.22):


> B. Durchstarten.
> 1. Schubdüsenschalter muß auf "S" stehen
> 2. *Zügig Vollgas geben*
> 3. Fahrwerk kann eingefahren bleiben
> 4. Wieder normal anfliegen und zur Landung ansetzen



That´s quite different to the careful operation of the -004B, whiches RPM shouldn´t drop below 7000 otherwise extreme care has to be applied to prevent turbine blade burnout. The difference was in design.



> The only references I have shows 1760 lbs, but I can’t say they are unimpeachable(...)
> Apparently the 007 did not exist in 1945. I have no information on the 016.


Originally, the He-162A was intended for BMW-003A engines (Baubeschreibung from oct. 1944) but all serial planes were fitted with BMW-003E-2 (pilots operators manual, p.3). Thrust rating 1760lbs is 9500rpm, overrew is 9800rpm. See the soviet trials on two of the He-162, they received.
Daimler Benz DB007 Jet engine (Image Ref: A07054H) | Flickr - Photo Sharing!
The dual flow, DB-007 was running 1943 and later was abandoned by Schelp and DB engaged work on the DB-017. Anthony Kay has more details on this jet engine in his book.




> I think the program was a mess in 1945, if it existed at all. However, the BMW work certainly turned into a modern turbojet engine in France, one of my criteria for the evaluating the viability of war designs.


Thanks that You referred to this issue. Are You aware that BMW-technicians under Karl Prastl rebuildt the BMW-018 in 1945 (OKB-I) on order of the soviet occupational forces in Eastern Germany? The designers first were tasked with BMW-003C/D and then had to basically "recreate" the BMW-018 with not all documentation surviving the war and all toolings destroyed. They benchtested the engine in oct. 1946 in Spandau/ near Berlin, roughly two years after the first prototype was destroyed in an air raid. Altough the engine was not put into production, it offered the soviets valuabel insights in high performance axial jet engine design.
I do not disagree that radial jet engines had a thrust-to-weight advantage in the period under discussion. The RR-Nene and Dervent-V were perhaps the best-overall-engines to see service in the mid/late 45´s, all factors considered.
But does this hands any advantage to the allies wrt a jet case? I don´t think so. The advantage was mostly wasted by suboptimal aircraft design and lack of knowledge in the transsonic realm. It was not until the late 40´s that the allies had something which could beat the then contemporary version of the Me-262. And it´s highly unlikely, that the this airplane, the swept wing P-86 would have been produced given the fact that the straight wing version XP-86 didn´t offered better performance than the rather ill fated P-84.





This graph shows the limiting Mach number of known airplane designs of the allies and Germany. It´s appearent that it took until the advent of the swept winged XP-86 to beat clearly the Me-262A.
There is probably some convergence in the late 47´s but not before. Note that I excluded german paper projects and only used fightr airplanes, which at least had their first flight under own power in the time before VE-day (Germany) and before 1948 (others).

[IMG=http://img341.imageshack.us/img341/141/limmach.jpg][/IMG]

This graph shows the development of thrust-to-weight ratio at max. gross weight for these airplanes. The USAAF does defenitely not benefit at all from their engines with better thrust-to-weight ratio. The RAF does, however, with the Dervent-V driven Meteor Mk. IV kicking ass.





The final graphs shows speed at best altitude vs prototype date (The swept wing XP-86 beeing excluded but the straight wing XP-86 is within).


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## davparlr (Jan 15, 2013)

delcyros said:


> > As far as thust-to-weight ratio goes, I already pointed out that Schelp choosed a less optimal solution over a more advanced to assure it´s functionality and mass production. Germany aleady had a 1:2.2 ratio engine running in 1942, the axial HeS030, developing 1895lbs of thrust while weighting only 860lbs (benchtested feb 1942, flighttested Nov 1942). So appearently, thrust-to-weight ratio were not critically important paramters in selection of further development -at least in this period.
> 
> 
> It seems that Germany made two mistakes in jet engine development (the allies made a few mistakes themselves) the first being to ignore the simpler and less exotic metal intensive centrifugal compressor engine, and two, cancelled the more efficient and lighter HeS 30 engine. It is interesting to note that the HeS 30 had a similar development and performance as the Westinghouse J-30 engine which first ran March, 1943 (the first run of the HeS 30 resulted in a redesign and did not run to full rpm until Oct., 1942). The axial flow J-30 engine ran the first time surprising the engineers. At that time there was little funding and the engine did not start flying test bed activity until Jan, ’44. The engine developed 1500 lbs of thrust with a 2.2 thrust to weight ratio.
> ...


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## davparlr (Jan 15, 2013)

Continued.



> The dual flow, DB-007 was running 1943 and later was abandoned by Schelp and DB engaged work on the DB-017.


My comment on the 007 not existing in relation to 1945 was because it was cancelled. I didn’t mean to imply it never existed.


> Anthony Kay has more details on this jet engine in his book.


I ordered this right before I read your recommendation. Thanks for the recommendation; it tells me I didn’t waste my money.


> The RR-Nene and Dervent-V were perhaps the best-overall-engines to see service in the mid/late 45´s, all factors considered.


I would agree.



> But does this hands any advantage to the allies wrt a jet case? I don´t think so. The advantage was mostly wasted by suboptimal aircraft design and lack of knowledge in the transsonic realm.


I agree with this except that I don’t think transonic knowledge came into play with the Me-262, just sound engineering and excellent aerodynamic design work.


> It was not until the late 40´s that the allies had something which could beat the then contemporary version of the Me-262.


I think that by late ‘45 early ’46 both the P-80 and Vampire would be operationally equivalent to the Me-262. The Meteor would be a bit later.


> And it´s highly unlikely, that the this airplane, the swept wing P-86 would have been produced given the fact that the straight wing version XP-86 didn´t offered better performance than the rather ill fated P-84.


I think that, had the war continued, it definitely would have. Remember America built the P-40 up till 1944. It would have continued to develop different sources of fighters. 
I would not consider the P-84 as being “ill fated”. It certainly had its problems but so did other jet aircraft. It took the Me 262 three years from first flight to being full operational, the same time it took the F-84, 1946 to 1949 when the D became operational. Aerodynamically it was impressive, reaching 611 mph on 3750 lbs thrust, less than the Me 262 and P-80A. The YF-84F was faster than the F-86E with the same engine thrust. For what it is worth, the USAF claimed the F-84 destroyed 60% of all ground targets in Korea.



> This graph shows the limiting Mach number of known airplane designs of the allies and Germany. It´s appearent that it took until the advent of the swept winged XP-86 to beat clearly the Me-262A.


You are correct in limiting Mach number but this is a minor player in the balance of fighters. If it played a big part, the Spitfire would have been unbeatable. The Me 262 did not have the performance advantage in speed, climb, or ceiling to clearly beat the P-80 during this period so this argument is moot. I have already discussed the advantages/disadvantages of dive speed to ceiling in my F-86 vs. Mig-15 comments. By the way, since the P-80 was cleaner, it probably had a better initial dive speed advantage although the Me 262 would eventually catch up.





> This graph shows the development of thrust-to-weight ratio at max. gross weight for these airplanes. The USAAF does defenitely not benefit at all from their engines with better thrust-to-weight ratio. The RAF does, however, with the Dervent-V driven Meteor Mk. IV kicking ass.


I seem to be missing a graph here. I don’t see anything showing thrust to weight. Again, max gross weight is not a good reference in that it punishes designs for load carrying ability. Ideally it is best to start with empty weight and add equal loads like pilot and equivalent fuel and armament. However, this data is often hard to get, but operation gross weight can be used. The data I have shows operational gross weight of the Me 262 as being 13,250 lbs, the P-80 operational gross weight of 11,700. However, the P-80 carries about 250 gallons less fuel which would make, if corrected, the operational weight of both aircraft the roughly same (however it is interesting to note that the range of the P-80 on full internal fuel is about the same as the Me 262 on full fuel even though the P-80 fuel load is quite a bit less). Thrust to weight is about the same except maybe better for the P-80 if equivalent fuel to performance weight is considered.
The empty weight of the Me 282 is listed at 9742 lbs and the P-80A at 7920 lbs. Loaded weight is similar at same fuel load, so your comment seems confusingly true. Without a detailed break out of weight, I have no explanation. 



> The final graphs shows speed at best altitude vs prototype date (The swept wing XP-86 beeing excluded but the straight wing XP-86 is within).


This chart seems wrong in that it shows year to speed, not year to altitude. 

The question I have is – if Germany had started pouring money into a centrifugal compressor jet engine at the start, could they have had a reliable, manufacturable 4-5000lb thrust jet engine, like a Nene, in 1943, and, with Germans advanced aerodynamics and research could they have fielded a jet in quantity in late ’43 early ’44 with performance of the Me 262? If so, how would this affect the war? This would be a good topic for another thread.


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## awack34 (Jan 15, 2013)

The average production p80a (which were unpainted) had a top speed of 525 mph and a cruise of 422mph, if painted they could acheive about 535/537mph....but they quickly discontinued it because the paint would chip which would effect the aircrafts performance even more, so wasnt suitable for production aircraft.


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## delcyros (Jan 16, 2013)

Dave,

Let me first express that my perception of Your posts is a reasonable collection of arguments. Thanks for all the effort You made with that. I appreciate that.

You asked a couple of interesting questions. One of them was, whether or not radial jet engines may have allowed the Luftwaffe to field a proper jet fighter in the 43 to 44 timeframe. 
My reading of the topic indicates, though not necessarely exhoustive, that radial jet engines of the period had certain favourable design elements. You have already mentioned a better thrust-to-weight ratio and who could disagree with that in light of the Nene and Dervent-V?
However, the design environment of the GAF called distinctly for airframes, whiches details of jet engine installation required external mounts to ease maintenance and allow for rapid replacement of worn out engines (see f.e. underwing mounts in He-280, Me-262, Ar-234 and He-162, the principal jet engined designs adopted for development in the early and mid war period. Only with the 1944 and later designed jet A/C little by little fuselage mounts became acceptable from a design point of view. We have to reckon with difficult working conditions and fear of technological failure in this period. Leaking engines were quite common but in a fuselage mounted one this would determine the eventual loss of the airplane. Only when safety record became advantageous this requirement was finally dropped (Ho-229, Me-P1101, Ta-183 and -Flitzer, Ju-EF128, Hs-P135 and others). It was the ultimate reason for both Heinkel and Messerschmidt beeing forced to avoid fuselage mounts for their He-280 and Me-262, respectively.
However, with radial engines in external mounts, frontal diameter of the jet engines very soon becomes a critical design parameter. Thus, I remain convinced that the GAF got the compromise they desired most with axial jet engines in external engine nacelles. This system would not have worked out well with radial engines of bigger frontal diameters (f.e. HeS003 and HeS008). Also, one has to give RR and the UK (or US- for that matter..) engeneerers credit for developing ingenious solutions for the issues they engaged in developing a high thrust radial jet engine. I cannot see this happening in Germany, radial engines always developed less thrust than axial ones.
However, that Schelp canceled the HeS030 was a clear mistake, agreed.



> I have read that CD0 for the P-80 is quite a bit less than the Me 262 indicating the aircraft design is cleaner which makes sense with the embedded engine. Some comment was made as to inefficiencies of the inlets that reduced thrust and slowed the aircraft down to the Me 262 levels. This also makes sense since inlet and duct design is a sophisticated effort which would have been in its infancy in the 1940s. Still, the P-80 did reflect a more advanced and flexible design. The only real advantage the Me-262 had was the accidental help of slightly swept wing which was the result of fixing a design fault.


I agree with this observation. The YP-80A makes at comparable or less netto thrust more speed at Sea Level, implying a lower CD0 for the airframe. There are losses for duct and intake , though this will remain difficult to quantify (f.e. Messerschmidt made tests using a -262A with various 8 to 11ft long intake pipes and measured a loss of min 6% thrust). This changes with altitude as Mach compression raised drag becomes more and more an issue. This is why the -262A -in average- is slightly faster at higher altitudes (12000ft and more). However, I consider the -262A aerodynamically more advanced. Because of the adoption of a Wing sweep in combination with thin airfoils, leading edge slats (to counter adverse low speed handling inherent to all swept wings) and partially movable elevator rather than trim tabs. Even if accidently, these elements were forward directed. Wing root mounts for the engines were considered, too, in combination with larger wingsweep and more powerful engines (HG-III), which eventually would make the plane capable for true transsonic operation, something the P-80 never was capable of.



> The P-80 has over a mile higher ceiling, which would give it a significant energy advantage.


I will concede this point. But how much fight took place at over 40000ft altitude in ww2?



> Money could not buy, for example, the special metals required for the heat-resistant parts. The British started investing large amounts of money in Whittle’s project only in 1940. It helped them close the gap with the Germans only because their engine was less complicated. As a result, at the end of WWII British jet engines were less modern, but more reliable, while German engines were more advanced, but less reliable.


This is that sort of generalizations which I invested some efforts to avoid. What he is speaking about is basically the Jumo-004B state as of mid to late 1944. With adoption of film cooling, hollow blade cooling, and Tinidur heat resistent alloys, these problems were largely overcome, though others (harmonic vibrations) appeared instead. The BMW-003 was much better in reliability than the Jumo-004 (by ten times wrt average service lifetime!) but this details is completely missed by the author. BMW went so far to employ acoustians to study harmonic vibrations for the turbine blades with the result that the service lifetime was substantially increased. When the russians copied the BMW-003, they replaced Tinidur with domestic El steels, which cut the service lifetime of the jet engine down to 100 hours. Still sufficient for their purposes and favourable with other axial jet engines. The BMW-003 also had no issues with flameout caused by rapid throttle changes due to the accelerator valve which was missing in the Jumo. 


> I think that by late ‘45 early ’46 both the P-80 and Vampire would be operationally equivalent to the Me-262.


I guess so. But do not forget that the 1944 Me-262A is quite a bit different than a late 45 or early 46 one. The improvements mentioned earlier in this thread would represent a serious enhancement of capabilities of the jet A/C and I see no reason why they shouldn´t be applied in an apple vs apple comparison.



> I would not consider the P-84 as being “ill fated”. It certainly had its problems but so did other jet aircraft. It took the Me 262 three years from first flight to being full operational, the same time it took the F-84, 1946 to 1949 when the D became operational. Aerodynamically it was impressive, reaching 611 mph on 3750 lbs thrust, less than the Me 262 and P-80A.


The P84 had a significantly lower crit Mach due to it´s thick airfoil sections. Thus, any performance advantage would materialize only at Sea level altitudes where the distance to limiting Mach numbers is large. Low altitude would be avoided in air combat due to fuel consumption issues, range at high altitude in the P-80 and P84 was twice to three times higher than at Sea level. At high altitude, the 1948 P-84 with 5400lbs jet engine is not much faster than the 1944 state standart -262A and slightly slower than the [late -45] -262A with 10% uprated engines and minor aerodynamic improvements approved for mass production in feb. 45.



> If it played a big part, the Spitfire would have been unbeatable. The Me 262 did not have the performance advantage in speed, climb, or ceiling to clearly beat the P-80 during this period so this argument is moot. I have already discussed the advantages/disadvantages of dive speed to ceiling in my F-86 vs. Mig-15 comments. By the way, since the P-80 was cleaner, it probably had a better initial dive speed advantage although the Me 262 would eventually catch up.


My perception differs here considerably. The comparison between Spitfire and jets is not entirely correct here. One of the reason lies in the fact that the difference between operating cruise speed in limiting Mach is much narrower for a jet than for a prop driven plane operating at any altitude.
This distance defines the tactical ellbow room. At high altitude, where M=1.0 is around 660mph the P80 engages it´s limiting Mach number already at 528mph. That´s just 40 to 50 mph more than the P80´s 96% cruise speed. Thus, the P80 can gain only 40 to 50mph speed before becoming increasingly difficult to controll, hardly sufficient to gain any tactical advantage. The Spitfire can gain 150 to 200 mph before encountering similar problems. A more menaingful comparison would stress the problem of low limiting Mach number of the P-38 (M=0.68 IIRC), which experienced dive issues due to operating closer to it´s limiting Mach number.


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## tomo pauk (Jan 16, 2013)

Just wanted to say a big thanks for the members contributing stuff for all interested to read learn. And with a great attitude to boot.


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## GregP (Jan 17, 2013)

Delcyros, where does your graph for limiting Mach numbers come from? I see no report number ... just a graph. Is it from a flight simulator or a real report? If so, by whom?

Not saying it is wrong, just wondering.


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## Tante Ju (Jan 17, 2013)

davparlr said:


> While the Germans gambled on the potentially more efficient axial engines, their technology limitations and material shortages put them at an engine disadvantage in 1945 that would hamper their more advanced aircraft designs. I don’t think the axial engines caught up with the centrifugal engines until the Korean War. Even then, the Mig 15 KV-1 engine was 1312 lbs lighter than the F-86’s J-47 at the same thrust. With the more powerful engines, the centrifugal compressors could be buried in the fuselage, somewhat offsetting the advantage of the more slender axial engines.



The only reason axials had to catch up with centrifugals was that Allied axial development was in its infancy and would need years to produce a practical engine in 1945 and the Germans who had progressed the technology stopped their own development. But technology needed time and neither the Allies could skip early development setbacks, the ones the Germans fixed gradually since 1939 to produce a reasonably operational axial jet, the Jumo 004, which was as conservative as possible to speed up development. The Allies could not do the same sooner. But even the British dumped it and used instead the axial Avon, but that had to wait until 1950 because RR started the Avon's development only in 1946. And until then, they used whatever they had: centrifugals. It was hardly a choice on their part, their own axial developments were simply immature and or not very successfull (like the Metrovick).

The Derwent was already much (+20%) larger diameter (and thus drag) than German axials, which is why the Meteor was so much slower. The GE J33 or the Nene was again much larger (+20%), essentially reached the size of the larger radial piston jobs, so it had to be put into the fuselage as it already grown out the wings. The next step would be an even larger engine and the fuselage starts to grow fatter, drag rises steeply and you are entering the area rapidly decreasing dividients and this point was already met in 1945. To achieve maximum speed a minimum fuselage cross section (~drag) is required. Look at the Nene's history, a great centrifugal engine no doubt, but essentially it stuck right where it started, even the version in the MiG 15 did not improve much on its thrust. 

See the pattern here? Centrifugal jet engines were dead end and extremely limited development potentional for fighter applications, basically the way they increased output meaningfully was increasing the size (diameter) of the engine. Axial engines OTOH could theoretically grow in length almost infinitely while maintaining the same diameter OR increasing it.

Thrust to weight ratio is interesting and a good T/W is useful for improving climb, but does next to nothing to improve top speed, especially at jet top speeds, which was what jets were all about. Even T/W ratio had less importance with jets than with prop jobs since the jets made their best climb at about twice the speed than prop jobs where induced drag is far less dominant.



> It is also interesting to note number of different jet engines and variety of technology available to the Allies as compared to the Germans.



How so? 

The GE J31 was essentially the American license of the Whittle W.1, the GE J33 was essentially the same engine, enlarged.
The case with the Derwent and Nene is again the same, the Nene was essentially the same engine, enlarged.


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## delcyros (Jan 17, 2013)

GregP said:


> Delcyros, where does your graph for limiting Mach numbers come from? I see no report number ... just a graph. Is it from a flight simulator or a real report? If so, by whom?
> 
> Not saying it is wrong, just wondering.



The graph of limiting Mach numbers is mine and represent a print of my database for early jet engined A/C using SPSS. I took the figures from flight manuals of the involved planes, and in some cases, where such information was not aviable from NACA TN´s or from the statement of the aeronautic engeneers in charge in secondary sources (straight winged XP-86, Ho-IXV2, He-280 a.o.). I don´t have data for all, though. Those which are unaviable, are excluded from the print, of course.


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## delcyros (Jan 17, 2013)

> The GE J33 or the Nene was again much larger (+20%), essentially reached the size of the larger radial piston jobs, so it had to be put into the fuselage as it already grown out the wings. The next step would be an even larger engine and the fuselage starts to grow fatter, drag rises steeply and you are entering the area rapidly decreasing dividients and this point was already met in 1945. To achieve maximum speed a minimum fuselage cross section (~drag) is required.



While it is all correct, one has to give credit for the application of radial jet engines to the US and UK air forces in this period. Greg and DaveP, for good reasons, as I think, stress that the radial jet engines -albeit dead end developments- were sufficiently superior in the period under discussion that the neglect of them represents a temporary but serious technical disadvantage for the GAF.
In my mind, this perception is not entirely unjustified. I would not like to engage a Dervent V or Nene powered Meteor, P80 or Vampire in late 45/early 46 with a Jumo-004B/D powered -262A. While the -262 posess some better high altitude top speed performance and lim. Mach superiority, it suffers from poorer acceleration, climb and service ceiling. The adoption of -004E with afterburners equalizes these shortcomings at the expanse of range and endurance but prior to the advent of workable 2nd generation jet engines in form of Jumo-012, HeS011- and -013, BMW-018, Db-016 I have no difficulties to see that the germans are lacking behind -at least for a period- from mid 45 to, say ~mid 47(?).
Had the GAF adopted fuselage mounted jet engines in their first generation jet planes (they had experiences coming from the He-178 ), then the adoption of radial engines might make perfect sense. Otherwise axial is the way to go, though there is no excuse for the cancelation of the HeS030.


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## davparlr (Jan 19, 2013)

delcyros said:


> However, the design environment of the GAF called distinctly for airframes, whiches details of jet engine installation required external mounts to ease maintenance and allow for rapid replacement of worn out engines (see f.e. underwing mounts in He-280, Me-262, Ar-234 and He-162, the principal jet engined designs adopted for development in the early and mid war period. Only with the 1944 and later designed jet A/C little by little fuselage mounts became acceptable from a design point of view. We have to reckon with difficult working conditions and fear of technological failure in this period.


I understand all you say and I am sure you are correct and that is the way things were. I guess I was offering a different scenario where there was encouragement to pursue a centrifugal engine and a manufacturer like Heinkel was given the task of build an airframe for a 4-5000 lb thrust engine and, because it was easier to build and manufacture, produce in quantity a high performing jet in late ’43 what impact would it have. I don’t really want to start a new thread here, just wondering.



> Leaking engines were quite common but in a fuselage mounted one this would determine the eventual loss of the airplane. Only when safety record became advantageous this requirement was finally dropped (Ho-229, Me-P1101, Ta-183 and -Flitzer, Ju-EF128, Hs-P135 and others). It was the ultimate reason for both Heinkel and Messerschmidt beeing forced to avoid fuselage mounts for their He-280 and Me-262, respectively.


The He 178 didn’t seem to have a problem with this, nor did the Americans with the P-59 which first flew just three months after the Me 262. Anyway, a burning engine on the wing will certainly encourage a pilot to exit the aircraft, so chances are it would be lost anyway. Did the Me 262 have a problem with burning engines? I suspect the primary reason for the pod mount was for maintenance and replacement reasons like the Boeing 707 vs the Comet. The maintenance and replacement of the engine on the P-80 was probably more difficult but not much. At least it wasn't on the plastic model TV-2 I put together as a kid. 



> However, with radial engines in external mounts, frontal diameter of the jet engines very soon becomes a critical design parameter. Thus, I remain convinced that the GAF got the compromise they desired most with axial jet engines in external engine nacelles.


In general, I agree. The Brits seem to do okay with their Meteor, however. The real advantage with the bigger engine is burying it in the fuselage, reducing the cross section significantly.


> Wing root mounts for the engines were considered, too, in combination with larger wingsweep and more powerful engines (HG-III), which eventually would make the plane capable for true transsonic operation, something the P-80 never was capable of.


However, Allied designers would not be idle either and by the time new engines appeared, most likely advanced Allied engines, such as the Nene with 25% more thrust could be installed into the P-80. And, with Kelly Johnson running the program, a swept wing P-80 would be out six months after the first sighting of a swept wing German fighter (I would guess a fixed wing P 1101). 



> I will concede this point. But how much fight took place at over 40000ft altitude in ww2?


This is not the point. Higher altitude is higher energy and an area of safety and tactical advantage in that they could attack or not. Coming down the P-80 could easily reach their Mach limit which would still be faster than anything the Me 262 could reach in level flight. They would overtake the Mes and break up their formations and climb back up (they could out climb the Me at any altitude) and do it all over again, or just chase the Mes down to lower altitude where the P-80s would have better speed and climb. Chances are the Mes would pull away from the P-80s in the dive but still their attack on bombers would be broken.



> The BMW-003 also had no issues with flameout caused by rapid throttle changes due to the accelerator valve which was missing in the Jumo.


I can’t really argue this point as I don’t know. The BMW-003 seem to have too little an operational experience to make a judgment on reliability however. 



> I guess so. But do not forget that the 1944 Me-262A is quite a bit different than a late 45 or early 46 one. The improvements mentioned earlier in this thread would represent a serious enhancement of capabilities of the jet A/C and I see no reason why they shouldn´t be applied in an apple vs apple comparison.


I already talked about the engines. Other than the slightly swept back wings of the Me 262 and Me 163, I do not believe an aircraft with the sweep levels necessary to significantly increase Mach limit had ever gone through any formal flight testing (they did have a aircraft under development that could evaluate this in the P1101) so rapid adaptation of the swept wing was questionable.
I would not consider the P-84 as being “ill fated”. It certainly had its problems but so did other jet aircraft. It took the Me 262 three years from first flight to being full operational, the same time it took the F-84, 1946 to 1949 when the D became operational. Aerodynamically it was impressive, reaching 611 mph on 3750 lbs thrust, less than the Me 262 and P-80A. 



> The P84 had a significantly lower crit Mach due to it´s thick airfoil sections. Thus, any performance advantage would materialize only at Sea level altitudes where the distance to limiting Mach numbers is large. Low altitude would be avoided in air combat due to fuel consumption issues, range at high altitude in the P-80 and P84 was twice to three times higher than at Sea level. At high altitude, the 1948 P-84 with 5400lbs jet engine is not much faster than the 1944 state standart -262A and slightly slower than the [late -45] -262A with 10% uprated engines and minor aerodynamic improvements approved for mass production in feb. 45.


It certainly had its problem, especially with engines. I don’t have any sources to use to question you comment on high altitude flying. However, it did indeed have good low altitude performance and could out maneuver a Mig 15 at low altitude as reported by Col. Richard Burns at this site
1st. Lt. Richard Burns almost shot down in his F-84 in Korea « War Tales



> “One day we got in a dog fight over North Korea and I ended up with a MIG on my tail. One of our guys yelled, ‘You have a MIG right behind you,’ he said. “I knew I could out fly him if I could get down on the deck. So I came down to 5,000 or 6,000 feet and started making tight, level turns. Any time we got in trouble with a MIG on our tail we’d do this and eventually the MIG would fly away,” he said.



It seems to have been a very effective ground attack aircraft with the AF claiming it destroyed 60% of ground targets in Korea, and had several first including first aerial refueling capability, setting various records and transforming tactical response, and single pilot nuclear weapons capability. All in all, it did serve in war effectively and had an honorable career and, in my opinion, was not “ill fated”.



> At high altitude, where M=1.0 is around 660mph the P80 engages it´s limiting Mach number already at 528mph.


The only way these two planes could get close to their limiting Mach number is in a lightly loaded dive, i.e., no heavy maneuvering. Any yanking and banking would negate Mach limit as an issue. I have discussed how that this is important in escaping and engaging the enemy, but while the F-86 could easily out dive a Mig-15, the Mig 15 was still a real pest due to its higher ceiling and good maneuverability and was a formidable competitor. I do not believe the higher Mach capability was a war winning advantage over the P-80. I see the relationship of the Me 262 vs. the P-80 as similar to the F-86 vs. the Mig-15. With good low altitude capability and reasonable high altitude performance, especially in ceiling, I think that, in mass, like the Allies liked and had the capability to do, they would have quickly eliminated the Me 262 as a significant threat.

Your arguments have been well researched and reasonable and this has been an interesting discussion. I have learned a lot from research and from your arguments but I think we are getting close to our established perspectives and probably have to agree to disagree on some items.


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## davparlr (Jan 20, 2013)

Tante Ju said:


> The Derwent was already much (+20%) larger diameter (and thus drag) than German axials, which is why the Meteor was so much slower.


I don’t think so. The not much larger Derwent were aerodynamically better located semi-submerged in the wing, probably mitigating the increased frontal area of the engine. I think the main culprit in drag was the large wing, 50% larger than the Me 262. The P-59, With a much aerodynamically (probably) better located engines but with a humongous wing 65% bigger than the Me 262, was still slow as a toad.


> The GE J33 or the Nene was again much larger (+20%), essentially reached the size of the larger radial piston jobs, so it had to be put into the fuselage as it already grown out the wings. The next step would be an even larger engine and the fuselage starts to grow fatter, drag rises steeply and you are entering the area rapidly decreasing dividients and this point was already met in 1945. To achieve maximum speed a minimum fuselage cross section (~drag) is required. Look at the Nene's history, a great centrifugal engine no doubt, but essentially it stuck right where it started, even the version in the MiG 15 did not improve much on its thrust.


The J-48/Tay engine maxed out at 7250 lbs thrust dry and was the same diameter as the J-33/Nene, an impressive 45% increase in thrust and powered the 1953 F9F Cougar. At this time the axial engines actually caught up with the centrifugal engines in thrust and thrust to weight. The BMW 003/SNECMA ATAR engine generated 7490 lb thrust, dry, for the Super Mystere B.2 in 1955, with a thrust to weight ratio roughly two/thirds the J-48. And the ATAR was developed with the assistance of German engineers and scientist.
Aeronautical Research in Germany: From Lilienthal until Today - Ernst Heinrich Hirschel, Horst Prem, Gero Madelung - Google Books



> See the pattern here? Centrifugal jet engines were dead end and extremely limited development potentional for fighter applications,


Dead end? Yes, As was the Me 262. That does not mean they were not the right answer at the right time. The centrifugal engine was more than competitive until the advent of Mach aircraft, at which time the diameter became critical and efficiencies of the axial engines exceeded that of the centrifugal engines. This was approximately early to mid-fifties, even with German development.


> basically the way they increased output meaningfully was increasing the size (diameter) of the engine.


 This seems not to be true with the Nene-to-J-48 upgrade.


> Thrust to weight ratio is interesting and a good T/W is useful for improving climb, but does next to nothing to improve top speed, especially at jet top speeds, which was what jets were all about. Even T/W ratio had less importance with jets than with prop jobs since the jets made their best climb at about twice the speed than prop jobs where induced drag is far less dominant.


I was an Avionic manager/engineer for 29 years working for a prime contractor company whose main customer was the military. I have designed and developed and had installed hardware for aircraft ranging from light supersonic fighter aircraft (F-5E, F-35), research aircraft (Tacit Blue) to heavy bombers (B-2) and heavy transport aircraft (Joint STARs). I can assure you that I have sweated blood for every pound for every program. I can also assure you that one of the main efforts of every program manager is a parameter line typically called weight management.

Weight is an insidious problem. Every pound increase must be made up in performance or in design. To maintain range (something very important to early jets) fuel must be added, more fuel means even more weight. To maintain maneuvering capability and ceiling more wing must be added. More wing means more weight. To maintain acceleration (another issue with early jets) a stronger engine is needed. A stronger engine may require more structure. Both require more weight. And the iteration with the new weight keeps on going. Or, you could just accept slower climbing, less maneuvering, lower combat ceiling, longer takeoff runs, faster approach speeds, and less range, and probably others. I stated earlier that the engine in the P-80 was about 1400 lbs lighter than the two engines of the Me 262. That’s equal to a really big bomb being carried around all the time, or carrying six additional crew men. That’s a big load for a 40’s era jet plane.

Please excuse me for expounding. It is just that I have too many management whip scar across my back that starts hurting when someone minimizes the impact of weight gain on an aircraft.


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