Experimental German planes

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

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.

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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).

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.

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?

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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.

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.

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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.

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.

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.

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.

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.

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...



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

Dang those pesky Germans...

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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.

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.

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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.

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.

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?

nuuumannn said:

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

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

GrauGeist said:

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

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

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.

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.

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.

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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.

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.

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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.