Experimental German planes

[delcyros]

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.

 

[oldcrowcv63]

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.

 

[oldcrowcv63]

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.

 

[Shortround6]

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.

 

[bobbysocks]

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.

 

[GrauGeist]

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.

 

[GregP]

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.

 

[GrauGeist]

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.

 

[oldcrowcv63]

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.

 

[GrauGeist]

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

 

[oldcrowcv63]

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?

 

[GregP]

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.

 

[GrauGeist]

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

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:

 

[bobbysocks]

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.

 

[nuuumannn]

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.

 

[oldcrowcv63]

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.

 

[GrauGeist]

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...

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.

 

[delcyros]

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?

 

[Shortround6]

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.

 

[fastmongrel]

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.