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P-80 versus Me. 262???


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#1 ickysdad

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Posted 29 August 2009 - 03:10 AM

Which is better any good numbers for thse two's performance???

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#2 Pete57

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Posted 30 August 2009 - 08:45 PM

The two aircraft were, in many ways, pretty evenly matched.
Level speed (mph/ft)
Me-262: 484/0, 502/7500, 513/12900, 525/13700, 525/16300, 529/17400, 519/20000, 513/26600, 518/3200 (RAE Report Avia 6/9201 and TsAGI tests)
P-80A: 510/0, 514/5000, 524/15000, 534/25000, 512/34900, 494/39900 (USAAF Memo Rep. No. TSFTE-2009)
Climb Rate (fpm/ft)
Me-262: 3000/1900, 2800/4400, 2680/6700, 2600/9100, 2350/9600, 2070/12600
P-80A: 4900/0, 4500/5000, 4000/10000, 3600/15000, 3200/20000, 2750/25000

The Schwalbe had a slightly higher critical mach, 0.83 (0.80 for the P-80A), which, in a hypothetical dogfight, would give it a chance to escape the Shooting Star in a dive (the US fighter had a higher ceiling).
Unfortunately (for the 262) its lack of airbrakes would translate this in either a final dive or give the P-80 the chance to catch up!

Some sources claim the 262 had a better acceleration, but this may have stemmed from taking at face value the cross-tests the USAAF had run, after the end of the war, between a specially prepared Me-262 (e.g its paint polished, etc) against the early, De Havilland Goblin-powered XP-80 prototype.
Just consider the following:
a. With about the same total thrust, the P-80A was about 2000lb lighter.
b. The Shooting Star had a lower drag area - 3.20 sqft, against the Schwalbe's 4.68 sqft
c. The spool-up time of the centrifugal turbojets of the time was lower than their axial counterparts’'.
And then tell me if the statement on the 262's superior acceleration shouldn't be questioned...

The P-80A had a very high roll rate, said to be pretty close to that of the FW-190, whereas the 262 with its wing mounted pods must have been anything but a stellar performer in this field.

So far as istant and continuous turn rates are concerned, I haven't been able to find the relevant figures, but as a general rule, single engined fighters tend to be more manouverable than twins.

The 262 packed a far heavier punch, but it was less suited, for a dogfight, than the P-80A's and this shows the different roles for which the two aircraft had been conceived: the 262 was a bomber-destroyer, whereas the P-80 was an air-superiority fighter, and in the end, this is why, comparing the two, is a little like comparing apples with oranges.

However, had the war continued to the point where the P-80A could be sent to escort the heavies over Germany, this comparison could be seriously considered, as the ascendancy the 262 had begun to establish over the Allied bomber force could have seriously been put into jeopardy - nice 'what if' ain't it?...

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#3 ickysdad

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Posted 30 August 2009 - 09:57 PM

Where can I get copies of all those tests??

#4 Kutscha

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Posted 30 August 2009 - 11:37 PM

The 262 was not specially prepared Pete but was flown as received from Watson's Wizards. The P-80 certainly was.

Ickysdad, the report is hard, if not impossible, to find for the USAAF hid it away after the Wright Field test flight(s) because it was not favorable to the P-80. Hughes wanted to race a 262 in a race and was told he couldn't because it might be embarrassing for the P-80.

This book, Messerscmitt Me262, WJ Boyle, ISBN 0-87474-276-3, touches on the test briefly.

#5 ickysdad

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Posted 31 August 2009 - 03:03 AM

The 262 was not specially prepared Pete but was flown as received from Watson's Wizards. The P-80 certainly was.

Ickysdad, the report is hard, if not impossible, to find for the USAAF hid it away after the Wright Field test flight(s) because it was not favorable to the P-80. Hughes wanted to race a 262 in a race and was told he couldn't because it might be embarrassing for the P-80.

This book, Messerscmitt Me262, WJ Boyle, ISBN 0-87474-276-3, touches on the test briefly.



That doesn't make any sense since there have been far bigger embarrasments and besides Chuck Yeager flew both and stated both were basically equal & he was one of the test pilots involved if I'm not wrong. I don't expect to find anything that says either one was outright superior to the other but just would like to have some hard numbers.
I mean if it's so hard to find then how can anybody know it's not favorable to the P-80? How can one know the Me 262 wasn't specially prepared but the P-80 was?

#6 GregP

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Posted 31 August 2009 - 04:12 AM

Hi guys,

I posted in this thread Saturday evening and it disappeared!

I pretty much agree with Pete57. The P-80A was a very good airplane for its time and the Me 262 is often credited with qualities it didn't have ... even supersnic speed according to some!

As an old aeronautical engineering student for 3 years before switching to electrical engineering, I can tell you it is NOT supersonic.

A game changer? Yes. Thef first deployed jet fighter? Yes.

But the best of the early jets? I don't think so. The two aircraft were very close in performance, with the P-80A getting the edge in my book.

However, they never met in combat.

Somehow I wish the Me 262 had been developed past the end of the war, just see what would have evolved. I think the single-engine fighters would have been better by and large, but the Germans were pretty darn good at making things work the way they wanted them to work, so we don't really know.

In the end, I can't think of a single successful fighter with twin engines in pods under the wings after the Me 262 ... and it was on the losing side of thw war. The closest was the Meteor, but the engines were buried in the wings, not in underslung pods. Still ... it WAS a pretty good unit for the time, and the Me 262 may well have been as good as all the hype.

But let's remember, the hype from the war was from pilots flying piston mounts while watching a jet go by. If they had been flying jets instead, the outcome and the reports may well have been different. In fact, they weren't and we are left with the hype.

Given the choice, I'd opt for the P-80A, but I would not feel disadvantaged if offered the Me 262 instead. Methinks the pilot would have been the deciding factor ... well, that and the location of the fuel truck.

The fight I would like to have seen is the Meteor against the He 280. Very similar airframes.

#7 Pete57

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Posted 31 August 2009 - 08:48 AM

The 262 was not specially prepared Pete but was flown as received from Watson's Wizards. The P-80 certainly was.

Ickysdad, the report is hard, if not impossible, to find for the USAAF hid it away after the Wright Field test flight(s) because it was not favorable to the P-80. Hughes wanted to race a 262 in a race and was told he couldn't because it might be embarrassing for the P-80.

This book, Messerscmitt Me262, WJ Boyle, ISBN 0-87474-276-3, touches on the test briefly.


From http://www.indianami...62A1U3/4012.htm

"This aircraft [FE-4012]was surrendered to US Forces at Lechfeld and was named Connie the Sharp Article, with the number '444'. It was later re-named Pick Il by Watson's Whizzers. It came to the USA aboard HMS Reaper and was flown from Newark to Freeman Field IV Col Watson on 19th August 1945. While at Freeman Field it was reconditioned and given an overall smooth finish for performance comparison with the Lockheed P-80. This process almost certainly involved the removal of its photo-reconnaissance-type nose and its replacement by a fighter-type nose without camera bulges."
A reference to the results of the P-80A/Me-262 tests can be found at http://warbirdsforum...ght=jets&page=2

The figures I've posted for the P-80A are for S/N 44-85044, and they were considered as being representative of the standard, production aircraft, the report stating "The performance reported is representative of the production P-80A-1 airplanes"

It is interesting to compare it with the performance of P-80A-1 S/N 44-85123, winner of the 1946 bendix trophy, which was especially well maintained.
This a/c was also modified with reduced-span wings and a new nose section with airbrakes removed, providing the following results (Memorandum TSETE-2042 on Dec. 3, 1946 - mph/ft)
Standard wing & nose (G/W 11750lb): 548/2700, 546/7600, 542/12000, 501/34700
Mod. nose & std wing (G/W 11560lb): 556/2700, 554/7600, 550/12000, NR/34700
Mod. nose and wing (G/W 11480lb): 562/2700, 561/7600, 557/12000, 505/34700

Another series of tests was run in 1947 to determine the effects on the overall performance of the engine thrust and the aerodinamically efficient but expensive to maintain, smooth paint that was being used on the early P-80A's, the results being summarized in the Memorandum Report TSFTE-2053, on Feb. 14, 1947.
The aircraft involved were S/N 44-85075, S/N 44-85044 using two different engines, for these tests, 44-85123, all of these painted, and S/N 44-85462, un-painted.
Speed/altitude (mph/ft)
44-85075: 524/5000, 523/20000, 490/35000
44-85044 (engine #1): 514/5000, 520/20000, 507/35000
44-85044 (engine #2): NR/5000, 537/20000, 512/35000
44-85123: 548/5000, 531/20000, 500/35000
44-85462: 525/5000, 522/20000, 502/35000
The results showed how a well maintained paintwork could offset, in terms of maximum level speed, its extra weight.

ickysdad all these reports can be found at http://www.wwiiaircr...erformance.org/

Greg I wholehartedly agree on the He-280/Gloster Meteor what-if, and I do believe that had the Luftwaffe decided to put the 280 into production, delivering the early examples to some Eprobungskommando, sometimes in late 1942-early1943, then the RAF would have pushed harder for the Meteor's development which, according to a Frank Whittle interview, could have also been put into service earlier.

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#8 Kutscha

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Posted 31 August 2009 - 11:13 AM

Col Al Boyd:
There was no comparison as far as I'm concerned between the operational capability of the Me262 and P-80. There was nothing comparable with the Me262 in Britain or the US. It was another couple of years before the P-80 began to approach it.

Boyd was one of the test pilots and was cautioned not to release his findings.

Are you going to argue with the test pilot who did the testing?

The conclusion of the official report on the tests were also censored. They stated: "Despite a difference in gross weight of nearly 2000lb, the Me262 T2-711 was supior to the average P-80A in acceleration, speed sand approximately the same in climb... The Me262 apparently has a higher critical Mach number, from a drag standpoint, than any other current Air Force fighter."

Btw, there is a big difference between cleaned up, the a/c had been sitting around, and 'specially prepared'. The Me262 received an extensive refurbishment and a high gloss paint job when returned to Hughes.

The race Hughes wanted to enter was the 1948 Bendix Thompson Jet Trophy Races with the only competition being P-80s. Again, do you want to argue with Col. Watson who stated that Gen. Arnold stopped the Me262 from being entered because it could potentially be an embarrassment to the fledgling Air Force.

pg 854 of Me262 by Smith and Creek

#9 ChrisMcD

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Posted 31 August 2009 - 12:56 PM

The race Hughes wanted to enter was the 1948 Bendix Thompson Jet Trophy Races with the only competition being P-80s. Again, do you want to argue with Col. Watson who stated that Gen. Arnold stopped the Me262 from being entered because it could potentially be an embarrassment to the fledgling Air Force.

pg 854 of Me262 by Smith and Creek


This ties in with what I have read. Hughes Aircraft released a number of publicity photographs and were treating the 262 as their own property. IIRC their intention of entering it for the Bendix trophy was the last straw and they were reminded that it was government property and had to be returned.

Arnold had a feud on with Howard Hughes dating back to the start of the war, which probably contributed to the decision.

http://books.google.... arnold&f=false

Which may also explain why Hughes aircraft were absent from WWII to any great extent!

#10 ickysdad

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Posted 31 August 2009 - 03:41 PM

Several other sources disagree with the book "Me. 262" and Chuck Yeager who flew both aircraft(the YP-80A & me. 262) says they were essentially equal . Have any of you thought those test pilots were told what to say in order to get more funding for the USAAF post war? Funds were quite hard to get then and there's nothing like saying something to the point of " Hey the Soviets captured some of the same and it's already way ahead of anything we got" to get Congress tom approve more funds.Furthermore a book about the Me 262 maybe just a little bit biased . You hear tid bits of what people who are involved with a project say but it would be nice to actually read the report with hard figures and I really doubt the so-called USAAF's "embarrasment" would be ongiong after 60+ years .
This is why I mainly try to rely on primary documents. Also in reading Eric Browns "Wings of the Luftwaffe" & other works it seems the Me. 262 had ALOT of operational issues that one never seems to hear.

Edited by ickysdad, 31 August 2009 - 03:56 PM.


#11 ickysdad

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Posted 31 August 2009 - 04:38 PM

If the loaded/combat version of the Me 262 was superior in acceleration/speed ,had a higher mach number, and was equal in climb to the P-80 then why would the uSAAF bother to follow that test with one that pitted the P-80 against a stripped down recon version of the Me262? The USAAF would already know that a stripped down Me 262 would have better performance then a loaded/combat version which they had already tested and found superior to the P-80. Yet that's what one reads all the time in comparing the two.
Also in the statement I'm referring to above it states the Me 262 is "superior" but just what does "superior" mean? 5 MPH?? 10 MPH??? 15 MPH??? Higher mach number???? Is it .86 as compared to mach .84??? >9 to .88??? Just how much is "superior"??? So one plane is faster,accelerates better ,has higher mach number and is equal in climb the other a/c maybe be a better diver, roll better ,turn better,zoom climb better ,so all in all equal to one another. Furthermore one a/c may have a higher mach number but that doesn't make it a better diver especially if the one with a higher mach number doesn't have dive brakes. The Spitfire XIV is credited with having a higher mach number then a P-51 or P-47 but tests conducted by the British showed the 2 USAAF fighters were still the better divers. I guess the plane with a lower mach number in possessing an initial dive acceleration would be long gone before the mach number becomes an issue.

#12 Pete57

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Posted 31 August 2009 - 08:55 PM

Col Al Boyd:
There was no comparison as far as I'm concerned between the operational capability of the Me262 and P-80. There was nothing comparable with the Me262 in Britain or the US. It was another couple of years before the P-80 began to approach it.

Boyd was one of the test pilots and was cautioned not to release his findings.

Are you going to argue with the test pilot who did the testing?


It seems to me that Boyd was referring to the operational capabilities of the two aircraft and, given that several hundred 262 had been delivered to operational units whereas the P-80A had only served with the 1st FG at Lesina, Italy in a grand total of two examples, his statement was more than correct.

The conclusion of the official report on the tests were also censored. They stated: "Despite a difference in gross weight of nearly 2000lb, the Me262 T2-711 was supior to the average P-80A in acceleration, speed sand approximately the same in climb... The Me262 apparently has a higher critical Mach number, from a drag standpoint, than any other current Air Force fighter."

The 262 was limited to M0.83-0.84, which was a whopping M0.04 higher than the P-80A (a 3.75-4% increase) and speaking of drag, the 262’s zero-lift drag (CD0) was 0.020, whereas the P-80A’s was 0.0134 (33% lower) so, I would say, the P-80A could out accelerate the 262 up to a speed of probably around M0.75, when aileron-buzzing would possibly appear, with the 262 getting the upper hand beyond.

Btw, there is a big difference between cleaned up, the a/c had been sitting around, and 'specially prepared'. The Me262 received an extensive refurbishment and a high gloss paint job when returned to Hughes.

The refurbishment and the paint job were given by the USAAF, to match the P-80A’s finish so as to make the cross tests a balanced affair.

The race Hughes wanted to enter was the 1948 Bendix Thompson Jet Trophy Races with the only competition being P-80s. Again, do you want to argue with Col. Watson who stated that Gen. Arnold stopped the Me262 from being entered because it could potentially be an embarrassment to the fledgling Air Force.

pg 854 of Me262 by Smith and Creek

One of the aircraft to race at the 1948 Bendix Trophy was a NA F-86 Sabre, flown by Air Force Major R. L. Johnson who, although failing to officially establish a new record due to recording equipment failure, managed to exceed USMC Major Carl’s record by almost 20mph, flying his standard Sabre at a speed of 650.796mph, well beyond the 262’s possibilities, so there would have been no possibility for the Air Force to suffer any embarrassment…

I would rather consider two factors:
1. Hughes’ attitude, which had not endeared him to many high-ranking officers and even lower-ranking personnel, as he often behaved like the Air Force was merely another “branch” of Hughes Aircraft Co. I have read someplace that, one day, Hughes showed up to fly one of the Bell P-59 Airacomets – the US’ first jet – which at the time was still a rather secret aircraft undergoing tests, and the line-personnel had to come up with a phony problem in order to temporarily ground the aircraft and keep the tycoon from “flying our aircraft”!
2. Hughes was a very good pilot but, at the time of the races, he had logged very little (if any) jet-time: think what would have happened, had Hughes crashed the 262 going ‘balls out’ (not rarely his way of flying) and losing his life, with the armed forces being very PR-conscious in the attempt to do their best to ensure a share in a shrinking military budget.
Wouldn’t the death of such an influential character have spelled catastrophe for the Air Force?

I’d like to end my post by quoting the analysis on the Me-262, by Dennis R. Jenkins, author of the Warbird Tech #6 on the Messerschmitt Me 262 Sturmvogel, that, in my opinion, best summarizes it:
“The Me 262 certainly deserves its place in history as the first operational jet fighter. Given the severe constraints placed on wartime Germany, it was a remarkable aircraft. However, both British and American jet fighters were under development, and their production could have been accelerated if the war situation had dictated a need for their capabilities. As it was, the Allied
bombers and piston-engine fighter escorts developed tactics that largely negated the advantages enjoyed by the Me 262. Given the limited numbers of the German jet fighters, there was no way they could materially effect the outcome of the war when they finally arrived on the scene in 1944.
Given the time and resources, the Germans could have refined the Me 262 into a more effective aircraft, but the Allies had infinitely more time and resources to develop their own more effective aircraft. Late in the war, it was a game the Germans could not win.”

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#13 curmudgeon

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Posted 31 August 2009 - 11:59 PM

Maybe we need a more general 'early jets' discussion.

It is very hard to actually track down information on this period as references tend to mix mark numbers or to cite performance of post-war aircraft. Engine capability and design were both advancing very rapidly and performance changed swiftly (e.g. Meteor F1s had a top speed around 400mph, the F3, less than 6mo later, was around 500mph ... and considerably more fitted with the long nacelles).

The He280 was dropped by the Germans, but cited reasons are in conflict.

The Me262 started early but had many teething problems wrt its design and airframe as well as its engines (under performing, very low life, instabilities).

The Gloster Meteor was developed slowly and there were early engine problems (the original flew with Halford engines pinched from de Havilland). It was the first operational fighter, entering squadron service weeks before the Me262 and remaining in squadron service for the rest of the war (the Me262 entered service from experimental units and was then withdrawn late in 1944 for further development). Performance of the Meteor F1 was disappointing, but the F3 (Dec 1944) was a capable aircraft. Extension of the nacelles (the F4 standard) reduced drag and markedly improved performance. The modification was fitted to aircraft in the field ... but did this happen by May 1945?

The de Havilland Vampire had good performance but started later than the Meteor and again had unhurried development. It was originally viewed as an experiment but forced itself into contention as a combat aircraft on speed, general performance, range, and ease of handling and servicing. The production variant appeared in April 1945, but (with the end of the war) didn't enter squadron service until 1946.

The P59 turned out to be an experiment ... it wasn't meant to be, but its performance was poor.

The P80 was last aboard, three? aircraft being shipped to Europe for the last weeks of the war. As a design it was remarkably durable, spawning a range of variants in the late 1940s (e.g. the Starfire) as well as the T33. By the late 1940s it had been up-engined and tweaked and was superior in most facets to the Meteor or Vampire (development of which had frozen due to Britain's parlous financial circumstances and the prospect of generation 2 jets)

#14 GregP

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Posted 01 September 2009 - 01:11 AM

Would I disagree with a 1940's test pilot? Yes, if I thought he was wrong.

We know a LOT more about aerodynamics today than Boyd did back then.

Most "official" reports of captured enemy aircraft are VERY biased.

When we captured a MiG-15 in Korea (actually, it's pilot defected), Chuck Yeager flew it. His report was to give US pilots a morale boost.

What was he supposed to say, "Great fighter! Better than ours, higher-flying and more maneuverable?"

Methinks the Air Force would NOT have allowed that, no matter what. In point of fact, the MiG-15 is almost the exact equal of the Sabre. It is better at some things and teh Sabre is better at others. As for which is the better fighter, it SERRIOUSLY depends on which one the pilot making the report flew for his country.

Kutscha, I am not denigrating the Me 262; it was a great plane in its own right.

But neither do I think it was better in any significant way than the P-80A. In speed they were almost a dead heat except for critical Mach number, which VERY marginally favored the Me 262. The P-90A had a higher servic e ceiling so, at SOME point, it outclimbed the Me 262.

Again, this is a "what if" since they never met in combat ... so, I'd say we have to agree to disagree here. The wartime Me 262 was placarded at 540 mph, just the same as the "new build" units are. The wartime P-80A was a bit faster than that.

I'd take a P-80A in a dive anytime since it did not have the reputation of diving into the ground when overspeeded. But the Me 262 was a great mount in which to go fight in the 1944 - 1945 timeframe. Had I the choice, I'd opt instead for a Focke Wulf Fw 190D or a Ta 152 ... if only becuase of engine reliability.

#15 Ricky

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Posted 01 September 2009 - 07:08 AM

Just an aside - the discussion about Boyd's comments. If he was asked to keep his commens to himself, then they are not likely to be the biased "let's buck our boys up" kind of report, but his honest assessment.

His honest assessment is not necessarily correct, but that's a different argument:p

#16 ickysdad

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Posted 01 September 2009 - 04:57 PM

Just an aside - the discussion about Boyd's comments. If he was asked to keep his commens to himself, then they are not likely to be the biased "let's buck our boys up" kind of report, but his honest assessment.

His honest assessment is not necessarily correct, but that's a different argument:p


His comments came at a time when the USAAF was trying to get funds & such . So why not not make out the performance of US aircraft to be so bad that the USAAF needs more funds? This happens everyday with all 4 services.

#17 ChrisMcD

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Posted 01 September 2009 - 07:13 PM

But neither do I think it was better in any significant way than the P-80A. In speed they were almost a dead heat except for critical Mach number, which VERY marginally favored the Me 262.


IIRC there was a comment that the 262's wing section was used by NA for the Sabre.

I have been doing some searching and there is an interesting site
http://www.public.ia...rfoil_usage.htm

Which gives the Sabre's as NACA 0009.5-64 (Root) and NACA 0008.5-64 ( Tip)

and the 262's as NACA 00011-0.825-35 NACA 00009-1.1-40

So, are these similar airfoils or not? If so they imply that - if the Sabre was supersonic in a dive, perhaps the 262 could do it as well?

There is a further comment that NA cannabalised some real 262 slats to test on early Sabres to improve low speed handling, so I could be confused by that.

But if the 262 did have a very good airfoil it might explain why the 262 was supposed to be so much faster than more powerful competitors

#18 Trexx

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Posted 01 September 2009 - 07:52 PM

ChrisMcd, I've read that somewhere also. Furthermore, the F-86 was originally concieved as a straight wing airplane. Very late in it's design phase was it re-worked to be a swept wing jet. This happened as German data on airfoils, swept wings and wing loading became available (as well as wing construction). Three other airplanes have had influence in almost identical circumstances: The B-47, B-52 AND the Boeing 707.

#19 Pete57

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Posted 02 September 2009 - 08:58 AM

[

IIRC there was a comment that the 262's wing section was used by NA for the Sabre.

I have been doing some searching and there is an interesting site
http://www.public.ia...rfoil_usage.htm

Which gives the Sabre's as NACA 0009.5-64 (Root) and NACA 0008.5-64 ( Tip)

and the 262's as NACA 00011-0.825-35 NACA 00009-1.1-40

So, are these similar airfoils or not? If so they imply that - if the Sabre was supersonic in a dive, perhaps the 262 could do it as well?

By the same token, the P-80 family could have been supersonic in level flight, as it used the NACA 65-XXX series, possibly similar to the Bell X-1’s NACA 68-XXX series.

In reality, it takes more than just choosing the right airfoil to go supersonic.
You can use a very thin, straight wing, like the Lockheed F-104, the Bell X-1 family, or the North American X-15, or you can take a wing of moderate thickness and sweep it back.

From wikipedia: “The idea of using swept wings to reduce high-speed drag was first developed in Germany in the 1930s. At a Volta Conference meeting in 1935 in Italy, Dr. Adolf Busemann suggested the use of swept wings for supersonic flight. He noted that the airspeed over the wing was dominated by the normal component of the airflow, not the freestream velocity, so by setting the wing at an angle the forward velocity at which the shock waves would form would be higher (the same had been noted by Max Munk in 1924, although not in the context of high-speed flight).
Albert Betz immediately suggested the same effect would be equally useful in the transonic. After the presentation the host of the meeting, Arturo Crocco, jokingly sketched "Busemann's airplane of the future" on the back of a menu while they all dined. Crocco's sketched showed a classic 1950's fighter design, with swept wings and tail surfaces, although he also sketched a swept propeller powering it”

Moreover, an appropriate sweep maintains the wing inside the mach-cone generated by the aircraft’s nose, avoiding the situation were some parts of the airframe are subjected to a supersonic flow while others are subjected to a subsonic one.

At the end of the conflict, German aerodynamicists were trying to determine the best sweep to go supersonic and the Messerschmitt P-1101, a ground-variable geometry aircraft was to be used to practically determine the ideal wing-sweep: the wing could be set at the two values of 35° and 45° probably as a result of the supersonic wind-tunnel tests.

The scientific “bounty”, taken from Germany turned out to be a bonanza to the Allied and Soviet aircraft designers.
Again from wiki:
“Von Kármán travelled to Germany near the end of the war as part of Operation Paperclip, and reached Braunschweig on May 7, discovering a number of swept wing models and a mass of technical data from the wind tunnels. One member of the US team was George Schairer, who was at that time working at the Boeing company. He immediately forwarded a letter to Ben Cohn at Boeing stating that they needed to investigate the concept. He also told Cohn to distribute the letter to other companies as well, although only Boeing and North American made immediate use of it.”

At the same time, though, NACA was no stranger to this theory either (again from wiki):
“In February 1945 NACA engineer Robert T. Jones started looking at highly-swept delta wings and V shapes, and discovered the same effects as Busemann. He finished a detailed report on the concept in April, but found his work was heavily criticised by other members of NACA Langley, notably Theodore Theodorsen, who referred to it as "hocus-pocus" and demanded some "real mathematics". However, Jones had already secured some time for free-flight models under the direction of Robert Gilruth, whose reports were presented at the end of May and showed a fourfold decrease in drag at high speeds. All of this was compiled into a report published on 21 June 1945, which was sent out to the industry three weeks later. Ironically, by this point Busemann's work had already been passed around.”

And the evidence shows that Jones was not the only one (from http://www.bellx-2.c.../article.html): “In late 1944, the Engineering Division at Wright Field expressed their interest in high-speed swept-wing aerodynamics to which Bell responded with their proposed Model 37D. The Model 37D was a 40 degree swept-wing warmed-over version of the XS-1. After wind-tunnel tests and structural analysis it was determined that this up-grade modification to the XS-1 was impractical. This proposal was ultimately rejected by the AAF.”

Lastly, I’d like to add that the right airfoil and wing sweep may still not be enough to go beyond M1, as proved by the Soviet MiG-15 which, although desiged for supersonic flight (in a dive), was limited to M0.98 (IIRC) by instability and lack of sufficient contol issues in the high subsonic flight envelope, and forced the Soviet designers to modify the aircarft with speed brakes that automatically opened at M0.98!

There is a further comment that NA cannabalised some real 262 slats to test on early Sabres to improve low speed handling, so I could be confused by that.

IIRC, NA tested a whole slatted, wing section of the 262 by I don’t recall 262’s slats were ever mounted on the XP-86.

But if the 262 did have a very good airfoil it might explain why the 262 was supposed to be so much faster than more powerful competitors

Was it?

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#20 ChrisMcD

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Posted 02 September 2009 - 12:36 PM

Hi Pete,

Just some further comments - I am not an aerodynamicist, so am a bit wary about being too dogmatic, especialy about an American plane I do not know that much about.

By the same token, the P-80 family could have been supersonic in level flight, as it used the NACA 65-XXX series, possibly similar to the Bell X-1’s NACA 68-XXX series.

In reality, it takes more than just choosing the right airfoil to go supersonic.

Lastly, I’d like to add that the right airfoil and wing sweep may still not be enough to go beyond M1, as proved by the Soviet MiG-15 which, although desiged for supersonic flight (in a dive), was limited to M0.98 (IIRC) by instability and lack of sufficient contol issues in the high subsonic flight envelope, and forced the Soviet designers to modify the aircarft with speed brakes that automatically opened at M0.98!


That was my point. On 'old fashioned' asymmetric airfoils the rearward movement of the pressure over the top of the wing meant that the aircraft 'nosed up' as it accelerated - so choosing the right airfoil does at least mean that you are not prevented from going supersonic.

IIRC The 262 was one of the first to have a symmetrical airfoil,
http://www.zenoswarb...lotHandbook.pdf
even if it's wing sweep had more to do with moving it's C of G than speed.

I was curious as to whether NA had copied the airfoil from the Me 262. After all, that wing was a rush job to convert the straightwing Fury to the swept wing Sabre.

Whoever did the article on the Sabre in Wikipedia certainly thinks so!

http://en.wikipedia....wiki/F-86_Sabre

[IIRC, NA tested a whole slatted, wing section of the 262 by I don’t recall 262’s slats were ever mounted on the XP-86.


Could be an urban myth, but it is very widespread!

http://www.military-...-f-86-sabre.htm


But if the 262 did have a very good airfoil it might explain why the 262 was supposed to be so much faster than more powerful competitors

Was it?


Well it was a hell of a lot faster than the Meteor 1!

On a more general point. With the honourable exception of the P 38, I do not feel that Lockheed were very good at designing fighters. Both the P 80 and the F 104 were massively outbuilt by approximately contemporary designs from competitors ie the F 86 and the Phantom




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