Best Jet of WW2?

[DerAdlerIstGelandet]

I would go with one of the 3 here: Messerschmitt Me-263, Messerschmitt Me P.1101 or the Focke Wulf Ta-183.

[delcyros]

Umm, I should rather say: "..in level flight.." or not?
Me-263: The soviet I-270 (modified Me-263-copy) was unable to break Mach 1, but it was also a larger, heavier design with less thust and usual wing configuration. The critical Mach figure of the Me-263 is comparably low, the tailles design would be very problematic...
Me-P1101: Lacks thrust to overcome the drag at high subsonic speeds (maybe in a dive?), but still an interesting choice.
Ta-183: Lacks thrust as the Me-P1101, taildesign seems to be critical (not sure in this) in terms of statics.

[wmaxt]

Originally Posted by delcyros

Umm, I should rather say: "..in level flight.." or not?
Me-263: The soviet I-270 (modified Me-263-copy) was unable to break Mach 1, but it was also a larger, heavier design with less thust and usual wing configuration. The critical Mach figure of the Me-263 is comparably low, the tailles design would be very problematic...
Me-P1101: Lacks thrust to overcome the drag at high subsonic speeds (maybe in a dive?), but still an interesting choice.
Ta-183: Lacks thrust as the Me-P1101, taildesign seems to be critical (not sure in this) in terms of statics.

There is a story in "Planes and Pilots of WWII" That states the F-86 prototype broke the sound barrier several months prior to the X-1 (in a dive ov course. the F-86 was "transsonic" not supersonic.).

[delcyros]

I read it, too. There were many claims to have broken the sound barrier earlier than 1947:
1945: Highest recorded Me-163 (B) speed during interception (accidently): IAS(recorded): 1130 Km/h (in a dive, far beyond it´s critical Mach speed)
1945: Gerhardt Mutke at an Me-262 A dive, IAS(after Mutke): 1150 Km/h (also beyond it´s critical Mach speed)
late 1945: US pilots notes of the captured Me-262 include the following sentence: "...close to Mach speed you loose controll, the plane pitches down strongly. Once exceeded, you regain controll.."
1947: F-86 exceeds Mach 1 in a dive
1947: X-1 with civilian test pilot is said to have broken Mach 1

-None of these claims are confirmed by an independend source, but they remain very interestingly...-

1947: X-1, piloted by Chuck Yeager breaks Mach 1

[FLYBOYJ]

George "Wheaties" Welch was the guy who broke the sound barrier the days before Yeager did it. I've heard stories that "Wheaties" was always bitter about his Air Force career and kind of had a chip on his shoulder. Put him together with the outspoken Yeager and you had a set-up for an argument. When I lived close to Edwards AFB a few years ago I heard from some old timers who worked at Edwards (Muroc) during that time that Yeager and Welch couldn't stand each other! The legend has it the Welch knew about the X-1 and record attempt and he went out over Edwards in an XF-86 and purposely broke the sound barrier, just to show Yeager up. It is rumored that the air force altered XF-86 test records by 7 months! Welch died a few years later testing the F-100. Check out this link: http://home.att.net/~historyzone/Welch2.html

Originally Posted by delcyros

I read it, too. There were many claims to have broken the sound barrier earlier than 1947:
1945: Highest recorded Me-163 (B) speed during interception (accidently): IAS(recorded): 1130 Km/h (in a dive, far beyond it´s critical Mach speed)
1945: Gerhardt Mutke at an Me-262 A dive, IAS(after Mutke): 1150 Km/h (also beyond it´s critical Mach speed)
late 1945: US pilots notes of the captured Me-262 include the following sentence: "...close to Mach speed you loose controll, the plane pitches down strongly. Once exceeded, you regain controll.."
1947: F-86 exceeds Mach 1 in a dive
1947: X-1 with civilian test pilot is said to have broken Mach 1

-None of these claims are confirmed by an independend source, but they remain very interestingly...-

1947: X-1, piloted by Chuck Yeager breaks Mach 1

Airspeed indicators of the time were not capable of giving accurate readings at high fractions of mach. Also, when diving, the delay in the mechanism which adjusts for pressure will give a falsly high reading, since it is applying the airflow at the actual pressure to the equlibriums of a lower pressure from a higher altitude.

So these claims of high airspeeds are probably false. The pilots were not lying, the instruments were!

=S=

Lunatic

Originally Posted by FLYBOYJ

George "Wheaties" Welch was the guy who broke the sound barrier the days before Yeager did it. I've heard stories that "Wheaties" was always bitter about his Air Force career and kind of had a chip on his shoulder. Put him together with the outspoken Yeager and you had a set-up for an argument. When I lived close to Edwards AFB a few years ago I heard from some old timers who worked at Edwards (Muroc) during that time that Yeager and Welch couldn't stand each other! The legend has it the Welch knew about the X-1 and record attempt and he went out over Edwards in an XF-86 and purposely broke the sound barrier, just to show Yeager up. It is rumored that the air force altered XF-86 test records by 7 months! Welch died a few years later testing the F-100. Check out this link: http://home.att.net/~historyzone/Welch2.html

Breaking the sound barrier in a dive would not really count anyway. Anyone could have done it. Just build a bullet shaped metal basket and drop it from 30,000 feet and walla - you will break the sound barrier - then release part of the basket at the nose with the weight in it, let the cockpit area slow down, and then deploy a parachute. But what would that prove?

Also, because of the airspeed indicator issues I listed above, readings in excess of mach 1 on the airspeed indicator were unreliable anyway.

=S=

Lunatic

[FLYBOYJ]

Originally Posted by RG_Lunatic

Breaking the sound barrier in a dive would not really count anyway. Anyone could have done it. Just build a bullet shaped metal basket and drop it from 30,000 feet and walla - you will break the sound barrier - then release part of the basket at the nose with the weight in it, let the cockpit area slow down, and then deploy a parachute. But what would that prove?

Also, because of the airspeed indicator issues I listed above, readings in excess of mach 1 on the airspeed indicator were unreliable anyway.

=S=

Lunatic

I disagree with your statement about those early airspeed indicators. I worked on privately owned F-86s and Hawker Hunters and the pitot static systems were very similar and although they did produce errors close to mach, the errors were usually too slow of an airspeed while getting close to trans-sonic numbers. When we flew the Hunter, we really had to watch it because once it became trans sonic, it really wanted to "pop through." The owner of the aircraft would of gotten into big trouble for exceeding mach 1 in civilian airspace. But as far as Welch, I believe his feat was still noteworthy because...

1. There were witnesses to the fact. (Sonic Booms heard across the Antelope Valley).
2. Even though it was in a dive, it was still in an aircraft that took off and landed with a human pilot manipulating the controls, under its own power.

3. When pulling out of the dive, he was super sonic straight and level. Weather it's felt this feat is diminished because Welch did it in a dive is of ones opinion, but he must of hit a nerve with the Air Force as they were willing to at least temporarily cover the whole thing up!

Later in the same month, Welch repeated the same flight profile while being tracked from the ground using ground telemetry equipment. Although this equipment by today's standards is quite primitive, it was still pretty accurate and showed that the XF-86 did exceed mach 1. Additionally, it also showed only small errors within the airspeed indicator installed on the aircraft.

[delcyros]

I do not question the inaccuracy of the airspeed indicators (that´s why IAS and not TAS). But I believe these flights came really close to Mach speed or even break Mach 1 (IAS wasn´t the only evidence) if it could be confirmed from independent sources. And I agree with RG that level flight should be very important for this question (otherwise we should count some Me-262 dives which ended fatal for their pilots, too). With this in mind we are back on M.52, DFS 346 and X-1. What do you think? Estimate normal (war time) development time. My choice would be the M.52 (with more powerful engines) or maybe the DFS-346 in mid 1946.

[cheddar cheese]

www.luftarchiv.de quotes the estimated speed for the DFS-346 at over 2200kmh

[FLYBOYJ]

If it was able to be documented, early encounters with Trans sonic and super sonic flight should be counted, the problem is when first encountered few lived to tell about it.

One thing that many of these early reports had in common was the reporting of the nose dipping, commonly called super sonic dip. This was common on many 1st generation jet aircraft when exceeding the speed of sound. The nose would dip, there would be a loss of elevator effectiveness, then everything would "straighten out." This was mentioned in some of the ME-262 pilot reports, both by German and American pilots. The only way you're going to experience super sonic dip is to go super sonic, or pretty darn close to it!

[delcyros]

I disagree. The nose dip of the Me-262 occurs at speeds beyond Mach 0.86 because of the shifted center of weight (thanks to transsonic airflow on the upperside of the wing). This could be misunderstood as an supersonic dip (which could occur on 0 and 1st generation jets, also). However their is another point which implies that they really hit Mach: The controlls. Between Mach 0.88 (0.86 because of the dip) and Mach 1.0 you loose controll of the elevators (Me-262 A-1). But controlls have been regained after considerable acceleration in a dive (at full throttle in case of Mutke and US pilots). Wind tunnel testings confirms that controlls come back into effect after exceeding Mach 1 (which is confirmed by US pilots, also). The problem was that the test pilots tried to close the speed slowly in a dive (which implies really huge stress to the airframe), while some pilots accidently (Mutke) and in a rapid way accelerated. I still wonder if the airframe of the Me-262 can contain this stress (I really doubt) or is more probable to disintegrate.

[DerAdlerIstGelandet]

Interesting stuff.

[FLYBOYJ]

Originally Posted by delcyros

I disagree. The nose dip of the Me-262 occurs at speeds beyond Mach 0.86 because of the shifted center of weight (thanks to transsonic airflow on the upperside of the wing). This could be misunderstood as an supersonic dip (which could occur on 0 and 1st generation jets, also). However their is another point which implies that they really hit Mach: The controlls. Between Mach 0.88 (0.86 because of the dip) and Mach 1.0 you loose controll of the elevators (Me-262 A-1). But controlls have been regained after considerable acceleration in a dive (at full throttle in case of Mutke and US pilots). Wind tunnel testings confirms that controlls come back into effect after exceeding Mach 1 (which is confirmed by US pilots, also). The problem was that the test pilots tried to close the speed slowly in a dive (which implies really huge stress to the airframe), while some pilots accidently (Mutke) and in a rapid way accelerated. I still wonder if the airframe of the Me-262 can contain this stress (I really doubt) or is more probable to disintegrate.

Interesting - I flew at high mach numbers in a T-33 without tip tanks and I could tell you I thought the wings were going to shake off, the elevators seemed to buzz as well. The only other aircraft I flew in that approached and exceeded mach 1 was an F-4 - you felt nothing, just saw a slight jump in the airpseed indicator and mach meter, but that's another story!

[Nonskimmer]

Sounds like you've been around a bit alright, FLYBOYJ.