Here's some pretting interesting info on supersonic flight.
The concept of wings with subsonic sweep came to Jones in January 1945, and he eagerly discussed it with Air Force and NACA colleagues during the next
few weeks. Finally, he was confident enough to make a formal statement to the NACA chieftains. On 5 March 1945, he wrote to the NACA's director of
research, George W. Lewis. "I have recently made a theoretical analysis which indicates that a V-shaped wing traveling point foremost would be less
affected by compressibility than other planforms," he explained. "In fact, if the angle of the V is kept small relative to the Mach angle, the lift
and center of pressure remain the same at speeds both above and below the speed of sound."
So much for theory. Only testing would provide the data to make or break Jones's theory. Langley personnel went to work, fabricating two small models
to see what would happen. Technicians mounted the first model on the wing of a P-51 Mustang. The plane's pilot took off and climbed to a safe
altitude before nosing over into a high-speed dive towards the ground. In this attitude, the accelerated flow of air over the Mustang's wing was
supersonic, and the instrumented model on the plane's wing began to generate useful data. For wind tunnel tests, the second model was truly a
diminutive article, crafted of sheet steel by Jones and two other engineers. Langley's supersonic tunnel had a 9-inch throat, so the model had a
1.5-inch wingspan, in the shape of a delta. The promising test results, issued 11 May 1945, were released before Allied investigators in Europe had
the opportunity to interview German aerodynamicists on delta shapes and swept wing developments.
The F86 Sabre was the first swept-wing jet fighter to fly with the United States Air Force. It had very good performance for the time, going
supersonic in a shallow dive just a few weeks AFTER
Chuck Yeager became the first man to break the sound barrier, flying the rocket propelled
X1. Sabres were pitted against MiG15s during the Korean war; the MiG could outclimb the Sabre, but the Sabre was faster in a dive and had better
horizontal maneuverability. Overall, some people consider the MiG slightly superior to the Sabre, but because of better pilot training the Americans
achieved a better than 8-to-1 kill ratio against the communist pilots. Ironically, both aircraft were powered by the same jet engine, the British
However, it appears that yes it DID beat Yeager into supersonic flight.
The airspeed indicator wound up to about 405 mph, and seemed to get stuck there. Yet, there was no doubt that the XP-86 was still accelerating.
Everything felt normal, until passing below 30,000 feet where a tendency to roll needed some minor correction. George pushed the nose over a bit more.
Then, suddenly, the airspeed indicator jumped beyond 470 mph and continued to go up. Passing 25,000 feet, Welch eased back on the stick and pulled
back the throttle. Once again, there was a bit of wing roll and the airspeed indicator jumped back from 520 to 450 mph (520 mph indicated translates
to 720 mph true at this altitude, uncorrected).
Prior to heading back to North American to brief the engineers, George telephoned Millie Palmer. Excitedly, Millie related that a terribly loud
ba-boom had nearly blown her out of bed. The time was noted and it corresponded to George’s dive. “Pancho”, Millie related, “is really pissed.
You know how she feels about Yeager.” Apparently, Pancho claimed the boom was a result of mining operations going on 30 miles away to the north. Of
course, no one had previously heard any mining explosions, nor could that account for rattling windows only on the east facing side of the Fly Inn.
Welch chuckled and swore Millie to secrecy.
After briefing the engineering team at North American, Welch tracked down Ed Horkey. There were some “funny” instrument readings during the dive,
and George was looking for some answers.
Horkey guessed that Welch had run into a previously unknown Mach effect. Indeed he had. What Welch had observed was a phenomenon that would later be
called, “Mach jump”. Today, “Mach jump” is generally considered solid evidence of speeds in excess of Mach 1. Of course, on October 1, 1947,
no had ever seen it before.
It appears that the F-86 prototype DID break the sound barrier, however due to the politics involved it was covered up, until Chuck Yeager and the X-1
"officially" broke the sound barrier in October of 1947. I don't think we'll get much more proof than what I've found here. OFFICIALLY, it went
supersonic AFTER the X-1 did, however based on what they found during test flights, I would have to say that it ACTUALLY went supersonic before the
X-1 did. They were aware of the fact that the F-86 was potentially capable of supersonic flight, however were told not to do anything to prove that,
Chuck Yeager and the X-1 officially broke the sound barrier. They were informed by Stuart Symington, who was Secretary of the Air
Force. He didn't want any thunder stolen from their pet project, the X-1. Larry Bell, of Bell Aircraft had apparently learned that the XP-86 could
potentially break the sound barrier, and complained to the President that North American was trying to upstage their test flights. Politics does it
[edit on 11/27/2005 by Zaphod58]
[edit on 11/27/2005 by Zaphod58]