first man to break the sound barrier

[nimrod.michaeli]

wiki says that george welch broke the speed of soud as it says

and for allegedly being the first pilot to break the 'sound barrier' (two weeks before Chuck Yeager) in his prototype XP-86 Sabre.

so who broke the sound barrier first yeager or welch?

 

[gumbyk]

Computational tests carried out by Professor Otto Wagner of the München Technical University in 1999 suggest the Me 262 was capable of supersonic flight during steep dives. Recovering from the dive and the resumption of severe buffeting once subsonic flight was resumed would have been very likely to damage the craft terminally.

On page 13 of the "Me 262 A-1 Pilot's Handbook" issued by Headquarters Air Materiel Command, Wright Field, Dayton, Ohio as Report No. F-SU-1111-ND on January 10, 1946:
"Speeds of 950 km/h (590 mph) are reported to have been attained in a shallow dive 20° to 30° from the horizontal. No vertical dives were made. At speeds of 950 to 1,000 km/h (590 to 620 mph) the air flow around the aircraft reaches the speed of sound, and it is reported that the control surfaces no longer affect the direction of flight. The results vary with different airplanes: some wing over and dive while others dive gradually. It is also reported that once the speed of sound is exceeded, this condition disappears and normal control is restored."
The comments about restoration of flight control and cessation of buffeting above Mach 1 are very significant in a 1946 document.

In his book Me-163, former Me-163 pilot Mano Ziegler claims that his friend, test pilot Heini Dittmar, broke the sound barrier when steep-diving the rocket plane and that several on the ground heard the sonic bangs. Heini Dittmar had been accurately and officially recorded at 1,004.5 km/h (623.8 mph) in level flight on October 2, 1941 in the prototype Me163a V4. He reached this speed at less than full throttle as he was concerned by the transonic buffeting. The craft's Walter RII-203 rocket engine produced 7.34 kN (750 kgp / 1,650 lbf) thrust. The flight was made after a drop launch from a carrier plane to conserve fuel, a record that was kept secret till war's end. The craft's potential performance in a powered dive is unknown but the production version of the rocket plane had an even more powerful engine. Ziegler claims that on July 6, 1944, Heini Dittmar flying a production comet Me 163BV18 VA + SP was measured travelling at a speed of 1,130 km/h. Similar claims for the Spitfire and other propeller aircraft are more suspect. It is now known that traditional airspeed gauges using a pitot tubePitot tube
A Pitot tube is a pressure measurement instrument used to measure fluid flow velocity. The Pitot tube was invented by France engineer Henri Pitot in the early 1700s, and was modified to its modern form in the mid 1800s by French scientist Henry Darcy....
give inaccurately high readings in the transonic, apparently due to shock waves interacting with the tube or the static source. This led to problems then known as "Mach jump".

Sound barrier: Facts, Discussion Forum, and Encyclopedia Article

From this, it looks like the F86 could have broken the sound barrier, but, like any record, it has to be properly recorded to be oficially "broken"

 

[Marcel]

AFAIK the Sabre couldn't break the sound barrier in level flight. (note level) Chuck yeager was the first to do so in the Bell X-1.

 

[Gnomey]

Yep, Marcel has it. Yeager was the first to do it in level flight. Welch possibly broke it first although in a dive not level flight.

 

[Soren]

The F-86 could regularly did break the soundbarrier in dives, and according to research the Me-262 was capable of it as-well although it was extremely dangerous. So as to wether the Me-262 was first, maybe, maybe not. Some also suggest that the Me-163 was the first a/c to break the soundbarrier, and again it might and it might not have.

 

[gumbyk]

But, as Marcel put it, Yeager was the first to do it in level flight, all of the other aircraft had to dive to do it.

From the pilots descriptions, I would be of the opinion that the Me 262 did go supersonic in a dive.

So, I guess who "broke the sound barrier" depends on whether you will accept it being done in a dive, or whether you want to stick level flight. I kind of think that it has to be in level flight to be considered.

 

[TheMustangRider]

There are also claims that P-47 pilots managed to go supersonic in a dive and even a Spitfire pilot if I remember correctly.

 

[davparlr]

I am sure the Bell X-1 was first properly intrumented supersonic flight. All others are claims are claims, correct or not, hard to prove. I doubt that any propeller driven aircraft went supersonic.

Say, whats with the new format and small print. Tough on an old codger!

 

[Jabberwocky]

There are also claims that P-47 pilots managed to go supersonic in a dive and even a Spitfire pilot if I remember correctly.

I don't think that there has ever been any suggestion that the Spitfire went supersonic.

The airframe and wing simply wasn't built or designed for it, and propellers are a HUGE source of drag, especially as you approach trans-sonic speeds. You get mixed supersonic airflow and trans-sonic airflow mixing, which is BAD.

The fastest known dive speed for a Spitfire was .94 mach after a PR XIX pilot over Hong Kong lost consciousness at over 50,000 feet, although the actual speed is disputed as its calculated, not recorded.

The fastest recorded dive speed for a Spitfire was for a Mk XI (photo recon bird with no wing cannon) at .891 mach. Which involved shedding the prop during the dive.

Fastest speed for an armed Spitfire was for an FAA MK XVII, which recorded 0.88 mach in a dive. Again, prop sheared off the airframe.

 

[TheMustangRider]

As Davparlr pointed out those are only claims and very hard to prove in reality, prop driven fighters were ill-equiped to break the sound barrier.

 

[Soundbreaker Welch?]

I think Welch broke the sound barrier in a dive, but it's possible the Me-163 did as well, especially if they heard the Sonic booms when it dived. That's a good indicator that it went sonic. I can imagine the Me-163 doing that, it was built like a rocket.

 

[comiso90]

I think Welch broke the sound barrier in a dive, but it's possible the Me-163 did as well, especially if they heard the Sonic booms when it dived. That's a good indicator that it went sonic. I can imagine the Me-163 doing that, it was built like a rocket.

Except by the time it got to altitude... there wasn't much fuel left.

.

 

[nimrod.michaeli]

but it says the first one to break the sound barrier

it doesnt matter if he did it climbing, turning or diving

we can say that yeager was the first guy to break the sound barrier in a level flight

the other guy was the first one to break the sound barrier

 

[gumbyk]

Nimrod,
The problem is that none of the other aircraft had the instrumentation to be able to verify the claims. A standard airspeed indicator will not read correctly at slose to mach 1 airspeeds, so it becomes very difficult to verify.

Personally, I do think that others broke the sound barrier prior to the X-1, but an unverified/unsubstantiated claim cannot be taken as proof.

Just as there were (allegedly) others to fly prior to the Wright brothers, the verifiable proof isn't there, so the credit goes to the Wrights.

 

[Soren]

As already mentioned the F-86 regularly broke the soundbarrier in dives, with even a special demonstration team forming to do this for crowds of people to wittness.

As for the Me-163, there are wittness accounts who claim to have heard this a/c break the soundbarrier by hearing a sonic boom. IIRC these claims were made during the testing phase of the a/c where many level flight with full thrust were conducted.

 

[renrich]

I believe the second man was Marion Carl in an AC made by Douglas.

 

[Waynos]

re the Me 163. Is it possible to go supersonic in a plane that is wider than it is long? I am under the impression, admittedly just from stuff I have read, that this cannot be done?

 

[Graeme]

I believe the second man was Marion Carl in an AC made by Douglas.

Aerospaceweb.org | Ask Us - First Supersonic Pilots

First Supersonic Pilots
Order Name Nationality Organization Aircraft Date
1. Charles "Chuck" Yeager USA USAF X-1 #1 14 October 1947
2. James T. Fitzgerald, Jr. USA USAF X-1 #1 24 February 1948
3. Herbert "Herb" Hoover USA NACA X-1 #2 10 March 1948
4. Howard Lilly USA NACA X-1 #2 31 March 1948
5. George Welch USA North American Aviation XP-86 26 April 1948
6. Gustav "Gus" Lundquist USA USAF X-1 #1 29 April 1948
7. John Derry UK de Havilland D.H.108 VW120 9 September 1948
8. Eugene May USA Douglas Aircraft D-558-1 #1 29 September 1948
9. Robert "Bob" Champine USA NACA X-1 #2 2 December 1948
10. I. E. Fedorov USSR Soviet Air Force La-176 26 December 1948
11. Jackie "Jack" Ridley USA USAF X-1 #1 11 March 1949

 

[Soren]

re the Me 163. Is it possible to go supersonic in a plane that is wider than it is long? I am under the impression, admittedly just from stuff I have read, that this cannot be done?

It can be done and has been done many times. One example is the Northrop X-4.

 

[renrich]

My mistake, Carl set a world speed record in 1947 of 650 mph in a Douglas Skystreak.