Robert M. Edholm - test pilot McDonnell - sound barrier?

[Leendert]

The gravestone of (Major) Robert M. Edholm (1917-1988) has the inscription 'First Man to Break the Sound Barrier in an Airplane'.(see https://nl.findagrave.com/memorial/1...obert-m-edholm)

Not to refute this accomplishment, when, where and in what airplane would this have happened given the general acceptance that Chuck Yeager was the first person to do so?

Edholm (O-391775) was with HQ Materiel Command at Wright Field, Ohio during WW 2 and after the war test pilot for McDonnell Aircraft, St. Louis (MO) in types as the F2H Banshee (1947), XF-88 Voodoo (1948) and F3H Demon (1951).

Any info to shed a light here is welcome, thanks.

Leendert

[Stig Jarlevik]

Being Chief Test Pilot with McDonnell, Edholm made the first flight in the XF-88 on 20 Oct 1948

The XF-88 is known to have exceeded Mach 1 in a dive (I have no date for that), but we can be
pretty certain that the first pilot who did that was Edholm.

While he was not the first one to fly past the "barrier", he certainly was among the first to do so.

Cheers
Stig

[twocee]

Stig,

In an article on the XF-88 in the July 1982 Aeroplane Monthly Bill Gunston wrote that on 12 May 1949 Edholm dove the aircraft from 41,000 ft. and reached a Mach number in the region of 1.17 to 1.19. He goes on to remark that there was not "the slightest buffet, trim change, flutter or yaw".

The XF-88 was an experimental fighter, not a special test aircraft like the Bell X-models.

[Stig Jarlevik]

Originally Posted by twocee

Stig,

In an article on the XF-88 in the July 1982 Aeroplane Monthly Bill Gunston wrote that on 12 May 1949 Edholm dove the aircraft from 41,000 ft. and reached a Mach number in the region of 1.17 to 1.19. He goes on to remark that there was not "the slightest buffet, trim change, flutter or yaw".

Thanks George
Should in fact have that article.....somewhere....

Cheers
Stig

[Leendert]

Thanks for info. It is my hunch here that 'airplane' as written on Edholm's grave is seen as opposite to Yeager's air-launched X-1 'rocket plane'.
Edholm in the XF-88 Voodoo therefore may indeed have been the first man to have broken the sound barrier after a conventional runway take-off.

Leendert