Question:

Could a P38 break sound barrier in full power dive?

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I have heard stories from WW2 pilots were they claim to have broken the sound barrier in a full power dive in a p38. I know there was a loss of controll around .90 mach so did they mistake this for the sound barrier or did they break it any opinions?

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  1. Not with a pilot that lived. Even in a dive it might make 550-575 mph max. Still short of supersonic.


  2. No, the aircraft could not break the should barrier, but the propeller could come very close.

    A propeller's performance suffers as the blade speed exceeds the speed of sound. As the relative air speed at the blade is rotation speed plus axial speed, a propeller blade tip will reach sonic speed sometime before the rest of the aircraft (with a theoretical blade the maximum aircraft speed is about 845 km/h (Mach 0.7) at sea-level, in reality it is rather lower). When a blade tip becomes supersonic, drag and torque resistance increase suddenly and shock waves form creating a sharp increase in noise. Aircraft with conventional propellers, therefore, do not usually fly faster than Mach 0.6.

  3. The problem with this particular scenario is that it is possible  to take the aircraft to its service ceiling,  point the nose straight down, and apply full power. The aircraft will quickly increase in speed, and, at some point, break apart. The engines being very heavy will continue down and acelerated further by gravity and will hit the earth at a very high rate of speed. The rest of the aircraft will follow thereafter. Some lighter parts may not arrive for several minutes, depending on the height of break-up. If you wish to consider that this is breaking the sound barrier, then it is up to you.

    The problem with breaking the sound barrier is that it IS A BARRIER. If the aircraft is not configured for it, it does not have a good chance to survive the encounter.

    Regards,

    Dan

  4. Neither was the P-38 designed for supersonic flight nor could she achieve it. Many phases of high speed flight generated unexplained effects which were construed as going through the sound barrier.

  5. no way dude a p38 could never do that

  6. The P-38 was never supersonic. It had a deadly high speed controllability problem that could be blamed on aero-elastic deflection of the elevator system. As in some other high performance WWII planes, the stabilizer deflected causing reverse control input in the plane. Pull on the stick and the nose would tuck down. This problem was solved by Chuck Yeager and his sidekick pilot/engineer on the Bell X-1.

  7. Not a chance !

  8. "Breaking the sound barrier" was a popular rumor during and right after WW2, as aviation technology approached the actual breakthrough in 1947.

    Lots of pilots claimed to have "broken the sound barrier" without really knowing what that means.  In fact, one can hardly imagine an airplane less suited for supersonic flight than the P-38.   But in fact no airplane exceeded the speed of sound until the Bell X-1 in 1947.

  9. perhaps pre-trans sonic.

    One thing IS for certain, something affected their flight characteristics in a power dive and was only solved by adding an air brake/flap.

  10. If the plane could go be in that dive at it's max dive speed at the time it's at it's max ceiling then maybe haha...

    are we saying this 38 still has it's wings in one peice? haha

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