Jul 18
Only prototype of the experimental Martin-Baker MB.5. With a counter-rotating propeller to cancel out torque and increase fuel efficiency, thrust, speed, and stability ad handling, in tested extremely well in performance, reliability and maintenance. Due to its basic wing design was significantly lost cheaper then the Spitfire.
The MB.5 was likely the most capable and successful experiment piston fighter of WWII but due to the arrival of jet technology, plus the only prototype crashed and caught on fire in a test flight leaving nothing behind.