little things...

 The picture above depicts a Hawker Tempest of the RNZAF. Below is the cover of a biography of USAF  test pilot Frank Kendall "Pete" Everest at one time the fastest man alive in the Bell X-2 at 1,900mph.

The Tempest was derived from the Hawker Typhoon which upon introduction was found to have a violent and sometimes fatal elevator flutter that could not be corrected.

The Bell X-2 was a swept wing version of the earlier rocket plane X-1 which had several in-flight explosions with loss of life and aircraft.

It was found that a few extra ounces of lead on the internal mass balance cured the Typhoons flutter problems and in the X-1 a ver patient investigation showed it was a combination of extremely volatile fuels on seals made of leather and impregnated with organic substances.

Happy endings inboth cases and the rocket motor trials paved the way for a whole new generation of synthetic o rings and supersonic aircraft .