This is the engine used in the V-1 Buzz Bomb. The 'V' in the V-1 stood for Vengeance weapon. The V-1 is considered to be the world's first cruise missle, and was used by Germany against London as a kind of terror weapon.
As the Londoners during the war can attest, the V-1 makes a very distinctive sound. Click on the play button below to experience that!
The pulse jet generated 500lbs of thrust, and could propel the V-1 at over 400mph. Using a counter and a propeller in the nose of the V-1 to determine distance travelled, the engine would cut out once the range has been reached, and the V-1 bomb would enter a steep dive and explode on impact.
Londoners therefore learnt to go about their daily business even when they heard the buzz bomb overhead. Only when the sound cut out would they take cover!
Kind of odd to just show the engine without the whole V-1, so here's a shot of the American V-1 version (didn't know they made one did you?) from the Smithsonian Udvar Hazy National Air and Space Museum. The American flying bomb was copied from salvaged V-1 parts, and was designated the JB-2, nicknamed 'Wendover Wille'. Although developed and built, it was not used in combat.