If you look closely at the top of the engine cowling of a V-1 “Buzz Bomb,” you will see a familiar but seemingly out-of-place object: a spark plug.
The V-1’s simple pulse-jet engine mixes fuel and air, but you need a third component to make a fire, or in this case, a controlled violent explosion. On the ground, that simple plug provided the spark.
Early studies showed that, under ideal conditions, the combustion cycle was self-sustaining after one initial addition of electric current. Secondary shock waves in the combustion chamber would reignite the next pulse and the V-1 was sent on its destructive aerial mission.