What causes jet engine fuel to ignite?

Question

What causes jet engine fuel to ignite?

Answer 1

Bardic is right.

In fact it's a combination of the igniters and the compression within the engine, just like in a diesel. Jetfuel is very similar to diesel, if it wasn't for the low temperatures you could run a jet engine on diesel easily- as you can run a diesel on jetfuel without any problems.

Answer 2

I take it you mean in a jet engine. It's lit by "igniters", which are basically spark plugs, an electric spark does the trick. One the engine is running it's self-sustaining just like a blowlamp, gas ring etc. though the igniters are sometimes turned on in heavy rain etc in case the flame is put out.