“Most people imagine jet fuel as something extremely explosive.
In reality, it's designed to be surprisingly stable.
Commercial airliners use Jet-A, which is essentially highly refined kerosene — chemically much closer to diesel fuel than petrol.
One key property is its high flash point, around 38°C.
That means at normal temperatures it won't ignite easily from a spark or small flame.
This stability is intentional, reducing fire risk during refuelling, storage, and normal operations.
Jet engines don't rely on volatile fuel vapour like car engines. Instead, fuel is atomised into a fine mist and burned continuously inside the combustor, where airflow and pressure sustain the flame.
Piston aircraft use something very different.
Smaller aircraft engines typically run on Avgas 100LL(aviation gasoline).
Unlike Jet-A, this fuel is much more volatile, behaving more like automotive petrol.
It also still contains tetraethyl lead, which helps prevent engine knocking in high-compression piston aircraft engines.
Because of this, Avgas is one of the last leaded fuels still widely used anywhere in the world.
Bonus fact most people don't realise:
Jet fuel must remain usable at extremely low temperatures. At cruising altitude the outside air can be around -55°C, so Jet-A is formulated with a freeze point near -47°C to ensure it keeps flowing through the aircraft's fuel system.”
@GinieSiogenny via X
