Top 5 Facts: Jet engines

1. Heavy-duty turbines
To generate electricity, some powerplants use 100-ton gas turbine engines fuelled by natural gas. Residual heat can be used to boil water for a secondary steam turbine.

2. Engine placement
Airframe manufacturers are testing out novel engine configurations – eg flush with the fuselage, or two in the rear with no separation – to boost thrust and decrease drag.

3. Hybrid rocket jet
UK company Reaction Engines Limited is developing the first-ever rocket plane with an ‘air-breathing’ jet engine at low altitude and a rocket mode to leap into orbit.

4. Jet-powered tank
The US Army’s M1 tank sports a gas turbine engine under the hood, providing enough thrust to go from 0-32 kilometres (0-20 miles) per hour in 7.2 seconds.

5. Jet cars
In the Sixties, some racers in the Indianapolis 500 drove cars combining a turboshaft helicopter engine with a four-wheel drive transmission. They were quickly outlawed.