The Alvis Leonides and Leonides Major were British piston aero-engines that found most use in helicopters Alvis (All-Wise) in Norse mythology was a dwarf. ...

Leonides

The Leonides was developed at the start of the Second World War. it was a nine-clyinder radial engine. Mushroom cloud from the nuclear explosion over Nagasaki rising 18 km into the air. ...

Leonides Major

The Major was a 14 cylinder, two row radial developed from the Leonides.

It was used on the Westland Whirlwind helicopter. There have been two Westland Whirlwind aircraft in Royal Air Force history. ...