In 1976 McDonnell Douglas received a letter from two dozen fire departments asking for a solution to fighting fires and rescuing people from burning hi-rise structures.

The resulting "Flying Fire Engine" was a 7x8 foot rescue platform that hung by a 500 to 1000 foot cable from an overhead helicopter. It had a small engine that powered thruster nozzles so the SMS could be moved horizontally. It could hold three firemen and 16 additional people.

Several demonstrations were held in 1978 but there were no sales.