Related Clues:

• Simple propulsion unit
• Aircraft engine
• Type of plane
• Aviator's craft, perhaps
• Fast plane engine
• Powerful engine
• Engine using a stream of compressed air
• Powerful type of engine
• Large airplane engine
• Missile engine
• Certain aircraft engine
• Engine for missiles
• It's plain, by the sound of it, that it's sheepish not to have any prop
• The black sheep of the family engine?
• It moves so quickly the job overturned in utter confusion