2 ms·

I think that’s a ramjet.

• Animats 7y ago
  Right. A few ramjet aircraft and missiles have been built, but since you have to have another propulsion system to get up to ramming speed, it's only useful for special-purpose craft. The SR-71 engine was effectively a ramjet in some modes. It started up as a turbojet, but at full speed, it was running on ramjet type compression and the fans weren't adding any value. Managing the shock waves and turbulence at the intake end was a huge problem.