Advanced Concepts

V/STOL (Vertical/Short Takeoff and Landing)

There are several ways to go straight up and end up flying, though the means of doing so is usually much heavier and less economical than doing one or the other exclusively. The Harrier and the Osprey (both, incidentally, named for birds of prey) are really the first generation of operational systems for VTOL. There will be others. A system is planned for the upcoming Joint Strike Fighter which will likely have a turbofan/shaft engine, driving another fan part-time to generate lift thrust.


The propfan bridges the gap between the turboprop and turbofan. Turbines power large, short span, wide chord fans without a duct around them. Performance is somewhere between a turboprop and a turbofan. As yet, the propfan's economy has yet to outweigh the noise problems and lower operating speed.

Advanced Turbofan Concepts

Ramjets : Information Page