| Abstract | Cycle calculations are presented for dual-operation powerplants, which use jet propulsion for cruising and rotors for hovering.
Turbojet and bypass powerplants are compared on the basis of specific power and fuel consumption during hovering, specific thrust, specific fuel consumption and power multiplication ratio while cruising, and ducting considerations.
It is shown that turbojet schemes should be run as hot as possible for hovering, but that the ducting is likely to have to operate at a high temperature. It is also shown that bypass schemes tend to be very bulky unless the bypass air is heated by combustion after it has been ducted to the lifting engines. |
|---|