A variable cycle engine (VCE), also referred to as adaptive cycle engine (ACE), is an aircraft jet engine that is designed to operate efficiently under mixed flight conditions, such as subsonic, transonic and supersonic.
An advanced technology engine is a turbine engine that allows different turbines to spin at different, individually optimum speeds, instead of at one speed for all.[1] It emerged on larger airplanes, before finding other applications.
The next generation of supersonic transport (SST) may require some form of VCE. To reduce aircraft drag at supercruise, SST engines require a high specific thrust (net thrust/airflow) to minimize the powerplant's cross-sectional area. This implies a high jet velocity supersonic cruise and at take-off, which makes the aircraft noisy.
- ^ Wragg, David W. (1973). A Dictionary of Aviation (first ed.). Osprey. p. 4. ISBN 9780850451634.