blown flap


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blown flap

blown flap
A flap over which air is discharged to prevent boundary-layer separation and to improve the performance of the flap. Air is blown over the upper surface of the flap only. The efficiency of the system depends on the quantum and the speed of blown air.
References in periodicals archive ?
The YC-15 introduced a number of innovative features, such as externally blown flaps, which used double-slotted flaps to direct part of the jet exhaust downwards, while the rest of the exhaust passed through and downward over the flaps, introducing the Coanda effect.
This wide speed range implies the use of jet lift for stol, as earlier explored through upper surface blowing (Boeing XC-14) and externally blown flaps (McDonnell XC-15).
Northrop Grumman is proposing a B-2-like configuration with blown flaps and no vertical tail.