Vortex velocities were measured in the wakes of four configurations of a 0.61-m span model of a B-747 aircraft. The wakes were generated by towing the model underwater in a ship model basin. Tangential and axial velocity profiles were obtained with a scanning laser velocimeter as the wakes aged to 35 span lengths behind the model. A 45 deg deflection of two outboard flight spoilers with the model in the landing configuration resulted in a 36 percent reduction in wake maximum tangential velocity, altered velocity profiles, and erratic vortex trajectories. Deployment of the landing gear with the inboard flaps in the landing position and outboard flaps retracted had little effect on the flap vortices to 35 spans, but caused the wing tip vortices to have: (1) more diffuse velocity profiles; (2) a 27 percent reduction in maximum tangential velocity; and (3) a more rapid merger with the flap vortices. Wake vortex minimization by spoilers and landing gear; the variables include wake velocity profile, vortex trajectory, wing tip vortex formation, flap vortex formation, and lift coefficient; 9 figures and no tables.
Effects of Spoilers and Gear on B-747 Wake Vortex Velocities
1976
25 pages
Report
No indication
English
Aerodynamics , Aircraft , Aircraft wakes , Boeing 747 aircraft , Flow velocity , Vortices , Scale models , Flaps (Control surfaces) , Flow measurement , Landing gear , Laser applications , Velocity distribution , Aerodynamic coefficients , Flow distribution , Turbulence , Vortex breakdown , Vortex generators , Wakes
Evaluation of flight spoilers for vortex alleviation
AIAA | 1977
|Evaluation of flight spoilers for vortex alleviation
NTRS | 1977
|NTRS | 1991
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