SPACEPHOTOS

NASA's Dryden Flight Research Center, Edwards, California, is using a modified McDonnell-Douglas F-15B aircraft as a testbed for a variety of transonic flight experiments. The twin-engine, twin-tail aircraft is shown carrying a Dryden-designed Flight Test Fixture (FTF) upon which aerodynamic experiments are mounted. The F-15B flew several flights recently in support of an experiment to determine the precise location of of sonic shock wave development as air passes over an airfoil. The F-15B is currently being prepared for the Boundary Layer Heat Experiment, which will explore potential aerodynamic drag reduction from heating the turbulent portion of the air flow that passes over the fuselage of a large aircraft. The experiment also will measure the amount of electrical power required to achieve the expected heat-induced reduction in aerodynamic drag. Six thin electric resistance heaters well be mounted in the FTF, and both unheated and heated temperatures as well as surface air pressures will be measured.