One element of Flight Research studies aircraft performance and flying qualities, addressing the influence of applied aerodynamics thereupon. Although undertaken from a fundamentally different precept to flight test, the practice of flight research follow the principles of flight test - flight research techniques tend to be based upon flight test experience, and their development and usage follows the 'build-up' principle. Perhaps because the objectives of aerodynamics flight research are highly defined, the reverse procedure might not be often used -namely, folding the benefits of flight research back into flight test practice. There might be benefit in doing so. NRC flight research into dynamic stall upon takeoff, and the flight research techniques applied thereto are presented and discussed, as a Case Study. The background to such flight research is the sporadic occurrences of operational and/or flight test incidents and accidents over many decades, involving abrupt wing stalling of jet transport aeroplanes near the ground, sometimes preceded by relatively high pitch rates, sometimes involving wing roughness, and often leading to wing drop and loss of control. Incidents and accidents of this nature have involved many Type Designs, ranging from the first to contemporary jet transports. In many, but not all, of the instances studied, the dynamic stalling involved coupled roll or roll/yaw characteristics (wing heaviness, abrupt wing drop, yaw, wing rock) and pitch instability, at times coupling with control surface deflections. Due to the significance of ground effect, pitch-ups on high speed taxi have proven to be one of a useful suite of flight research manoeuvres -not only to quantify aerodynamic effects, but for takeoff envelope safety clearance. In turn, the NRC has applied the high speed taxi pitch-up technique for First Flight takeoff safety clearance of fundamental aerodynamic re-configurations.
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