Analysis of aircraft control strategies for microburst encounter

Penetration of a microburst-type windshear during takeoff or approach is an extreme harzard to aviation, but analysis has indicated that risks could be reduced by improved control strategies. Attenuation of flight-path response to microburst inputs by feedback control to elevator and to throttle was studied for a jet transport and for a general aviation aircraft using longitudinal equations of motion, root locus analysis, Bode plots of altitude response to wind inputs, and nonlinear numerical simulation. Response to several idealized microburst wind fields was studied for the approach and takeoff flight phases. Tight control of air-relative energy, pitch-up response to decreasing airspeed, increased phugoid-mode damping, and decreased phugoid natural frequency were shown to improve microburst penetration characteristics. Aircraft stall and throttle saturation were found to be limiting factors in an aircraft's ability to maintain flight path during a microburst encounter.