TABLE OF CONTENTS Pilot training under abnormal conditions is an important application area of flight simulators. Extreme flight conditions can arise due to several reasons, for example flow separation at high angles of attack leading to stall (which we will address in the next section), due to asymmetric flight with large sideslip angles or due to control surface malfunctions leading to partial loss of control power. Modeling of aircraft behavior under such extreme conditions is complex and validation from flight tests particularly difficult because such configurations are difficult to fly and are safety critical involving some risk. Here, we consider the specific case of roll-spoiler hardover, tested on a Dornier 328 for the landing configuration of 32 deg. flaps. Starting from a horizontal level flight at an altitude of 8700 ft and 115 kts true airspeed (roughly 100 kts CAS), trim angle of attack of about 2.5 deg. with extended landing gear, the roll spoilers are drawn out on the left wing to the hardover limit of 75 deg. and mechanically held fixed. Under normal operating conditions the roll spoilers are coupled to the ailerons; they are deflected from 0 to 45 deg. linearly for aileron deflections between 3 and 25 deg.; for aileron deflections less than 3 deg. the roll spoilers are not active.
As common to the general procedure followed in the aerodynamic model development, first we simulate the aircraft response to flight maneuver inputs using a database developed from flight maneuvers under normal operating conditions,...
