Abstract: A method of automatically jettisoning cargo suspended from a suspension system coupled to an auto jettison system, includes receiving an initial load value from at least one attachment point of the suspension system, the receiving of the initial load value in response to attaching the cargo to the suspension system; receiving an instantaneous load value of the cargo suspended on an attachment point, the attachment point being coupled to the cargo; predicting a rate of change of the instantaneous load value at a predetermined future time period; combining the predicted rate of change of the instantaneous load value with the initial load value to create a predicted load value; comparing the predicted load value to a threshold value for the attachment point; and jettisoning the cargo from the attachment point if the predicted value is greater than the threshold value.

Abstract: A method of automatically jettisoning cargo suspended from a suspension system coupled to an auto jettison system, includes receiving an initial load value from at least one attachment point of the suspension system, the receiving of the initial load value in response to attaching the cargo to the suspension system; receiving an instantaneous load value of the cargo suspended on an attachment point, the attachment point being coupled to the cargo; predicting a rate of change of the instantaneous load value at a predetermined future time period; combining the predicted rate of change of the instantaneous load value with the initial load value to create a predicted load value; comparing the predicted load value to a threshold value for the attachment point; and jettisoning the cargo from the attachment point if the predicted value is greater than the threshold value.

Abstract: A helicopter flight control system (21) includes a model following control system architecture which automatically provides a coordinating yaw command signal to the helicopter tail rotor to coordinate helicopter flight during a banked turn. The control system processes information from a variety of helicopter sensors (31) in order to provide the coordinating yaw command signal on an output line (72) to the tail rotor (20) of the helicopter.

Abstract: A helicopter flight control system includes a model following control system architecture having provisions to compensate for Euler singularities which occur when the pitch attitude of the helicopter starts to approach ninety degrees. The control system processes information from a variety of helicopter sensors in order to provide the control commands to the helicopter main and tail rotors. The present invention synchronizes a sensed attitude signal, and a desired attitude signal as the pitch attitude of the helicopter approaches ninety degrees to compensate for the Euler singularities.

Abstract: The capability of compensating automatically for a failure in an actuator and the associated drive circuit is enhanced by providing a dual channel actuator, each channel having a drive coil and a position sensor tracking the position of the actuator output shaft. A separate circuit is provided for each actuator channel to detect drive loop failures and hydraulic failures. When the drive loop of one channel fails, it is disengaged, and the gain in the remaining drive loop is doubled to maintain authority. In an embodiment, the remaining drive loop cannot disengage when certain criteria, relating to the failure of associated actuators, are met. The invention is particularly useful for aerospace applications.

Abstract: An oscillatory-failure monitor (101) compares a parameter of a plurality of signals (A, B) within a tolerance (TOL) to determine agreement or disparity among the signals. Each discrete miscompare occurrence (i.e., singular disparity following full agreement) is counted by incrementing (27; 54) a counter (OSCCT; CNTR). The counter is decremented (32; 62) whenever the signals compare for a predetermined time interval (29; 47). An oscillatory-failure is declared when the counter increments to a threshold (28, 21; 57, 58, 60). Both digital (FIG. 1) and dedicated hardware (FIG. 4) embodiments are disclosed.

Abstract: A torque limiting altitude hold system for a helicopter engages torque limiting (56, 203) when excessive torque is anticipated (138, 202) as determined by the summation of present torque and torque rate times a reference value (126, 194) exceeds maximum torque with torque limiting engaged, altitude commands are faded out (42, 189) and torque commands are faded in (44, 190) and the collective command integrator is switched from altitude to torque (48, 54; 181, 185), torque limiting is ended in response to negative altitude commands or anticipated desired altitude signal (96, 150, 152; 205, 206); the anticipated desired altitude is determined by subtracting from the altitude error a time function of the altitude rate (84, 90; 193), torque limiting is not allowed to reengage for two seconds after disengaging (144, 204) nor within three seconds after reaching desired altitude during an automatic descent (146, 207), the system provides smooth transitions from altitude control to torque control, without oscillation