Abstract: A system for fan stress tracking according to an example of the present disclosure includes, among other things, a computing device that has a memory and a processor. The computing device is operable to execute a data module and a comparison module. The data module is operable to access data corresponding to a sensed value of an engine inlet parameter, and is operable to access data corresponding to a fan stress fatigue ratio profile. The fan stress fatigue ratio profile is defined with respect to at least one fan blade. The comparison module is operable to associate the sensed value of the engine inlet parameter with a stress value according to the fan stress fatigue ratio profile. The comparison module is operable to determine whether the stress value meets at least one predetermined criterion.

Abstract: A method of thrust reversal operation according to an example of the present disclosure includes, among other things, permitting an increase in engine power when at least one criterion is not met and a thrust reverser is deployed, and denying the increase in engine power when the at least one criterion is met. A system for thrust reversal is also disclosed.

Abstract: A system for fan stress tracking according to an example of the present disclosure includes, among other things, a computing device that has a memory and a processor. The computing device is operable to execute a data module and a comparison module. The data module is operable to access data corresponding to a sensed value of an engine inlet parameter, and is operable to access data corresponding to a fan stress fatigue ratio profile. The fan stress fatigue ratio profile is defined with respect to at least one fan blade. The comparison module is operable to associate the sensed value of the engine inlet parameter with a stress value according to the fan stress fatigue ratio profile. The comparison module is operable to determine whether the stress value meets at least one predetermined criterion.

Abstract: A gas turbine engine comprises a compressor, a combustor, a turbine, and an electronic engine control system. The compressor, combustor, and turbine are arranged in flow series. The electronic engine control system is configured to generate a real-time estimate of compressor stall margin from an engine model, and command engine actuators to correct for the difference between the real time estimate of compressor stall margin and a required stall margin.

Abstract: A method of thrust reversal operation according to an example of the present disclosure includes, among other things, permitting an increase in engine power when at least one criterion is not met and a thrust reverser is deployed, and denying the increase in engine power when the at least one criterion is met. A system for thrust reversal is also disclosed.

Abstract: A gas turbine engine comprises a compressor, a combustor, a turbine, and an electronic engine control system. The compressor, combustor, and turbine are arranged in flow series. The electronic engine control system is configured to generate a real-time estimate of compressor stall margin from an engine model, and command engine actuators to correct for the difference between the real time estimate of compressor stall margin and a required stall margin.

Abstract: Time responsiveness to thrust demands for a fan jet engine of the type that includes twin spools and a variable inlet at the fan is enhanced by regulating air flow through the variable inlet while holding low pressure compressor speed constant. The thrust change is targeted as a function of power lever position which generates a low pressure compressor parameter as a function of engine and aircraft operating variables. This parameter is then utilized to control both the inlet variable vanes and fuel flow to 1) attain the targeted value and 2) return the engine to its steady state operating line after a given time interval.

Abstract: An active control system for use in gas turbine engines synchronizes exhaust nozzle area and burner fuel flow together with pas path variable engine parameters, such as fan variable vane and high compressor variable vane positions. As a result, extremely fast thrust transients are possible with optimized compression system stability, since fan and compressor rotor speeds are held high, allowing total engine power to be controlled by air flow and fuel flows directly.

Abstract: The time responsiveness and engine stability for an acceleration and deceleration engine transient is enhanced by a control mechanism that synchronously adjusts fuel flow and high pressure compressor vane position as a function of corrected low pressure compressor speed in a twin spool axial flow turbine power plant. The acceleration and deceleration mode is targeted by power lever position and the target is attained by adjusting the vane position at a constant high pressure compressor speed and returned to a fuel efficient and engine stable steady state operating line by concomittantly adjusting fuel flow and vane position.