Abstract: A system and method are provided for controlling turbine blade tip-to-static structure clearance in a gas turbine engine installed on an aircraft. Mode control data are processed to determine that a fuel-saving mode is enabled, and aircraft data are processed to determine that the aircraft gas turbine engine is generating a substantially constant thrust. The turbine blade tip-to-static structure clearance in the aircraft gas turbine engine is minimized upon determining that both the aircraft gas turbine engine is generating a substantially constant thrust and the fuel-saving mode is enabled. The turbine blade tip-to-static structure clearance in the aircraft gas turbine engine is then selectively increased to a predetermined clearance, and a change in aircraft gas turbine engine thrust is prevented until the predetermined clearance is achieved.

Abstract: Fault-tolerant lateral waypoint sequencing is provided for a system that includes at least a first flight management computer and a second flight management computer. A processing operation associated with lateral leg sequencing of an aircraft flight plan is implemented in the flight management computers. A determination is made in the first flight management computer as to whether the first flight management computer has received, within a predetermined period of time from when the first flight management computer implemented the processing operation, a notification from the second flight management computer that the second flight has also implemented the processing operation. An action is initiated in the first flight management computer when the first flight management computer has not received the notification from the second flight management computer within the predetermined period of time.

Abstract: A system and method are provided for controlling turbine blade tip-to-static structure clearance in a gas turbine engine installed on an aircraft. Mode control data are processed to determine that a fuel-saving mode is enabled, and aircraft data are processed to determine that the aircraft gas turbine engine is generating a substantially constant thrust. The turbine blade tip-to-static structure clearance in the aircraft gas turbine engine is minimized upon determining that both the aircraft gas turbine engine is generating a substantially constant thrust and the fuel-saving mode is enabled. The turbine blade tip-to-static structure clearance in the aircraft gas turbine engine is then selectively increased to a predetermined clearance, and a change in aircraft gas turbine engine thrust is prevented until the predetermined clearance is achieved.

Abstract: Fault-tolerant lateral waypoint sequencing is provided for a system that includes at least a first flight management computer and a second flight management computer. A processing operation associated with lateral leg sequencing of an aircraft flight plan is implemented in the flight management computers. A determination is made in the first flight management computer as to whether the first flight management computer has received, within a predetermined period of time from when the first flight management computer implemented the processing operation, a notification from the second flight management computer that the second flight has also implemented the processing operation. An action is initiated in the first flight management computer when the first flight management computer has not received the notification from the second flight management computer within the predetermined period of time.