A thrust reverser for an aircraft propulsion unit, of the type having a mobile cowl able to move between a closed position that allows the propulsion unit to generate thrust and an open position that allows the propulsion unit to generate a reverse-thrust for slowing the aircraft. The reverser includes braking elements such as a slot and a peg respectively integral with a fixed part of the reverser and with the mobile cowl. These braking elements are configured to cooperate with one another by sliding, with friction, when the mobile cowl effects an overtravel, beyond the open position, so as to generate a braking force that opposes this movement. In one preferred embodiment, the slot for this purpose includes a restriction in section along the direction of travel of the mobile cowl.

A limit ring for use in a pump arrangement includes a cylindrical body positioned about a central longitudinal axis, a first end and an opposite second end. A central passage is defined through the cylindrical body and is centered about, and extends, along the longitudinal axis between the first end and the second end. The central passage has a circular cross section when viewed along the longitudinal axis. The limit ring further includes a number of channels defined in the cylindrical body radially outward from the central passage, each channel extending between the first end and the second end of the cylindrical body.

A compressor system for a turbo machine is provided. The turbo machine includes a low-pressure shaft coupled to a low-pressure turbine and a high-pressure shaft coupled to a high-pressure turbine. The high-pressure shaft and the low-pressure shaft are rotatable about a central rotational axis. The compressor system includes a fan driven by the low-pressure turbine via the low-pressure shaft, a booster compressor and a gear unit. The low-pressure shaft is coupled to a first input member of the gear unit. The high-pressure shaft is coupled to a second input member of the gear unit. An intermediate rotor is coupled to an output member of the gear unit. The intermediate rotor includes rotatable elements of the booster compressor and an electric motor-generator. The intermediate rotor is driven by the low-pressure shaft and the high-pressure shaft.

An in-line propeller gearbox of a turboprop gas turbine engine includes an epicyclic gearing arrangement that has a sun gear, a ring gear and at least one planet gear disposed between and meshing with both the sun gear and the ring gear. The propeller gearbox includes a disk brake that can be operated to slow down or stop altogether the rotation of the propeller. The disk brake has an axially extending shaft having at one end a disk and at the opposite end a gear having teeth that engage with one of the gears in the epicyclic gearing arrangement. The disk brake includes a hydraulic caliper or an electric caliper that can be actuated to slow down rotation of the disk to an eventual full stop and to hold the disk at full stop to thereby stop rotation of the propeller.

The present disclosure relates to a method of controlling the braking of an aircraft equipped with a landing gear bearing braked wheels, the aircraft being propelled by jet engines and equipped with a thrust reversal system, the method involving the steps of estimating the grip/adhesion of the braked wheels and activating the thrust-reversal system or modulating the reverse-thrust generated by the thrust-reversal system if this system is already activated, based on the estimated grip/adhesion.

This disclosure includes anti-reverse rotation apparatuses, rotors for use therein, and related methods. Some apparatuses include a stator defining an interior volume and one or more arcuate contact surfaces within the interior volume, and a rotor rotatably coupled to the stator and at least partially disposed within the interior volume, the rotor having a hub, two or more shoes, each pivotally coupled to the hub and extending between a first end and a second end that is farther from the hub than is the first end, wherein each of the shoes is rotatable relative to the hub between: (a) a first position in which the second end of the shoe contacts at least one of the arcuate contact surface(s) of the stator; and (b) a second position in which the second end of the shoe does not contact the arcuate contact surface(s) of the stator.

A gas turbine engine according to an exemplary aspect of the present disclosure includes, among other things, a fan and a braking system. The braking system is configured to selectively engage the fan during ground windmilling to apply a first level of braking to slow rotation of the fan. Further, when the rotation of the fan sufficiently slows, the braking system is further configured to apply a second level of braking more restrictive than the first level of braking.

A first gear system includes a first sun gear, a first ring gear, first intermediate gears and a first carrier. The first intermediate gears are between and meshed with the first sun gear and the first ring gear. Each first intermediate gear is rotatably mounted to the first carrier. A second gear system includes a second sun gear, a second ring gear, second intermediate gears and a second carrier. The second ring gear is coupled to the first carrier. The second intermediate gears are between and meshed with the second sun gear and the second ring gear. Each second intermediate gear is rotatably mounted to the second carrier. A first propulsor rotor is coupled to the first carrier. A rotating structure is coupled to the first ring gear and includes a turbine rotor. The rotating structure is configured to drive rotation of the first propulsor rotor through the geartrain.

A toothed coupling mechanism for an assembly of rotating elements of an aircraft gas turbine engine includes a pair of coupling halves having an axial toothed coupling interface therebetween. Each coupling half has a plurality of splined teeth inter-engaged about an axis for transmitting torque therebetween. A protrusion is located on one of the splined teeth of one of the coupling halves. A splined tooth of the other coupling half comes into contact with the protrusion in a situation of uncoupling of said coupling halves.

This disclosure includes anti-reverse rotation apparatuses, rotors for use therein, and related methods. Some apparatuses include a stator defining an interior volume and one or more arcuate contact surfaces within the interior volume, and a rotor rotatably coupled to the stator and at least partially disposed within the interior volume, the rotor having a hub, two or more shoes, each pivotally coupled to the hub and extending between a first end and a second end that is farther from the hub than is the first end, wherein each of the shoes is rotatable relative to the hub between: (a) a first position in which the second end of the shoe contacts at least one of the arcuate contact surface(s) of the stator; and (b) a second position in which the second end of the shoe does not contact the arcuate contact surface(s) of the stator.