An air vehicle configured to augment effective drag to change the rate of descent of the air vehicle in flight via propeller shaft rotation direction reversal, i.e., thrust reversal.

An aircraft comprising a fuselage and propelled by a turbine engine having two coaxial and contrarotating fans, the turbine engine comprising a power turbine having two contrarotating rotors, one of which drives a fan upstream from the turbine, the other a fan downstream from the turbine, each fan comprising a ring of blades, and the assembly of the fans and the power turbine being incorporated at the rear of the fuselage, in the extension of same. The aircraft comprises, for at least one of the fans, a device for blocking the rotation of the fan and a device configured to modify the pitch of the blades of the fan in such a way as to make it operate as a flow straightener with respect to the other fan.

Methods and systems for slowing down an aircraft having a propeller. The method comprises operating the propeller at a reference speed with the propeller blades in a first position, applying a load to the propeller to slow down a rotational speed of the propeller when the propeller is in a windmilling state or just before the propeller enters the windmilling state, adjusting the propeller blades to a second position in response to the load being applied, to increase the rotational speed of the propeller back towards the reference speed, and operating the propeller at the reference speed with the propeller blades in the second position.

A propeller for an aircraft having a fuselage and a pair of fixed wings includes a mounting member secured to at least one wing. At least one blade is rotatably connected to each mounting member and has an airfoil shape. The at least one blade is in a locked condition during take-off and landing of the aircraft extending parallel to a leading edge of the wing and in an unlocked, rotating condition during flight for propelling the aircraft.

An air vehicle configured to augment effective drag to change the rate of descent of the air vehicle in flight via propeller shaft rotation direction reversal, i.e., thrust reversal.

A propulsion system for an aircraft includes a propeller assembly, a controller, and a pump system. The propeller assembly includes a propeller and a power system, the power system including an electric motor and a motor converter. The controller is connected to the power system and configured to switch the power system into a power-off arrangement in response to a temperature of the motor converter being greater than a threshold temperature. The pump system includes a pump and a coolant circuit that cools the motor converter. The pump is coupled to the propeller and to the motor such that rotation of either drives the pump.

A rotor-regulation system includes a rotor that includes a plurality of rotor blades, a rotor mast operable to drive the rotor, and a rotor disc-brake system operable to modulate rotation of the rotor mast.

A motor assembly that includes a motor (102) having a rotatable shaft, a hub coupled to the rotatable shaft, the hub having a propeller indexer to receive a propeller (104), when the propeller is present, a sensor trigger rotatable with the shaft (100) and positioned at a propeller offset angle ?.sub.PROP from the propeller indexer, and a sensor coupled to the motor and positioned to detect the sensor trigger so that the propeller indexer may be positioned at the propeller offset angle ?.sub.PROP from the sensor through rotation of the shaft so that said sensor is proximate to the sensor trigger.

A propulsor brake lock system includes an aircraft propulsor, a reduction gear assembly, a brake shaft, and a brake assembly. The aircraft propulsor includes a propeller having a propeller input shaft coupled thereto. The reduction gear assembly includes at least an input gear and an output gear. The input gear and output gear are both rotatable with the propeller input shaft. The brake shaft is coupled to, and is rotatable with, the output gear. The brake assembly is coupled to the brake shaft and is moveable between a disengaged position, in which the brake shaft may rotate whenever the output gear rotates, and an engaged position, in which the brake shaft is prevented from rotating, thereby preventing rotation of the output gear, the input gear, and the propeller input shaft.

Systems and methods for delivering packages via aerial vehicles are disclosed. The system can comprise a label that includes a parachute to enable the packages to be dropped from the aerial vehicle, yet land at the package's destination without damage. The system can include a self-adhesive backing, a plurality of parachute cords, a parachute, and a breakaway cover. The parachute cords can include a shock absorber to reduce the shock on the package of the parachute opening. The parachute and/or the breakaway cover can include graphics to provide address, velocity, or spin information for the package. The parachute cords can include a harness to separate the cords and reduce tangling of the cords and spinning of the parachute canopy with respect to the package.