Nose landing gear arrangements for aircrafts, aircrafts including such nose landing gear arrangements, and methods for making such nose landing gear arrangements are provided. In one example, a nose landing gear arrangement includes a wheel assembly and a main strut. The main strut is operatively coupled to the wheel assembly and is configured to move between an extended position and a retracted position. The main strut in the extended position extends outside of the fuselage substantially along a generally vertical plane to position the wheel assembly for takeoff and/or landing of the aircraft. The main strut in the retracted position is disposed inside the fuselage. A flexible sheet is disposed adjacent to the main strut and is configured such that when the main strut is in the extended position the flexible sheet is positioned substantially around the main strut.

A differential pressure sensor system for use in an aircraft comprises a differential pressure sensor for determining a differential pressure between a pressurizable aircraft cabin and an aircraft environment, the differential pressure sensor having a first port connectable to the pressurizable aircraft cabin via a first line and a second port connectable to the aircraft environment via a second line. A shut-off device of the differential pressure sensor system is arranged in the second line which is switchable between an open position in which it opens the second line, such that a pressure prevailing in the aircraft environment acts on the second port of the differential pressure sensor, and a shut-off position in which it closes the second line, such that the second port of the differential pressure sensor is shut off from the pressure prevailing in the aircraft environment.

A method of warning of early rotation of an aircraft during takeoff is disclosed. An improvement in aircraft performance and passenger comfort can be realised by monitoring for signs of early rotation and warning the pilot of such. By detecting when rotation has been commanded by the pilot, and the aircraft nose has started to lift off the ground, when the speed of the aircraft is below a threshold, early rotation can be determined and an auditory warning can mitigate the impact of that on aircraft performance.

A system for landing a mobile platform, such as an Unmanned Aerial Vehicle (“UAV”) and methods for making and using the same. The system can land the UAV by applying a magnetic levitation force upon the UAV and adjusting the applied magnetic levitation force. The system can initiate a landing process to a designated docking station and can guide the UAV to an adjacency of the designated docking station. Once the UAV has entered the adjacency, the magnetic levitation forces can take control of the landing process. During the landing process, certain magnetic sensitive devices installed on the UAV and/or on the designated docking station can be protected by turning them off or by shielding them. The system overcomes disadvantages of currently-available landing systems by restricting a size and weight of the landing arrangements, as well as, avoiding potential damage to the UAV and the designated docking station.

An unmanned aerial vehicle according to certain embodiments generally includes a chassis, a power supply mounted to the chassis, a control system operable to receive power from the power supply, at least one rotor operable to generate lift under control of the control system, and a winch mounted to the chassis. The winch includes a reel and a motor. The reel has a line wound thereon, the line having a free end. The reel includes a circumferential channel in which a wound portion of the line is wound onto the reel. The circumferential channel includes an inner portion, an outer portion, and a passage connecting the inner portion and the outer portion. The motor is operable to rotate the reel under control of the control system to thereby cause the line to wind onto and off of the reel, thereby causing the free end of the line to raise and lower.

A noise abatement system for an aircraft landing gear is provided. The system may have a retention member and a covering member. In this regard, the system may be configured to block the airflow through a structural void to abate noise. Moreover, the system may be shaped to diminish aerodynamic drag.

An unmanned aerial vehicle according to certain embodiments generally includes a chassis, a power supply mounted to the chassis, a control system operable to receive power from the power supply, at least one rotor operable to generate lift under control of the control system, and a motor operable to lower a free end of a line. The free end of the line is operable to engage a parcel to be delivered by the unmanned aerial vehicle. The control system is configured to operate the motor to cause the free end of the line to accelerate toward a delivery surface as the free end of the line passes through a first portion of a distance between the unmanned aerial vehicle and the delivery surface, and to decelerate as the free end of the line passes through a lower portion of the distance.

A sensor (1) comprising a casing (2) delimiting an internal volume (3) and having a passage (31) between the internal volume and a first external zone (Z1) external to the casing; a moving part (4) moveable inside the internal volume (3); detector (5) for detecting a movement of the moving part (4) comprising a detection portion (51) extending in the passage (31) and having a groove (52) open to the outside of the detection portion (51), the groove (52) extending between the first external zone (Z1) external to the casing and the internal volume (3) internal to the casing. The sensor (1) comprises first sealing structure (14) positioned around the detection portion (51) inside the passage (31), the first sealing structure (14) being arranged in such a way as to prevent fluid from passing between the internal volume (3) and the first external zone (Z1) via the groove (52).

An aircraft spring assembly includes a helical spring having a hollow core. A polymer damping member is confined within the core and is narrower than the internal spring diameter so as to be free to move along the core.

A tail skid shock absorber including an outer shock absorber canister, a crushable indicator cartridge disposed within the outer shock absorber canister, and an indicator rod coupled to the crushable indicator cartridge so as to move with a portion of the crushable indicator cartridge as a unit.