A method according to certain embodiments generally involves operating a system including an unmanned aerial vehicle (UAV) and a base station. The base station includes a nest including an upper opening having an upper opening diameter and a lower opening having a lower opening diameter less than the upper opening diameter. The lower opening is accessible from within the base station. The method generally includes landing the UAV within the nest such that a portion of the UAV is accessible via the lower opening, releasably attaching a load to the UAV, and operating the UAV to deliver the load to a destination.

An aircraft tail skid energy absorption indicator including a crushable indicator cartridge disposed within the an outer shock absorber canister of the aircraft tail skid, 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, where the indicator rod extends through an aperture in a wall of the outer shock absorber canister, where the indicator rod includes at least one graduation that indicates an amount of remaining energy absorption of the aircraft tail skid energy absorption indicator.

An electrically powered STOL aircraft having dedicated motors energized to deploy movable landing gear driven to propel short takeoffs and to actively rotate downwardly to engage the runway surface as the aircraft approaches touchdown on landing. The front and rear landing gear, or both, may be powered and actuated in the landing process with braking to shorten the landing distance, each driven landing gear wheel having a dedicated electric motor and coaxial brake.

An electrically powered STOL aircraft having dedicated motors energized to deploy movable landing gear driven to propel short takeoffs and to actively rotate downwardly to engage the runway surface as the aircraft approaches touchdown on landing. The front and rear landing gear, or both, may be powered and actuated in the landing process with braking to shorten the landing distance, each driven landing gear wheel having a dedicated electric motor and coaxial brake. The landing gear modules are configured and controllable to differentially deploy downwardly so as to enable countersteering during taxi maneuvers and turns.

A landing assembly and method of landing an aircraft. The landing assembly includes a landing gear, a charging circuit, a sampling circuit and a processor. The charging circuit applies a charge to the landing gear and the sampling circuit measures a discharge rate of the electrical charge from the landing gear. The processor determines a contact between the landing gear and a surface from the discharge rate.

A system for shrinking landing gear includes a shock strut having a cylinder and a piston to be received by the cylinder. The system further includes a collar coupled to a brace linkage and the piston, a torque arm configured to resist rotation between the collar and the piston, and a shrink linkage coupled between the torque arm and the cylinder. The collar rotates relative to the cylinder in response to retraction of the landing gear. Rotation of the collar rotates the piston and the torque arm relative to the cylinder. The rotation of the collar relative to the cylinder forces, via the shrink linkage, the piston towards the aircraft attachment within the cylinder.

An aircraft undercarriage comprising a shock absorber further comprising first and second portions that are mounted to slide telescopically relative to each other and that can come into internal abutment in the event of the shock absorber being compressed, the undercarriage being fitted with a detector device for detecting the shock absorber coming into internal abutment, which comprises firstly a punch secured to the first portion of the shock absorber or to a portion of the undercarriage that does not slide relative to the first portion of the shock absorber, and secondly a sacrificial piece secured to the second portion of the shock absorber or to a portion of the undercarriage that does not slide relative to the second portion of the shock absorber, the punch and the sacrificial piece being arranged in such a manner that, in the event of the two portions of the shock absorber coming into internal abutment, the punch strikes the sacrificial piece so as to form an indentation therein.

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.

An unmanned aerial vehicle according to certain embodiments generally includes a chassis, a control system, and at least one rotor. The chassis includes a first battery compartment configured to receive sliding insertion of a first battery, and a second battery compartment configured to receive sliding insertion of a second battery. The control system is operable to receive power from the first battery and the second battery when the first battery is received in the first battery compartment and the second battery is received in the second battery compartment. The at least one rotor is operable to generate lift under control of the control system when both the first battery and the second battery are installed to the chassis. The control system is configured to remain at least partially active under power supplied by the first battery when the second battery is removed from the second battery compartment.

A method according to certain embodiments generally involves operating a system including an unmanned aerial vehicle (UAV) and a base station. The base station includes a nest including an upper opening having an upper opening diameter and a lower opening having a lower opening diameter less than the upper opening diameter. The lower opening is accessible from within the base station. The method generally includes landing the UAV within the nest such that a portion of the UAV is accessible via the lower opening, releasably attaching a load to the UAV, and operating the UAV to deliver the load to a destination.