A system for landing, comprising a vertical-take-off-and-landing (VTOL) unmanned air vehicle (UAV) having landing gear, wherein the landing gear is telescopic and comprises a sensor, and wherein the landing gear is compressed upon landing on a surface, and the compression causes a signal to be sent to a system that computes the slope of the ground surface using the length of the compressed landing gear and the attitude of the UAV. If the center of gravity falls within the support area, the legs are locked and the UAV power is turned off. If the center of gravity falls outside the support area, the UAV is forced to take off and find a safer landing spot.

A system for landing, comprising a vertical-take-off-and-landing (VTOL) unmanned air vehicle (UAV) having landing gear, wherein the landing gear is telescopic and comprises a sensor, and wherein the landing gear is compressed upon landing on a surface, and the compression causes a signal to be sent to a system that computes the slope of the ground surface using the length of the compressed landing gear and the attitude of the UAV. If the center of gravity falls within the support area, the legs are locked and the UAV power is turned off. If the center of gravity falls outside the support area, the UAV is forced to take off and find a safer landing spot.

An aircraft landing gear assembly (112) including a shock absorber strut (114), a bogie (120), a link assembly (124), and a movement detector (132). The shock absorber strut includes an upper and a lower telescoping parts (118, 116), the upper part being connectable to the airframe of an aircraft and the lower part being connected to the bogie such that the bogie may adopt different pitch angles. The link assembly extends between the upper and lower telescoping parts, such that relative movement between the upper and lower telescoping parts causes relative movement between parts of the link assembly. The movement detector is arranged to detect movement of the link assembly relative to the bogie. The movement detector detects movement by sensing a change in linear displacement of, or angle between, one or more members.

An aircraft includes a frame body that includes an attaching unit on an upper portion thereof, that is formed into a frame-shape structure, and that couples an object to a lower portion thereof, the attaching unit being configured to be capable of adjusting a position in an up-down direction of the attaching unit. A main body including a flying mechanism is positioned on an upper portion of the frame body. A control unit controls a position in the up-down direction of the attaching unit such that a flying posture of the object is controlled in accordance with a posture of the flying mechanism.

An aircraft includes a frame body that includes an attaching unit on an upper portion thereof, that is formed into a frame-shape structure, and that couples an object to a lower portion thereof, the attaching unit being configured to be capable of adjusting a position in an up-down direction of the attaching unit. A main body including a flying mechanism is positioned on an upper portion of the frame body. A control unit controls a position in the up-down direction of the attaching unit such that a flying posture of the object is controlled in accordance with a posture of the flying mechanism.

A landing gear system uplock arrangement (300, 500) including: a hook (310) defining a gap (314), wherein the hook is movable between a first position, at which the hook is for retaining a movable element (299, 499) of a landing gear system in the gap, and a second position, at which the hook is for permitting movement of the element into and out from the gap; a lock (320) that is changeable between a locked state, in which the lock prevents movement of the hook from the first position to the second position, and an unlocked state, in which the lock permits movement of the hook from the first position to the second position; and a sensor arrangement (330) for sensing whether the element is present in the gap.

A landing gear system uplock arrangement (300, 500) including: a hook (310) defining a gap (314), wherein the hook is movable between a first position, at which the hook is for retaining a movable element (299, 499) of a landing gear system in the gap, and a second position, at which the hook is for permitting movement of the element into and out from the gap; a lock (320) that is changeable between a locked state, in which the lock prevents movement of the hook from the first position to the second position, and an unlocked state, in which the lock permits movement of the hook from the first position to the second position; and a sensor arrangement (330) for sensing whether the element is present in the gap.

A method of determining whether a landing event of an aircraft is hard may comprise: receiving, by a controller via a stroke position sensor, a stroke profile as a function of time for a shock strut; receiving, by the controller via a gas pressure sensor, a gas pressure in a gas chamber of the shock strut; receiving, by the controller via a wheel speed sensor, a wheel speed of a tire in a landing gear assembly; calculating, by the controller, multiple time dependent functions based on the stroke profile of the shock strut, based on the gas pressure, a shock strut temperature, and the wheel speed; and comparing, by the controller, the multiple time dependent functions to respective predetermined thresholds to determine whether the landing event is hard.

Methods and apparatus for controlling landing gear retract braking are described. A controller is to determine an on-ground status of a wheel of a landing gear. The controller is to generate a control signal based on the on-ground status of the wheel. The control signal is to initiate a retract braking process for the wheel. The retract braking process is to decelerate the wheel from a first rate of rotation to a second rate of rotation less than the first rate of rotation.

Methods and apparatus for controlling landing gear retract braking are described. A controller is to determine an on-ground status of a wheel of a landing gear. The controller is to generate a control signal based on the on-ground status of the wheel. The control signal is to initiate a retract braking process for the wheel. The retract braking process is to decelerate the wheel from a first rate of rotation to a second rate of rotation less than the first rate of rotation.