Month in the Patent Office

An automatic release device, more particularly for a brake parachute, consists of a part‐spherical body 1 housing a cylinder 8 and piston 11, to the rod 12 of which is coupled, by locking balls 25 in a socket 13, a plug member 14 with an eye 15 to which the parachute lines are attached. The device is normally retained in the position shown by liquid pressure supplied from an accumulator 33 to the right‐hand side of piston 11, through a pipe 32, past a lightly loaded non‐return valve 37, and through a second pipe 29 and ports 27 formed in the end of cylinder 8. In the event of the parachute opening inadvertently while the aircraft is moving at high speed, the pull transmitted to piston 11 generates a pressure in cylinder 8 sufficient to open a relief valve 36 to allow piston 11 and member 14 to move to the right, thus freeing balls 25 to allow dis‐engagement of member 14 from socket 13 and release of the parachute. The pilot may effect release at any time when there is a sufficient pull on member 14 to move piston 11 against the pressure generated by accumulator 33, by opening a solenoid valve 38. The body portion 1 is normally held by a ball catch 42 with its axis in alignment with the longitudinal axis of the aircraft, but the catch docs not prevent rotation of the member 1 under an oblique pull.