Abstract: A positioning and position maintaining device comprises a solenoid having an armature and an electromagnetic holder. The solenoid is arranged to effect positioning of an object upon translation of the armature and the electromagnetic holder is arranged to effect position maintaining in order to maintain the object in the position effected by the solenoid. An apparatus for aircraft autopilot and manual control feel-force control switching comprises an autopilot mechanism and the positioning and position maintaining device. The positioning and position maintaining device is arranged to engage the autopilot mechanism and maintain the engagement thereof. A method of switching between autopilot and manual control in an aircraft is also envisaged.

Abstract: Flight management systems can behave erratically when the distance measurements on which they are based are subject to value jumps because they liken these value jumps to movements of the aircraft performed at speeds exceeding the performance levels of the aircraft for which they were designed. To avoid this, the proposed flight management system uses a filter to spread the distance value jumps in time, over periods of the order of those needed for the aircraft to come through the distance differences that they represent. This filter replaces a value jump with a ramp making up the difference and corresponding to a movement that remains within the performance scope of the aircraft.

Abstract: The present invention relates to helicopter automatic piloting equipment. The automatic piloting device for helicopter acts on flight controls of the helicopter that are affected by mechanical play by means of a group of mechanically irreversible rams termed series rams with fast response and short stroke, placed in series on the flight controls. According to the invention, the device comprises at least one detector for detecting direction of variation of the displacement instructions of the series rams and a play compensator adding to the instruction, as a function of the latter's direction of variation, a corrective term dependent on the mechanical play affecting the flight control equipped with the series ram concerned.

Abstract: A self-actuating firearm comprising a frame, a breechblock, a barrel provided with a bore, a cylinder which is associated with the barrel and forms an internal chamber which is connected to the bore of the barrel, by means of a gas tap, and a piston which is at least partially accommodated in the chamber and can be actuated by the gases that arrive from the bore upon firing. The piston floats with respect to the cylinder and the frame and comprises a portion which is external to the cylinder and is adapted to act with an impulsive action on the breechblock in order to recock the firearm upon firing.

Abstract: Apparatus for estimating a first height (1) of a vehicle (2) above a first reference surface (3), including a system (4) for determining position, velocity and attitude incorporating at least one sensing means (4b) operable to provide an output signal (5) indicative of a vertical specific force of the vehicle, error-estimating means (6) for receiving as input signals a horizontal reference velocity and position (4a) of the vehicle (2), and a radar altimeter measurement (7) of a second height (1b) of the vehicle (2) above a second reference surface (8) and for providing as an output signal (9) estimates of errors associated with the sensing means output signal (5), and integrating means (10) for receiving said sensing means and error-estimating means output signals (5, 9), and for subtracting the estimates of errors from the signal (5) indicative of vertical specific force while performing a double integration of the results of the subtraction, to provide an output indicative of the required estimated first he

Abstract: An apparatus for providing lateral guidance through a plurality of waypoints utilizing curved path transitions. When the curved path transitions overlap due to a short leg there is a discontinuity in the desired path of the aircraft, causing the aircraft to experience excessive and oscillatory bank angles to maneuver through the turn. The invention adjusts the transition parameters so that there are no discontinuities in the flight path by computing a new turn radius, turn center, or turn center coordinates, in accordance with the course through the waypoints. The invention determines which flight plan legs are short and calculates the parameters so that the path will not violate air space boundaries and bank angles will be minimized. A circular path is generated tangential to course changes in the same or opposite direction, irrespective of the value of the flight plan leg length.