Patent ID: 7111807

Claim:
In an aircraft catapult for launching an unmanned aircraft, the improvements comprising: an elongated frame; a first carriage that is movable in a longitudinal direction of the frame from a launch position to a release position and back, and which first carriage comprises securing means for supporting the aircraft; a second carriage that is movable in the longitudinal direction of the frame; at least one launching cylinder that is pressure-medium-operated and that is arranged to move the second carriage at least in one direction; at least one pulley mechanism that comprises at least one pulley and that is arranged in connection with the second carriage; at least one pulling element that is engaged with the first carriage and the frame, and which pulling element is further arranged to run via at least one launch-side pulley mechanism and to transmit the motion of the second carriage to the first carriage using a predetermined transmission ratio provided by the pulley mechanism for moving the first carriage from the launch position to the release position; at least one locking device for locking and unlocking the first carriage in the launch position; at least one damper that is arranged to make the first carriage halt in the release position; at least one returning device that is arranged to return the first carriage from the release position to the launch position; and at least one return-side pulley mechanism in connection with the second carriage and comprising at least one pulley, wherein the pulling element comprises a launch-side portion acting from the first carriage in the launch direction and a return-side portion acting in the return direction, the return-side portion of the pulling element is arranged to run through the return-side pulley mechanism so as to provide a predetermined transmission ratio, the returning device is arranged to transfer the second carriage in the return direction that is opposite to the launch direction, the launch-side pulley mechanism and the return-side pulley mechanism have substantially the same transmission ratio, whereby the transfer of the second carriage in either direction of motion is arranged to move the first carriage for substantially the same distance, the launching cylinder is pneumatic, the launching cylinder is connected through a channel to at least one pressure accumulator, which can accumulate the gas required for one launch, the return motion of the second carriage is arranged to generate a return motion of the launching cylinder and a rise in the gas pressure in the working pressure space of the launching cylinder, the rise in the gas pressure resulting from the return motion of the launching cylinder is arranged to be transmitted to the pressure accumulator for a new launch, and the launching cylinder is connected to a substantially closed compressed air circuit.