Abstract: A parachute release device enabling an automatic opening of the parachute during a fall of an object of a person to which the parachute is attached. The parachute release device determines the height at which the parachute is to be opened and is provided with means for a operating a parachute opening device. This device comprises position determination means determining a reference vector, based upon the earth's magnetic field, used for filtering and adjusting the position of the object in a three axis coordinate reference system, whereby the filtering is performed by omitting inaccurate data generated during an inappropriate orientation of the object or person during the fall thereof.