Abstract: A hand-held device for the determination of the momentary position of a vehicle, especially an airplane, moving at least approximately in a straight line and at about constant speed, has two compass legs each having a compass point and a lock movement having a drive shaft for driving at least one of the compass legs which is pivotable about a pivot pin. In order to largely eliminate the chord defect, the pivot pin of the drivable leg of the compass is movable in a straight line in a guide slot as a function of speed and the drive shaft moves the drivable leg as a function of time.