Fire-fighting aviators of the northwestern timberlands and parachute troops of the U. S. Army are pioneering a new technique that makes it unnecessary for the jumper to worry about pulling his rip cord at just the right moment. The ’chute is opened automatically when the jumper is a safe distance beneath the plane, a sturdy line attached to the airplane pulling the rip cord and then breaking loose from the plane. This method is used by the parachutists of the U. S. Forest Service who drop from the sky to strategic spots for fighting forest fires, and is now being prac- ticed by the army parachutists who are undergoing a special training course at Fort Benning, Ga. Until now, teaching the beginner the exact moment to release his parachute has been considered one of the most difficult parts of the training.