Month in the Patent Office Available to Purchase

An aircraft hood jettisoning system includes at least two jacks 13 placed for jettisoning the hood, each being operable by a detachable explosive having a firing pin, and passages 30 connected to all the jacks 13 to provide an operating pressure for actuating the firing pins, which pressure is derived from a primary cartridge or the like 24, when fired. In FIG. 1, a plurality of primary cartridges 26 are provided, situated at convenient points in the aircraft. Each cartridge can be fired by pulling its handle 25 against a spring 26, releasing a spring urged firing pin to detonate the cartridge and fill the passage 30 with gas under pressure. The firing pin of such jack 13 is spaced from its firing cap by a rubber ring. When passage 30 is filled with gas under pressure, the firing pin compresses the rubber ring and fires the jack to raise its piston 22. During the first part of its stroke, the piston 22 rotates two bell cranks 15 about pivots 15a to pull on two rods 14, which release fastenings of rails on which the hood slides (not shown). The remainder of the piston stroke raises the rails and hood into the airstream. As shown in FIG. 2, the cranks 15 are also each connected by a link 16 to a plate 17 secured to a shaft 18 on which is secured a pinion 19 meshing with a rack 20. The rack can be moved manually to effect release of the rail fastings at any time. The primary cartridge may be detonated by the pilot pulling down a protective face shield which also operates ejector mechanism. The piston 22 of the jacks 13 may be formed in two telescoping portions.