Pintle exotic metal alloys. For World War II aircraft with sideways-retracting main gear units, carefully set-up "pintle angles" for such axes of rotation during retraction and extension allowed the maingear struts to be raked forward while fully extended for touchdown and better ground handling, while permitting retraction into rearwards-angled landing gear wells in their wings to usually clear the forward wing spar for stowing while in flight. Pintle A pintle is a pin or bolt, usually inserted into a gudgeon, which is used as part of a pivot or hinge. Other applications include pintle and lunette ring for towing, and pintle
Pin tumbler lock horizontal bolt that slid into the post. The bolt had vertical openings into which a set of pins fitted. These could be lifted, using a key, to a sufficient height to allow the bolt to move and unlock the door. This wooden lock was one of Egypt's major developments in domestic architecture during classical times. Such a lock, however, may be defeated by lifting the pins uniformly beyond the unlatching point. In 1805, the earliest patent for a double-acting pin tumbler lock — one where lifting the pins too much or too little prevented opening — was granted to American