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
Bascinet A minority, including De Vries and Smith, class all smaller visors, those that only cover the area of the face left exposed by the aventail, as "klappvisiers", regardless of the construction of their hinge mechanism. However, they agree that "klappvisiers", by their alternate definition of 'being of small size', preceded the larger forms of visor, which almost exclusively employed the double pivot, found in the latter part of the 14th century. The side-pivot mount, which used two pivots – one on each side of the helmet, is shown in funerary monuments and other pictorial or sculptural sources of the 1340s.