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
Center pivot irrigation point. Aerial views show fields of circles created by the watery tracings of "quarter- or half-mile of the center-pivot irrigation pipe," created by center pivot irrigators which use "hundreds and sometimes thousands of gallons a minute." Most center pivot systems now have drops hanging from a u-shaped pipe called a "gooseneck" attached at the top of the pipe with sprinkler heads that are positioned a few feet (at most) above the crop, thus limiting evaporative losses and wind drift. There are many different nozzle configurations available including static plate, moving plate and part circle. Pressure regulators are typically installed upstream