{"product_id":"apollo-pintle-injector-print","title":"Apollo Pintle Injector Print","description":"\u003cp\u003e\u003cstrong\u003eDesign\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eTo land on the Moon, the Lunar Module's descent engine had to throttle smoothly from full power down to a gentle hover. TRW solved it with a variable-area pintle injector. Oxidizer (nitrogen tetroxide) flowed down the centre and out past a fixed pintle as a ring of individual sprays. Fuel (Aerozine 50) left the faceplate as a thin cylindrical sheet, and the oxidizer sprays broke it up and mixed with it. A movable sleeve, linked to the flow control valves, changed the size of both openings at the same time, so the mixture stayed right at every thrust setting.\u003c\/p\u003e\n\u003cp\u003eThe engine throttled between 10% and 60% of its 10,500 lbf maximum, or ran at full thrust; the range between 65% and 92.5% was avoided to protect the nozzle. On Apollo 13 the same engine pushed the crippled spacecraft back towards Earth. The pintle injector design later went into SpaceX's Merlin engines.\u003c\/p\u003e\n\u003cp\u003eThis print is the fine-line edition of the drawing: the engine in half-section, with Detail A showing the fixed pintle, the movable sleeve and the two propellant paths.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eItem\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003ePrinted on heavyweight matte paper with a smooth, glare-free finish that suits fine line work. Shipped in protective packaging. Frame not included.\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003eCare instructions\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e- Keep out of direct sunlight to protect the print\u003c\/p\u003e","brand":"Printify","offers":[{"title":"12\" x 16\" \/ Matte","offer_id":47891110396102,"sku":"30968144810789750017","price":79.0,"currency_code":"USD","in_stock":true},{"title":"18″ x 24″ \/ Matte","offer_id":47891110428870,"sku":"14823066077885131821","price":119.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0703\/4424\/5446\/files\/16472213658967431112_2048.jpg?v=1790438731","url":"https:\/\/mach25.co\/products\/apollo-pintle-injector-print","provider":"Mach 25","version":"1.0","type":"link"}