{"product_id":"apollo-pintle-injector-framed-print","title":"Apollo Pintle Injector Framed 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 matte paper and set in a slim black frame, so the drawing reads like a sheet from the engineering office.\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\u003cbr\u003e- Wipe the frame with a dry cloth\u003c\/p\u003e","brand":"Printify","offers":[{"title":"12″ x 16″ \/ Black","offer_id":47891119964358,"sku":"21682108426798841000","price":129.0,"currency_code":"USD","in_stock":true},{"title":"16″ x 24″ \/ Black","offer_id":47891119997126,"sku":"23677955682807715728","price":179.0,"currency_code":"USD","in_stock":true},{"title":"20\" x 30\" \/ Black","offer_id":47891120029894,"sku":"12882570278661957659","price":229.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0703\/4424\/5446\/files\/4450459944881176531_2048.jpg?v=1790438775","url":"https:\/\/mach25.co\/products\/apollo-pintle-injector-framed-print","provider":"Mach 25","version":"1.0","type":"link"}