{
  "id": "grumman-lunar-module-descent-engine",
  "title": "Lunar Module Descent Engine (LMDE)",
  "maker": "TRW (Space Technology Laboratories) for Grumman and NASA",
  "maker_type": "Commercial",
  "kind": "mission",
  "category": "engines",
  "page": "https://spacemushroom.com/space-products/grumman-lunar-module-descent-engine/",
  "website": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
  "summary": "TRW's throttleable, pintle-injector hypergolic engine that landed the Apollo Lunar Module; sources name a titanium case with a silica/phenolic ablative liner, a thin columbium C-103 nozzle extension and a stainless-steel, then columbium, pintle tip.",
  "application": "One LMDE sat in the central bay of each Lunar Module descent stage and slowed the vehicle from lunar orbit to a hover and landing, throttling down to about a tenth of its rated thrust. NASA Marshall says the pintle injector of SpaceX's Merlin 1D was first used in this Apollo-era engine.",
  "story": null,
  "specifications": [
    {
      "label": "Maximum thrust (vacuum, full throttle position)",
      "value": "10,500 lbf",
      "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
      "quote": "10,500 lbT"
    },
    {
      "label": "Maximum nominal thrust (introduction)",
      "value": "9,850 lbf",
      "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
      "quote": "9,850 lbT maximum nominal thrust"
    },
    {
      "label": "Throttle range",
      "value": "10:1 (minimum about 10 percent of rated thrust)",
      "source_url": "https://www.nasa.gov/wp-content/uploads/2023/04/sp-4545.pdf",
      "quote": "we were throttling 10:1 with good performance"
    },
    {
      "label": "Minimum throttle point",
      "value": "10 percent of rated thrust",
      "source_url": "https://ntrs.nasa.gov/api/citations/19730011150/downloads/19730011150.pdf",
      "quote": "The minimum-throttle point was 10 percent of the rated thrust."
    },
    {
      "label": "Propellants",
      "value": "Aerozine 50 fuel and nitrogen tetroxide oxidizer, hypergolic",
      "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
      "quote": "storable hypergolic Aerozine 50 fuel and nitrogen tetroxide oxidizer"
    },
    {
      "label": "Specific impulse",
      "value": "305 s (end of duty cycle)",
      "source_url": "https://ntrs.nasa.gov/api/citations/19730011150/downloads/19730011150.pdf",
      "quote": "Specific impulse (end of duty cycle): 305 lbf-sec/lbm"
    },
    {
      "label": "Chamber pressure (full throttle position)",
      "value": "103.4 psia",
      "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
      "quote": "103.4 psia"
    },
    {
      "label": "Ablative chamber area ratio",
      "value": "16:1",
      "source_url": "https://www.nasa.gov/wp-content/uploads/2023/04/sp-4545.pdf",
      "quote": "the thrust chamber design had a titanium case lined with ablative material out to a nozzle expansion ratio of 16:1"
    },
    {
      "label": "Nozzle extension area ratio",
      "value": "About 48:1",
      "source_url": "https://www.nasa.gov/wp-content/uploads/2023/04/sp-4545.pdf",
      "quote": "Then, we had a columbium nozzle extension from there out to 48:1."
    },
    {
      "label": "Approximate weight",
      "value": "394 lb",
      "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
      "quote": "394 lb"
    },
    {
      "label": "Ablative duty-cycle capability",
      "value": "1,000 s",
      "source_url": "https://www.nasa.gov/wp-content/uploads/2023/04/sp-4545.pdf",
      "quote": "This engine had to run for 1,000 seconds ablatively"
    },
    {
      "label": "Engines per vehicle",
      "value": "1 in the Lunar Module descent stage",
      "source_url": "https://ntrs.nasa.gov/api/citations/19730011150/downloads/19730011150.pdf",
      "quote": "The descent engine was located in the central bay of the descent stage"
    },
    {
      "label": "Design selection",
      "value": "NASA selected the STL design as primary in December 1964",
      "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
      "quote": "Then in December 1964, NASA selected the STL design as primary."
    },
    {
      "label": "First flight engine delivered",
      "value": "August 1966",
      "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
      "quote": "Grumman received the first flight engine in August 1966."
    },
    {
      "label": "First flight",
      "value": "Apollo 5 (LM-1), Saturn IB, 22 January 1968; first descent burn cut short after 4 s",
      "source_url": "https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1968-007A",
      "quote": "A planned descent propulsion system (DPS) of 39 seconds was cut short after only 4 seconds."
    },
    {
      "label": "First flight date",
      "value": "1968-01-22",
      "source_url": "https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1968-007A",
      "quote": "Launch Date: 1968-01-22"
    }
  ],
  "features": [
    {
      "text": "Single-element injector with a sliding sleeve meters oxidizer (centre) and fuel (outer annulus) together",
      "source_url": "https://www.nasa.gov/wp-content/uploads/2023/04/sp-4545.pdf",
      "quote": "The injector has a sliding sleeve that controls both the oxidizer in the middle and the fuel coming down the outside."
    },
    {
      "text": "Sleeve is linked 1:1 to two cavitating venturi flow-control valves that fix flow independent of injector pressure",
      "source_url": "https://www.nasa.gov/wp-content/uploads/2023/04/sp-4545.pdf",
      "quote": "That was linked 1:1 with two cavitating venturi valves"
    },
    {
      "text": "Ablatively lined chamber with a fuel barrier coolant, rated for 1,000 seconds",
      "source_url": "https://www.nasa.gov/wp-content/uploads/2023/04/sp-4545.pdf",
      "quote": "We used a barrier coolant in the engine because it was ablatively lined."
    },
    {
      "text": "Chamber liner is oriented silica fabric",
      "source_url": "https://www.nasa.gov/wp-content/uploads/2023/04/sp-4545.pdf",
      "quote": "We ended up with oriented silica fabric on the inside."
    },
    {
      "text": "Nozzle extension is extremely thin so it crushes on surface impact",
      "source_url": "https://www.nasa.gov/wp-content/uploads/2023/04/sp-4545.pdf",
      "quote": "That nozzle had to be like seven-thousandths of an inch at the exit cone"
    },
    {
      "text": "Pintle tip erosion ended when the tip was changed to columbium alloy",
      "source_url": "https://ntrs.nasa.gov/api/citations/19730011150/downloads/19730011150.pdf",
      "quote": "No erosion occurred with the columbium tip."
    },
    {
      "text": "Y-baffle on the injector face damps combustion instability",
      "source_url": "https://ntrs.nasa.gov/api/citations/19730011150/downloads/19730011150.pdf",
      "quote": "A Y-baffle arrangement was incorporated on the injector face to damp"
    },
    {
      "text": "NASA ran two throttling concepts in parallel for about 18 months before choosing the variable-area injector",
      "source_url": "https://ntrs.nasa.gov/api/citations/19730011150/downloads/19730011150.pdf",
      "quote": "the variable-area-injector throttling concept was selected (January 1965)"
    },
    {
      "text": "Spring-loaded throttle drives the engine to full thrust if electric power is lost",
      "source_url": "https://www.nasa.gov/wp-content/uploads/2023/04/sp-4545.pdf",
      "quote": "if we lost any electric power, the engine automatically would go to full-thrust position"
    },
    {
      "text": "NASA Marshall says the Merlin 1D pintle injector was first used in this Apollo engine",
      "source_url": "https://www.nasa.gov/missions/station/nasa-marshall-spacex-team-celebrates-engines-of-success/",
      "quote": "incorporates a pintle injector first used in the Apollo-era Lunar Module landing engine"
    }
  ],
  "parts": [
    {
      "assembly": "Thrust chamber",
      "parts": [
        {
          "part": "Chamber and exit-cone forgings",
          "material": "titanium alloy 6Al-4V (printed 6A1-4V in the source)",
          "form": "machined forgings welded into one unit at the throat",
          "finish": null,
          "standard": null,
          "hardware_ref": "Source says the engine chamber and exit cone portions",
          "quote": "machined from 6A1-4V titanium alloy forgings",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": "titanium-6al-4v"
        },
        {
          "part": "Ablative-lined case to 16:1",
          "material": "titanium alloy (grade stated for the forgings only)",
          "form": "case",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "an ablative-lined titanium alloy case to the 16:1 area ratio",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": "titanium",
          "mid": "titanium"
        },
        {
          "part": "Ablative liner",
          "material": "silica cloth / phenolic ablative",
          "form": "ablative liner with fuel barrier cooling",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "a high density, erosion-resistant silica cloth/phenolic material",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": "silica-phenolic-ablator"
        },
        {
          "part": "Liner insulation layer",
          "material": "metal felt (alloy not stated)",
          "form": "insulator outside the liner",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "we had a lightweight metal felt material as an insulator outside of that in the chamber",
          "source_url": "https://www.nasa.gov/wp-content/uploads/2023/04/sp-4545.pdf",
          "profile": null,
          "mid": "metal-felt-insulation"
        },
        {
          "part": "Structural shield",
          "material": "titanium",
          "form": "shield around the insulated liner",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "that had a titanium structural shield around it",
          "source_url": "https://www.nasa.gov/wp-content/uploads/2023/04/sp-4545.pdf",
          "profile": "titanium",
          "mid": "titanium"
        },
        {
          "part": "Head-end attachment bolts (36)",
          "material": "A-286 steel",
          "form": "0.250 inch bolts per the source",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "36 A-286 steel",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": "a-286-steel"
        },
        {
          "part": "Exit-plane stiffening ring",
          "material": "titanium",
          "form": "I-shaped ring",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "an I-shaped titanium ring provided stiffness during handling, launch and boost",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": "titanium",
          "mid": "titanium"
        },
        {
          "part": "Fuel barrier cooling",
          "material": null,
          "form": "fuel barrier film along the chamber wall",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "We used a barrier coolant in the engine because it was ablatively lined.",
          "source_url": "https://www.nasa.gov/wp-content/uploads/2023/04/sp-4545.pdf",
          "profile": null,
          "mid": null
        }
      ]
    },
    {
      "assembly": "Nozzle extension",
      "parts": [
        {
          "part": "Nozzle extension skirt (16:1 to about 48:1)",
          "material": "Columbium alloy C-103",
          "form": "very thin sheet skirt, radiation cooled",
          "finish": null,
          "standard": null,
          "hardware_ref": "NASA TN D-7143 calls it a sheet-metal columbium-alloy skirt; The Wah Chang Company supplied it",
          "quote": "Columbium alloy C-103 was selected as the nozzle extension material",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": "niobium-c-103"
        },
        {
          "part": "Nozzle extension coating",
          "material": "aluminide coating",
          "form": "oxidation-resistant coating",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "An aluminide coating provided oxidation resistance and high emissivity.",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": "aluminide-coating"
        }
      ]
    },
    {
      "assembly": "Injector",
      "parts": [
        {
          "part": "Pintle tip, original",
          "material": "stainless steel (grade not stated)",
          "form": "pintle tip",
          "finish": null,
          "standard": null,
          "hardware_ref": "Eroded because of inadequate cooling",
          "quote": "The original injector pintle tip was made of stainless steel",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": "stainless-steel"
        },
        {
          "part": "Pintle tip, copper-slug version",
          "material": "copper",
          "form": "copper slugs in the tip",
          "finish": null,
          "standard": null,
          "hardware_ref": "Phase A qualification design",
          "quote": "copper slugs were incorporated in the pintle tip",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": "copper",
          "mid": "copper"
        },
        {
          "part": "Pintle tip, qualification version",
          "material": "columbium alloy (grade not stated)",
          "form": "pintle tip",
          "finish": null,
          "standard": null,
          "hardware_ref": "Phase B qualification; no erosion occurred",
          "quote": "used a columbium-alloy pintle tip",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": "columbium-niobium"
        },
        {
          "part": "Variable-area sleeve",
          "material": null,
          "form": "single moving sleeve linked to the flow-control valves",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "The injector has a sliding sleeve that controls both the oxidizer in the middle and the fuel coming down the outside.",
          "source_url": "https://www.nasa.gov/wp-content/uploads/2023/04/sp-4545.pdf",
          "profile": null,
          "mid": null
        },
        {
          "part": "Injector face baffle",
          "material": null,
          "form": "Y-shaped baffle",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "A Y-baffle arrangement was incorporated on the injector face to damp",
          "source_url": "https://ntrs.nasa.gov/api/citations/19730011150/downloads/19730011150.pdf",
          "profile": null,
          "mid": null
        }
      ]
    },
    {
      "assembly": "Propellant flow control",
      "parts": [
        {
          "part": "Cavitating venturi flow-control valves (2)",
          "material": null,
          "form": "cavitating venturis",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "The flow control valves were non-redundant cavitating venturis with movable pintle sleeves.",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": null
        },
        {
          "part": "Flow-control valve elbow, original",
          "material": "6061 aluminium",
          "form": "stamped sheet",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "The original flow control valve (FCV) elbow was made of stamped 6061 aluminum sheet",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": "aluminium-6061",
          "mid": "aluminium-6061"
        },
        {
          "part": "Flow-control valve elbow, redesigned",
          "material": "6061 aluminium",
          "form": "two machined pieces",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "The new elbow consisted of two pieces machined from solid 6061 aluminum",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": "aluminium-6061",
          "mid": "aluminium-6061"
        },
        {
          "part": "Flow-control valve bellows",
          "material": "stainless steel (grade not stated)",
          "form": "thin-wall welded bellows",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "stainless steel welded bellows",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": "stainless-steel"
        },
        {
          "part": "Propellant shutoff valves",
          "material": null,
          "form": "ball valves",
          "finish": null,
          "standard": null,
          "hardware_ref": "NASA SP-2009-4545: quad ball valves on the fuel and oxidizer sides",
          "quote": "The propellant shutoff valves were ball valves.",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": null
        },
        {
          "part": "Throttle actuator",
          "material": null,
          "form": "electric actuator, triple redundant",
          "finish": null,
          "standard": null,
          "hardware_ref": "Bendix Commercial Vehicle Systems",
          "quote": "built by Bendix Commercial Vehicle Systems",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": null
        },
        {
          "part": "Throttle linkage pivot",
          "material": "steel coated with molybdenum disulfide (inorganic binder)",
          "form": "bushing and pin",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "a steel bushing and a steel pin, both coated with molybdenum disulfide with an inorganic binder",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": "molybdenum-disulfide-coating"
        }
      ]
    },
    {
      "assembly": "Gimbal and heat shield",
      "parts": [
        {
          "part": "Gimbal frame",
          "material": "7075-T73 aluminium alloy",
          "form": "machined frame",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "machined from 7075-T73 aluminum alloy",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": "aluminium-7075-t73"
        },
        {
          "part": "Gimbal trunnion bearings",
          "material": "Fabroid",
          "form": "spherical bearing",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "a spherical Fabroid bearing",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": "fabroid"
        },
        {
          "part": "Gimbal actuators",
          "material": null,
          "form": "actuators",
          "finish": null,
          "standard": null,
          "hardware_ref": "Airesearch Mfg. Company of Los Angeles",
          "quote": "built by Airesearch Mfg. Company of Los Angeles",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": null
        },
        {
          "part": "Radiation heat shield foil",
          "material": "stainless steel foil (grade not stated)",
          "form": "two thin foil layers",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "stainless steel foil separated by fiberglass wool",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": "stainless-steel"
        },
        {
          "part": "Radiation heat shield spacer",
          "material": "fiberglass wool",
          "form": "wool between the foil layers",
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "stainless steel foil separated by fiberglass wool",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": "fiberglass"
        }
      ]
    },
    {
      "assembly": "Propellants",
      "parts": [
        {
          "part": "Fuel",
          "material": "Aerozine 50",
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "storable hypergolic Aerozine 50 fuel and nitrogen tetroxide oxidizer",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": "aerozine-50"
        },
        {
          "part": "Oxidizer",
          "material": "nitrogen tetroxide",
          "form": null,
          "finish": null,
          "standard": null,
          "hardware_ref": null,
          "quote": "storable hypergolic Aerozine 50 fuel and nitrogen tetroxide oxidizer",
          "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml",
          "profile": null,
          "mid": "dinitrogen-tetroxide"
        }
      ]
    }
  ],
  "materials": [
    {
      "id": "titanium-6al-4v",
      "name": "titanium alloy 6Al-4V (printed 6A1-4V in the source)",
      "material_page": null
    },
    {
      "id": "titanium",
      "name": "titanium",
      "material_page": "https://spacemushroom.com/profiles/titanium/"
    },
    {
      "id": "silica-phenolic-ablator",
      "name": "silica cloth / phenolic ablative",
      "material_page": null
    },
    {
      "id": "metal-felt-insulation",
      "name": "metal felt (alloy not stated)",
      "material_page": null
    },
    {
      "id": "a-286-steel",
      "name": "A-286 steel",
      "material_page": null
    },
    {
      "id": "niobium-c-103",
      "name": "Columbium alloy C-103",
      "material_page": null
    },
    {
      "id": "aluminide-coating",
      "name": "aluminide coating",
      "material_page": null
    },
    {
      "id": "stainless-steel",
      "name": "stainless steel foil (grade not stated)",
      "material_page": null
    },
    {
      "id": "copper",
      "name": "copper",
      "material_page": "https://spacemushroom.com/profiles/copper/"
    },
    {
      "id": "columbium-niobium",
      "name": "columbium alloy (grade not stated)",
      "material_page": null
    },
    {
      "id": "aluminium-6061",
      "name": "6061 aluminium",
      "material_page": "https://spacemushroom.com/profiles/aluminium-6061/"
    },
    {
      "id": "molybdenum-disulfide-coating",
      "name": "steel coated with molybdenum disulfide (inorganic binder)",
      "material_page": null
    },
    {
      "id": "aluminium-7075-t73",
      "name": "7075-T73 aluminium alloy",
      "material_page": null
    },
    {
      "id": "fabroid",
      "name": "Fabroid",
      "material_page": null
    },
    {
      "id": "fiberglass",
      "name": "fiberglass wool",
      "material_page": null
    },
    {
      "id": "aerozine-50",
      "name": "Aerozine 50",
      "material_page": null
    },
    {
      "id": "dinitrogen-tetroxide",
      "name": "nitrogen tetroxide",
      "material_page": null
    }
  ],
  "standards": [],
  "relations": [
    {
      "type": "part_of",
      "target": "Apollo Lunar Module (descent stage)",
      "target_slug": "grumman-apollo-lunar-module",
      "note": "One engine in the descent stage; first in-flight burn on Apollo 5 (LM-1)",
      "quote": "The descent engine was located in the central bay of the descent stage",
      "source_url": "https://ntrs.nasa.gov/api/citations/19730011150/downloads/19730011150.pdf"
    },
    {
      "type": "supplied_by",
      "target": "TRW (Space Technology Laboratories)",
      "target_slug": null,
      "note": "Designer and builder of the flight engine",
      "quote": "developed by a few engineers at a space engineering company called Space Technology Laboratories",
      "source_url": "https://www.nasa.gov/wp-content/uploads/2023/04/sp-4545.pdf"
    },
    {
      "type": "supplied_by",
      "target": "Wah Chang Company",
      "target_slug": null,
      "note": "Columbium nozzle extension and its coating",
      "quote": "The Wah Chang Company supplied the very thin columbium nozzle and coatings.",
      "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml"
    },
    {
      "type": "supplied_by",
      "target": "Bendix Commercial Vehicle Systems",
      "target_slug": null,
      "note": "Electric throttle actuator",
      "quote": "The actuator was an electrical actuator done by Bendix Commercial Vehicle Systems.",
      "source_url": "https://www.nasa.gov/wp-content/uploads/2023/04/sp-4545.pdf"
    },
    {
      "type": "supplied_by",
      "target": "Airesearch Mfg. Company",
      "target_slug": null,
      "note": "Gimbal actuators",
      "quote": "built by Airesearch Mfg. Company of Los Angeles",
      "source_url": "https://enginehistory.org/Rockets/RPE09.42/RPE09.42.shtml"
    }
  ],
  "not_published": "No standards; the metal felt alloy, ball-valve and venturi alloys are not stated.",
  "depth": "partial",
  "photos": [],
  "context": {
    "size": [],
    "mass": [],
    "orbit": []
  },
  "licence": "Product data CC BY 4.0, cite Space Mushroom. Photos keep their own licences, given per photo.",
  "mcp": "https://spacemushroom.com/mcp"
}