The Apollo Lunar Module was the two-stage Grumman lander that took astronauts down to the Moon.
grumman-apollo-lunar-module Grumman built the Apollo Lunar Module for NASA as a two-stage lander for a crew of two. The descent stage landed on the Moon and was also the launch platform for the ascent stage, which carried the two astronauts back to orbit to meet the command module. It was left behind on the Moon.
The lander was designed to work only in space, with a minimum-weight structure. Its structure weighed about one fifteenth of the fully loaded spacecraft. The lander is mostly aluminium alloy, with titanium where it gets hot. Layers of metal and plastic film wrap both stages in a shield against heat and micrometeoroids, which are tiny grains of space dust.
Two-stage crewed lunar lander used on Apollo missions 5 to 17 for crew landing on the Moon (four landings among the ten missions covered by the structural report). The descent stage landed and served as launch platform; the ascent stage carried two astronauts back to orbit to meet the command module.
The ascent stage is built mainly from aluminium alloys. The major ones are 2219 and 7075-T6, and some brackets and fasteners are titanium. The cabin is a cylindrical shell 92 inches across.
The cabin windows have two panes. The outer one, made of Vycor glass, is not structural and guards against micrometeoroids and radiation. The inner one, made of tempered Chemcor glass, is the structural pane, sealed by a metallic spring inside a Teflon jacket.
The descent stage is mostly 7075-T6 aluminium alloy, with titanium where temperatures are high. Some struts in that alloy developed stress-corrosion cracking, a slow cracking of metal under constant stress, so the heat treatment was changed to one called T73. Crushable honeycomb cartridges in the landing gear absorb the shock of touchdown.
The descent engine has its own heat protection. A base heat shield is built from alternating layers of nickel foil and a material called Fiberfrax, held on standoffs fixed to a titanium frame. A blast shield of Teflon-coated titanium sits on the upper edge of the engine compartment.
Both stages are wrapped in a thermal blanket under an outer aluminium micrometeoroid shield. The blanket's core is many layers of aluminised Mylar film, enclosed in aluminised Kapton film. Near the engine plumes, foils and mesh of Inconel and nickel replace the blanket and the aluminium skin.
Most of the descent stage structure, and a major alloy of the ascent stage alongside alloy 2219.
Ascent-stage brackets and fasteners, hot areas of the descent stage, and the frame of the base heat shield.
Foil and mesh in the shield areas near the engine plumes, and in the thruster plume deflector.
The core of the thermal blanket, as thin aluminised polyester film in many layers.
The inner, structural pane of the cabin windows.
Alternating layers that insulate the base heat shield, held on standoffs fixed to a titanium frame.
Grumman built the lander for NASA, and it was used on Apollo missions 5 to 17. The Apollo 11 lander launched on 16 July 1969 on a Saturn V from Cape Canaveral.
TRW
TRW; one throttleable 9,850 to 10,500 lbf engine in the descent stage
Rocketdyne/Bell, designation RS-1801; one 3,500 lbf fixed-thrust engine in the ascent stage midsection
Reaction control thruster, Marquardt; sixteen 100 lbf thrusters in four ascent-stage clusters
The first LM test flight (uncrewed LM-1, AS-204) launched on a Saturn IB
Rocketdyne, Division of North American Aviation
Five on the Saturn V S-IC first stage; Saturn V first-stage engines under the stack that carried the LM; launcher engine, not carried by the vehicle
Rocketdyne
Five on the Saturn V S-II second stage; Saturn V second-stage engines; launcher engine, not carried by the vehicle
One restartable engine on the S-IVB; Saturn V third-stage engine; launcher engine, not carried by the vehicle
Eight on the Saturn IB S-IB first stage; Saturn IB first-stage engines for the LM-1 flight; launcher engine, not carried by the vehicle
Designed and built the lunar module
Descent engine developer selected by NASA and Grumman
Ascent engine injector and final assembly
Ascent engine development; Bell also supplied the valves, thrust chamber and RCS tanks
100 lbf reaction control thrusters
Environmental control subsystem
Ascent and descent stage silver-zinc batteries
Columbium nozzle extension of the descent engine
Descent engine throttle valve actuator
Descent engine gimbal drive actuators (and the supercritical helium tanks)
Later descent propellant tanks and ascent helium tanks
Initial descent propellant tanks
Ascent propellant tanks
Apollo Guidance Computer design used as the LM guidance computer
North American Aviation
R-4D engine. Here: Reaction control thruster, Marquardt; sixteen 100 lbf thrusters in four ascent-stage clusters. There: Reaction control engine, Marquardt; sixteen ~100 lbf engines in four service module quads.
NASA
Titanium. Here: Some brackets and fasteners (lunar module); Descent-stage hot-area structure and more. There: Outboard engine fairings and stabilization fins; Control pressure nitrogen bottle (2,200 cubic in) and more.
Aluminium. Here: Cabin front-face, RCS cluster trusses, decks and bulkheads; Micrometeoroid shield and more. There: S-IVB forward skirt, aft skirt, thrust structure and aft interstage.
Aluminium alloy 7075-T6. Here: Ascent-stage structure (major alloy); Descent-stage main structure (beams, decks, bulkheads). There: Thrust structure skin panels; Intertank and more.
Inconel foil and Inconel mesh. Here: Plume-exposed shield areas; RCS plume deflector. There: Q-ball and nose cone.
Silver-zinc plates with potassium hydroxide electrolyte. Here: Descent stage batteries (x5, silver-zinc); Ascent stage batteries (x2, silver-zinc). There: Flight batteries (x4 zinc-silver oxide); Flight batteries (x4 zinc/silver-oxide) and more.
Aluminium alloy 2219. Here: Ascent-stage cabin, midsection and aft equipment bay shell. There: LOX tank skin.
North American Aviation
Titanium. Here: Some brackets and fasteners (lunar module); Descent-stage hot-area structure and more. There: Helium tanks (2); Fuel tanks (2) and more.
Aluminium. Here: Cabin front-face, RCS cluster trusses, decks and bulkheads; Micrometeoroid shield and more. There: Radial beams; Crushable ribs (x4) and more.
Aluminum honeycomb. Here: Primary struts with crushable aluminum-honeycomb cartridge; Footpads (x4, aluminum honeycomb). There: Inner pressure shell (crew compartment); Sector and RCS exterior panels (1 in thick).
Inconel foil and Inconel mesh. Here: Plume-exposed shield areas; RCS plume deflector. There: Cryogenic oxygen tanks; Q-ball instrument package and Inconel nose cone.
Silver-zinc plates with potassium hydroxide electrolyte. Here: Descent stage batteries (x5, silver-zinc); Ascent stage batteries (x2, silver-zinc). There: Silver oxide-zinc batteries in the command module (x5).
Boeing
Titanium. Here: Some brackets and fasteners (lunar module); Descent-stage hot-area structure and more. There: Tread chevrons; Inner frame (MESH-1 prototype wheel; flight material not stated).
Aluminium. Here: Cabin front-face, RCS cluster trusses, decks and bulkheads; Micrometeoroid shield and more. There: Hub and wheel disc (MESH-1 prototype wheel).
Silver-zinc plates with potassium hydroxide electrolyte. Here: Descent stage batteries (x5, silver-zinc); Ascent stage batteries (x2, silver-zinc). There: Batteries (2).
Aluminium alloy 2219. Here: Ascent-stage cabin, midsection and aft equipment bay shell. There: Frame.
NASA
Titanium. Here: Some brackets and fasteners (lunar module); Descent-stage hot-area structure and more. There: Heat shield skeleton.
Aluminium. Here: Cabin front-face, RCS cluster trusses, decks and bulkheads; Micrometeoroid shield and more. There: Pressure vessel (seven large pieces, friction-stir welded); Backbone assembly (floor structure) and more.
Aluminum honeycomb. Here: Primary struts with crushable aluminum-honeycomb cartridge; Footpads (x4, aluminum honeycomb). There: CFRP sandwich panel core.
Aluminium alloy 2219. Here: Ascent-stage cabin, midsection and aft equipment bay shell. There: Longeron (Orion ground test article).
ESA
Titanium. Here: Some brackets and fasteners (lunar module); Descent-stage hot-area structure and more. There: Focal plane interconnecting structure; Instrument mounting feet / flexures and more.
Aluminium. Here: Cabin front-face, RCS cluster trusses, decks and bulkheads; Micrometeoroid shield and more. There: Telescope (structure and mirrors, 3 telescopes).
Aluminium alloy 7075-T6. Here: Ascent-stage structure (major alloy); Descent-stage main structure (beams, decks, bulkheads). There: Edge profiles and hot inserts.
NASA Goddard Space Flight Center
Titanium. Here: Some brackets and fasteners (lunar module); Descent-stage hot-area structure and more. There: Propellant tanks (2); Instrument mounting flexures.
Aluminium. Here: Cabin front-face, RCS cluster trusses, decks and bulkheads; Micrometeoroid shield and more. There: Primary structure (heating/cooling panel, edge members, fittings, brackets); Optical-bench heater aluminum tape and more.
Aluminum honeycomb. Here: Primary struts with crushable aluminum-honeycomb cartridge; Footpads (x4, aluminum honeycomb). There: Iso-thermal panel with embedded heat pipes.
The alloys of the propellant, oxygen and helium tanks, the landing-gear honeycomb and the cabin hatch are not named, and nor are the materials of the two engines. Published layer counts for the thermal blanket differ between landers. The masses here are for the Apollo 11 lander only.
What is written above is built from these numbers and quotes. Each row links to the page it was taken from. Get all of it as JSON, or ask our MCP server.
| What | Value |
|---|---|
| Total mass (Apollo 11 LM-5) | 15,103 kg incl. propellants |
| Ascent stage dry mass | 2,445 kg |
| Descent stage dry mass | 2,034 kg incl. stowed surface equipment |
| Descent stage size | Octagonal prism, 4.2 m across, 1.7 m thick |
| Ascent stage size | About 2.8 m high, 4.0 by 4.3 m wide |
| Cabin diameter | 92 inches |
| Crew compartment volume | 6.65 cubic meters |
| Launch (Apollo 11 LM) | 16 July 1969, Saturn 5, Cape Canaveral |
| Structural mass ratio | about 1 to 15 of structural weight to fully loaded weight |
| Destination | Moon surface (four landings in 10 Apollo missions) |
| Height with legs extended | 22.92 ft |
| Diameter across extended landing gear | 31.00 ft measured diagonally |
| Earth-launch mass (Apollo News Reference) | About 36,100 lb with crew and propellant |
| Dry mass of the whole LM | About 10,800 lb |
| Ascent stage propellant mass | 5,200 lb |
| Descent stage propellant mass | 19,500 lb |
| Ascent stage RCS propellant mass | 600 lb |
| Habitable volume | 160 cubic ft |
| Cabin pressure | 4.8 plus or minus 0.2 psia |
| Crew compartment depth | Cylindrical, 92 in diameter and 42 in deep |
| Flight station spacing | Flight-station centerlines 44 in apart |
| Front window area | Each triangular front window has about 2 square ft of viewing area |
| Docking window area | About 80 square in |
| Engine count | 18 engines: two large rockets (descent and ascent) plus small attitude control engines |
| Ascent engine thrust (NASA SP-4205) | About 15,500 N (3,500 lbf) |
| Ascent engine thrust (NSSDC) | About 15,000 N |
| Descent engine thrust (NSSDC) | About 45,000 N maximum |
| Apollo 11 LM lunar surface stay | 21 hours 36 minutes |
| Lunar roving vehicle use | Allowed travel up to 5 km from touchdown on the later three missions |
| Descent propellant remaining at low-level warning | Enough for only 2 minutes of burn at hover thrust |
| Landing radar acquisition | Altitude data from about 38,000 ft, velocity data from about 25,000 ft |
| Late-mission descent engine changes | Apollo 15, 16 and 17 engines had a 10 in skirt extension and a quartz liner |
Each material named in the sources: where it is used here, which other products use it, and its key numbers when its material page exists.
Used in 6 partsSome brackets and fasteners (lunar module) · Descent-stage hot-area structure · Base heat shield support structure · +3 more
Used in 3 partsCabin front-face, RCS cluster trusses, decks and bulkheads · Micrometeoroid shield · RCS cluster frames and thermal shields (x4)
Used in 2 partsAscent-stage structure (major alloy) · Descent-stage main structure (beams, decks, bulkheads)
Used in 2 partsOutrigger truss members and landing-gear struts (redesigned) · Gimbal ring and gimbal drive actuators
Used in 2 partsInsulation blanket core · Supercritical helium tank (cryogenic)
Used in 2 partsPrimary struts with crushable aluminum-honeycomb cartridge · Footpads (x4, aluminum honeycomb)
Used in 2 partsPlume-exposed shield areas · RCS plume deflector
Used in 2 partsDescent stage batteries (x5, silver-zinc) · Ascent stage batteries (x2, silver-zinc)
Used in 1 partCombustion chamber case (titanium alloy)
Used in 1 partAscent-stage cabin, midsection and aft equipment bay shell
Used in 1 partInsulation blanket inner and outer layers
Used in 1 partInner cabin window pane
Used in 1 partRadiation-cooled nozzle extension (columbium C-103)
Used in 1 partHatch seals (elastomeric silicone)
Used in 1 partShear-deck webs, interim fatigue fix
Used in 1 partAtmosphere revitalization section and lithium hydroxide canister
Used in 1 partPlume-exposed shield areas, underlayer
Used in 1 partBase heat shield (BHS) insulation
Used in 1 partCrew compartment deck Velcro pile
Used in 1 partAblative chamber liner
Used in 1 partInner window seal jacket
Used in 1 partOuter cabin window pane
Structural alloys, thermal shield layers and engine heat protection are stated in NASA TN D-7084 and TN D-6844. Propellant tank, ascent engine and landing-gear honeycomb materials are not stated in the sources read. Components, suppliers and links were added from public sources. A material is left blank where no source states it.
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Descent-stage main structure (beams, decks, bulkheads)“The material used in the construction of the descent stage is primarily 7075-T6 aluminum alloy.” | Aluminium 7075-T6aluminium-7075 | — | — |
| Descent-stage hot-area structure“Titanium is used where high temperatures are experienced.” | Titaniumtitanium | — | — |
| Outrigger truss members and landing-gear struts (redesigned)“all struts except the outriggers were redesigned to the 7075-T73 condition” | Aluminium 7075-T73aluminium-7075-t73 | — | — |
| Shear-deck webs, interim fatigue fix“a fiber-glass "picture frame" was applied to each panel of the shear deck” | Fibre-glass clothfiberglass-cloth | — | — |
| Landing-gear energy absorbers“A honeycomb cartridge that fits in the two cylinders provides 9500 pounds of compression stroking at touchdown.” | Not said | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Base heat shield (BHS) insulation“a composite of alternate layers of nickel foil and Fiberfrax supported by standoffs attached to the titanium BHS structure” | Nickel foil and Fiberfrax (alternating layers)nickel-foil-fiberfrax-composite | — | — |
| Base heat shield support structure“attached to the titanium BHS structure” | Titaniumtitanium | — | — |
| Engine compartment blast shield“A specially shaped blast shield of Teflon-coated titanium is secured to the upper edge of the engine compartment” | Teflon-coated titaniumtitanium | Teflon coating | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Insulation blanket core“25 layers of 1/8-mil aluminized polyester film encapsulated in inner and outer 1/2-mil layers of aluminized polyimide film” | Aluminized polyester film (Mylar)aluminised-polyester-mylar | — | — |
| Insulation blanket inner and outer layers“inner and outer 1/2-mil layers of aluminized polyimide film” | Aluminized polyimide film (H-film / Kapton)aluminised-polyimide-h-film | — | — |
| Micrometeoroid shield“an outer micrometeoroid shield of aluminum” | aluminium (alloy not stated)aluminium | — | — |
| Plume-exposed shield areas“substituting layers of polyimide film, nickel foil, Inconel mesh, and Inconel foil” | Inconel foil and Inconel meshinconel | — | — |
| Plume-exposed shield areas, underlayer“substituting layers of polyimide film, nickel foil, Inconel mesh, and Inconel foil” | Nickel foilnickel-foil | — | — |
| RCS plume deflector“The deflector is constructed of Inconel, Inconel mesh, and nickel foil.” | Inconel, Inconel mesh and nickel foilinconel | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Control and display panelsPanels from which either astronaut can control and monitor every subsystem and fly the LM“Control and display panels contained everything necessary to control and monitor subsystem performance.” | Not said | — | — |
| Flight stations: attitude and thrust/translation controllers with adjustable armrestsHand controllers at each flight station for rotation and translation“Each flight station has an attitude controller, a thrust/translation controller, and adjustable armrests.” | Not said | — | — |
| Window heaters and shadesElectric heaters keep the windows from fogging; a shade with antireflective coating covers each window“All three windows were electrically heated to prevent fogging.” | Not said | — | — |
| Forward hatchHatch in the front face used to go between the cabin and the lunar surface or for EVA while docked“The forward hatch was in the front face assembly, just below the lower display panels.” | Not said | — | — |
| Overhead (docking) hatchHatch at the top of the midsection that gives access to the docking tunnel and the command module“The 33" overhead hatch was at the top midsection centerline.” | Not said | — | — |
| Hatch seals (elastomeric silicone)Preloaded seals in the hatch frames that the hatch lip presses into for a pressure-tight fit“A preloaded elastomeric silicone seal was mounted in the hatch frame structure.” | Elastomeric silicone compoundelastomeric-silicone-seal | — | — |
| Docking tunnel and ringStructural passage between the LM and the command module, topped by a docking ring“The docking tunnel, immediately above the overhead hatch, provided a structural interface between the LM and the CSM” | Not said | — | — |
| Docking drogueCone in the LM tunnel that receives the CSM docking probe for soft capture“The drogue, a portion of the docking mechanism, was secured below the ring to three mounts in the LM tunnel” | Not said | — | — |
| Crew compartment deck Velcro pileHooked boot soles grip the pile to hold the crew to the deck in zero gravity“covered with nonflammable Velcro pile that interfaced with hooked Velcro on the astronauts' boot soles” | Nonflammable Velcro pilevelcro | — | — |
| MidsectionWalk-through space aft of the crew compartment that houses the ascent engine and ECS components“The midsection housed the ascent engine, part of which protruded up through the lower deck.” | Not said | — | — |
| Aft equipment bay and equipment rackUnpressurized bay with electronics on a water-glycol cold-rail rack, plus gas tanks“The unpressurized aft equipment bay was formed by the aft midsection bulkhead and the equipment rack” | Not said | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Modularized equipment stowage assembly (MESA)Descent stage quad that carries television equipment, lunar sample stowage and PLSS components“Quad No. 4 housed the modularized equipment stowage assembly (MESA), which consisted of television equipment, lunar sample stowage, and PLSS components.” | Not said | — | — |
| Quad 3 pallets: lunar roving vehicle and Lunar Retro-Ranging ReflectorDescent stage quad that stowed the rover on the later J missions and the laser reflector“The quad No. 3 contained the lunar roving vehicle (LRV) and the Lunar Retro-Ranging Reflector.” | Not said | — | — |
| Interstage fittings (x4)Join the ascent and descent stages; severed explosively at staging“The LM ascent and descent stages were joined by four interstage fittings that were explosively severed at staging.” | Not said | — | — |
| Explosive devices (cartridges, nuts and bolts, cable guillotine)Fire to pressurize tanks, deploy the landing gear, vent the tanks and separate the stages“Electro-chemical explosive devices were operated by the astronauts to pressurize the propellant tanks, separate the ascent and descent stages” | Not said | — | — |
| SLA attachment pads and explosive tiedown strapsOutrigger apex pads that mate with the adapter fittings and are released after docking“Pads at the descent stage outrigger apexes mated with the SLA attachment fittings.” | Not said | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Landing gear assemblies (x4, cantilever)Four legs that absorb landing impact and support the LM on the surface“The cantilever landing gear consists of four assemblies, each connected to an outrigger that extends from the ends of the structural parallel beams.” | Not said | — | — |
| Primary struts with crushable aluminum-honeycomb cartridgePiston-cylinder strut whose honeycomb cartridge crushes to absorb the landing“by a crushable aluminum-honeycomb cartridge in each strut” | Aluminum honeycomb (alloy not stated)aluminium-honeycomb | — | — |
| Footpads (x4, aluminum honeycomb)37 in diameter pads that limit sinking into low-strength soil“is aluminum-honeycomb; its diameter is 37 inches. This large diameter ensures minimal penetration of the LM” | Aluminum honeycomb (alloy not stated)aluminium-honeycomb | — | — |
| Lunar surface sensing probes (x3)Contact probes about 5 ft below the footpads that tell the crew to shut down the descent engine“The lunar surface sensing probe attached to each landing gear footpad, except the forward one, is an electromechanical device.” | Not said | — | — |
| Uplock assemblies (x4) with detonator cartridgesExplosive-severed straps that hold the legs retracted until deployment in lunar orbit“One uplock assembly is attached to each landing gear assembly.” | Not said | — | — |
| Ladder and external platformNine-rung ladder on the forward leg and a platform below the forward hatch for access to the surface“The ladder affixed to the primary strut of the forward landing gear assembly has nine rungs between two railings.” | Not said | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Descent engine (TRW Lunar Module Descent Engine, LMDE)Throttleable, gimbaled engine that brakes the LM from lunar orbit, lands it and can hover“The TRW Lunar Module Descent Engine (LMDE, VTR-10) was a pressure-fed, variable thrust, gimbaling, liquid-propellant rocket engine with a 9,850 lbT maximum nominal thrust.” | Not said | — | Supplier: TRW (Space Technology Laboratories) |
| Variable-area pintle injectorSleeve-controlled injector whose area changes with thrust to keep combustion stable“The variable-area injector consisted of a pintle assembly, drive assembly, and manifold assembly.” | Not said | — | — |
| Cavitating venturi flow control valvesMechanically linked valves that meter fuel and oxidizer flow to set thrust“The flow control valves were non-redundant cavitating venturis with movable pintle sleeves.” | Not said | — | — |
| Combustion chamber case (titanium alloy)Titanium case around the ablative liner, welded to the exit cone at the throat“The engine chamber and exit cone portions were machined from 6A1-4V titanium alloy forgings and welded into one unit at the throat centerline.” | 6Al-4V titanium alloy forgings (printed '6A1-4V')titanium-6al-4v | — | — |
| Ablative chamber linerComposite ablative heat sink that keeps the case near 800 F“The selected configuration consisted of a high density, erosion-resistant silica cloth/phenolic material surrounded by a lightweight needle-felted silica mat/phenolic insulation.” | Silica cloth/phenolic ablative with needle-felted silica mat/phenolic insulationsilica-phenolic-ablative | — | — |
| Radiation-cooled nozzle extension (columbium C-103)Thin, crushable nozzle skirt from the 16:1 area ratio to 47.5:1“Columbium alloy C-103 was selected as the nozzle extension material because of its high-temperature (2,700°F) structural properties.” | Columbium (niobium) alloy C-103 with an aluminide coatingcolumbium-alloy-c-103 | — | Supplier: Wah Chang Company |
| Throttle valve actuatorElectromechanical servo actuator that moves the throttle linkage on command“The throttle valve actuator, built by Bendix Commercial Vehicle Systems, was a linear-motion electromechanical servo actuator that moved the throttle linkage” | Not said | — | Supplier: Bendix Commercial Vehicle Systems |
| Gimbal ring and gimbal drive actuatorsFrame and two actuators that tilt the engine through the center of gravity“The gimbal assembly was a rectangular frame composed of four beams with a modified I section machined from 7075-T73 aluminum alloy.” | 7075-T73 aluminum alloyaluminium-7075-t73 | — | Supplier: AiResearch Manufacturing Co. of Los Angeles (gimbal drive actuators) |
| Descent propellant tanks (x4, titanium)Four tanks, two fuel and two oxidizer, feeding the descent engine“The DPS propellant supply was contained in four cylindrical, hemispherical-ended titanium tanks of identical construction” | Titanium (alloy not stated)titanium | — | Supplier: General Motors Allison Division (initial); Sargent Industries Airite Division (later) |
| Supercritical helium tank (cryogenic)Double-walled tank of supercritical helium that pressurizes the descent propellant tanks“The double-walled supercritical helium tank consisted of an inner spherical tank and an outer jacket.” | Aluminized Mylar insulation in the vacuum space between tank and jacketaluminised-polyester-mylar | — | Supplier: Garrett Corporation AiResearch Manufacturing Company |
| Propellant quantity gauging system (PQGS)Four probes and a control unit that show remaining fuel and oxidizer and give a low-level warning“A propellant quantity gauging system (PQGS) enabled astronauts to monitor propellants remaining quantities in the four DPS tanks.” | Not said | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Ascent engine (Lunar Module Ascent Engine, LMAE, RS-1801)Fixed-thrust restartable engine that lifts the ascent stage off the Moon“The Lunar Module Ascent Engine (LMAE, RS-1801) provided the astronauts' only escape from the lunar surface.” | Not said | — | Supplier: Rocketdyne Division of North American Rockwell (injector, final assembly); Bell Aerosystems (valves, thrust chamber) |
| Ascent engine injector (Rocketdyne)Baffled flat-faced multi-ring injector with acoustic cavities that cured combustion instability“Rocketdyne's new injector design was a baffled, flat-faced, multi-ring unit with integral propellant-distribution manifolding and acoustic cavities.” | Not said | — | Supplier: Rocketdyne Division of North American Rockwell |
| Ascent engine ablative chamber and nozzle extensionPlastic ablative assembly that cools the chamber and the nozzle out to a 45.6:1 area ratio“The combustion chamber assembly consisted of the engine case and mount assembly and an ablative material (plastic) assembly, which included the nozzle extension.” | Not said | — | Supplier: Bell Aerosystems |
| Ascent engine bipropellant valve packageFour series-parallel valve assemblies giving redundant start and stop“The four individual bipropellant valve assemblies that made up the bipropellant valve package were arranged in a series-parallel arrangement” | Not said | — | — |
| Ascent propellant tanks (x2, spherical titanium)One fuel tank and one oxidizer tank for the ascent engine, linked to the RCS“The propellant supply was contained in two spherical titanium tanks.” | Titanium (alloy not stated)titanium | — | Supplier: Aerojet General Corporation, Downey plant |
| Ascent helium tanks (x2)Ambient-temperature helium that pressurizes the ascent propellant tanks“which was stored in two identical tanks that were made by Sargent Industries, Airite Division, El Segundo, California” | Not said | — | Supplier: Sargent Industries Airite Division |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| RCS thrusters (x16, Marquardt R-4D)Four clusters of four 100 lbf thrusters for attitude, translation, ullage and docking“The R-4D RCS thrusters, supplied by the Marquardt Corporation of Van Nuys, California” | Not said | — | Supplier: The Marquardt Corporation |
| RCS cluster frames and thermal shields (x4)Aluminum cluster casting holding four thrusters, heater elements and plumbing“The frame was an aluminum-alloy casting, shaped like a hollow cylinder, to which the four thrusters were attached” | Aluminum alloy casting (alloy not stated)aluminium | — | — |
| RCS propellant tanks with flexible bladdersTwo fuel and two oxidizer tanks in systems A and B that expel propellant under zero gravity“Fuel and oxidizer were contained within flexible propellant tank bladders.” | Not said | — | Supplier: Bell Aerosystems (tanks purchased by Grumman) |
| RCS helium tanks and isolation valvesHelium supply, sealed by redundant explosive valves until the astronauts prepare the RCS“The helium tank outlet was sealed by parallel-connected, redundant helium-isolation explosive valves” | Not said | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Inertial measurement unit (IMU) and inertial subsectionPrimary LM inertial sensor measuring attitude and acceleration“The IMU, which continuously measured attitude and acceleration, was the primary LM inertial sensing device.” | Not said | — | — |
| Navigation baseLightweight mount that holds the IMU, optical telescope and abort sensor assembly in alignment“The navigation base was a lightweight (~ 3 lb) mount that supported, in accurate alignment, the IMU, AOT, and an abort sensor assembly (ASA).” | Not said | — | — |
| Alignment optical telescope (AOT)Sighting telescope used to align the inertial platform on stars“The AOT and a computer control and reticle dimmer (CCRD) assembly comprised the OSS.” | Not said | — | — |
| Lunar module guidance computer (LGC, Block II Apollo Guidance Computer)Digital computer that aligns the platform, runs guidance and commands engines, radars and RCS“The Block II AGCs became known as the command module computer (CMC) and lunar module guidance computer (LGC).” | Not said | — | Supplier: MIT Instrumentation Laboratory (design) |
| Display and keyboard (DSKY)Astronaut interface to the LGC, on panel 4 above the forward hatch“The DSKY allowed the astronaut to load information into the LGC, retrieve and display information contained in the LGC” | Not said | — | — |
| Abort guidance section (ASA, AEA, DEDA)Strapped-down backup guidance for aborts: sensor assembly, 4,096-word computer and data entry panel“The AGS consisted of an abort sensor assembly (ASA), abort electronics assembly (AEA), and a data entry and display assembly (DEDA).” | Not said | — | — |
| Control electronics section (CES)Analog autopilot and attitude/translation control electronics tying controllers to the thrusters“Functionally, this equipment was contained in a primary guidance and navigation section (PGNS), an abort guidance section (AGS), and a control electronics section (CES).” | Not said | — | — |
| Landing radarFour-beam radar on the descent stage giving altitude and velocity during descent“The landing radar (LR), located on the descent stage, provided altitude and velocity data during lunar descent.” | Not said | — | — |
| Rendezvous radarAscent-stage radar that tracks the CSM transponder for rendezvous and docking“The rendezvous radar, which operated in conjunction with a CSM transponder, acquired and tracked the CSM before and during rendezvous and docking.” | Not said | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Atmosphere revitalization section and lithium hydroxide canisterRemoves CO2, odors, particulates and excess water vapor and controls cabin and suit temperature“Atmosphere revitalization section (ARS), which removed CO2, odors, particulates and excess water vapor from the oxygen environment” | Lithium hydroxide (spare canister and PLSS cartridge)lithium-hydroxide | — | Supplier: Hamilton Standard Division of United Aircraft Corporation (ECS subcontractor) |
| Oxygen supply and cabin pressure control section (four oxygen tanks)Stores gaseous oxygen for the atmosphere section; two descent-stage and two ascent-stage tanks“Two descent stage oxygen tanks provided oxygen during descent and lunar stay.” | Not said | — | Supplier: Hamilton Standard Division of United Aircraft Corporation (ECS subcontractor) |
| Water management sectionSupplies water for drinking, cooling, fire fighting and food, and refills the PLSS cooling tank“The water management section (WMS) supplied water for drinking, cooling, fire extinguishing, food preparation” | Not said | — | Supplier: Hamilton Standard Division of United Aircraft Corporation (ECS subcontractor) |
| Heat transport section and sublimators (x2)Water-glycol loops carry heat to two sublimators that reject it to space“The waste heat was rejected by two sublimators and transferred overboard.” | Not said | — | Supplier: Hamilton Standard Division of United Aircraft Corporation (ECS subcontractor) |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Descent stage batteries (x5, silver-zinc)Primary power from T-30 minutes; paralleled with the ascent batteries for powered descent“Each of the five identical descent stage batteries was composed of silver-zinc plates with a potassium hydroxide electrolyte.” | Silver-zinc plates with potassium hydroxide electrolytesilver-zinc-battery | — | Supplier: Eagle-Picher Company |
| Ascent stage batteries (x2, silver-zinc)Independent batteries enabled before lunar liftoff“The two identical silver-zinc batteries resided in the ascent stage.” | Silver-zincsilver-zinc-battery | — | Supplier: Eagle-Picher Company |
| 400 Hz inverters (x2)Redundant 115 VAC supplies from 28 VDC“Two identical redundant 400-Hz inverters individually supplied the primary LM AC power.” | Not said | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| S-band steerable and VHF in-flight antennasAntennas on the ascent stage midsection structure for Earth and command module links“S-band steerable and VHF in-flight antennas” | Not said | — | — |
Alloys for tanks (descent and ascent propellant, oxygen, helium), landing-gear honeycomb cartridges, the cabin pressure hatch and the ascent/descent engines were not found in the sources read. 2014-series alloy was not found. The Kapton grade is given only as 'polyimide film (H-film)'. Layer counts differ between LM units and sources; the 25-layer blanket is the 'basic design' per TN D-6844. Quotes from OCR text of the NASA PDFs, with OCR spacing corrected. Mass is for Apollo 11 LM-5 only; later J-mission LMs were heavier (not checked). More detail: Not found in public sources that could be fetched: the manufacturers of the lunar module guidance computer, abort guidance system, landing radar and rendezvous radar (secondary sources name TRW for the abort guidance system and Raytheon for the computer, but no primary page with a quotable statement was reached), the S-band and VHF antenna makers, the waste-management and window-heater hardware, and the builders of the landing gear struts and footpads. Materials stated only for the parts listed: titanium propellant tanks, 6Al-4V titanium and silica-phenolic descent engine chamber, columbium C-103 nozzle, 7075-T73 gimbal frame, aluminum-honeycomb strut cartridges and footpads, aluminized Mylar helium-tank insulation, Velcro deck pile, silicone hatch seals and silver-zinc batteries; thruster body, ascent engine chamber and tank alloys are not given. Tank, hatch and radar quotes from the Grumman Apollo News Reference (LM04) and NASA SP-4205 are taken from Wayback Machine copies of hq.nasa.gov pages because the ALSJ PDFs now return 404; the enginehistory.org series (Part 9.40 to 9.46) is a secondary compilation of Grumman manuals and NASA Apollo Experience Reports that I used for most numbers. enginehistory.org lists a gross LM weight of 46,100 lb in its particulars table, which does not agree with its own stage figures or the Apollo News Reference (about 36,100 lb); only the News Reference value is given. The descent engine maximum thrust appears as 9,850 lbf (enginehistory.org), 9,870 lbf (NASA SP-4205) and 10,500 lbf at full throttle in vacuum (enginehistory.org table); all are listed. No fetched source ties the A7L suit name to the lunar module, so no relation to nasa-apollo-a7l-spacesuit is given. The Apollo 11 Press Kit and Apollo Experience Report PDFs for the LM propulsion systems were not reachable as clean text, and the web search budget ran out before NASM object pages could be checked.
Collected from public pages and documents, checked 4 Nov 2026.
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