Lunar Module

Ascent stage

Crew Compartement Interior

Midsection Interior

Descent stage structure

LM interface with SLA

LM reference data

LM docking with the CM detail

Description:

• The lunar module carried the astronauts to the moon′s surface. The module was 23 feet (7 m) tall and 14 feet (4 m) wide. It had two sections: the upper ascent stage and the lower ascent stage. The upper stage carried the crew, equipment, and an ascent rocket engine; the lower stage had the landing gear, lunar surface experiments, and the descent rocket engine. When the mission was over, the lower stage provided a launch platform and was left on the moon. The upper stage rendezvoused with the command module and was jettisoned after the astronauts were reunited.
• Developed to implement the 1962 lunar orbit rendezvous decision, the lunar module was a two stage, self-sufficient spacecraft built by Grumman. It was carried to the Moon attached to the command module docking port, with its powerful descent engine pointing forward. In this configuration, the LM descent engine could be fired as a back-up propulsion system to boost the Apollo-LM combination out of lunar orbit in the event the Apollo engine failed before the landing sequence.
• The LM stood on four cantilevered landing legs which looked insect-like while retracted during flight. Each of the four legs ended in a dish-shaped pod which Grumman had designed to support the vehicle on a variety of surfaces. One leg was equipped with a ladder. The landing legs were attached to the descent stage which carried a throttleable rocket engine. On the Moon, the descent stage served as a launching platform for the ascent stage, which consisted of a pressurized cabin, guidance and navigation systems, including radar altimeter and computer, and a throttleable rocket engine. While it was docked with Apollo, the crew entered or left it through a tunnel. On the Moon, crewmen depressurized the cabin, opened the hatch and climbed out on to a small "porch" and then down the descent stage ladder to the lunar surface.
• When the crew completed outside surface activites, they climbed back into the ascent stage, hoisted samples aboard with line and pulley, closed the hatch, re-pressurized the cabin and lifted off the descent stage by firing the ascent engine. The ascent stage would rendezvous and dock with the Apollo in lunar orbit. The crewmen and their samples would then transfer to the command module. After safely returning to Apollo, the ascent stage was jettisoned.
• The odd shape of this spacecraft was dictated by the fact that it operated only in airless space; it did not have to be streamlined in any way. Two flight stations, at which the astronauts stood with harness restraints, had display panels, armrests, controls and landing aids, two front windows, and an overhead docking window. The landing leg struts, released explosively, were extended by springs. The main struts were filled with crushable aluminum honeycomb for absorbing compressive loads. All except the forward one were fitted with 1.7 m long sensing probes which upon contact with the lunar surface signalled the crew to shut down the descent engine.

List of Lunar modules:

LUNAR MODULE SPECIFICATIONS

First flight: 22-Jan-1968; first manned flight 3-Mar-1969 (Apollo 9)
Last flight: 7-Dec-1972 (Apollo 17)
Number of manned flights: 9
Principal uses: manned lunar landing
Unit cost: $50.00 million
Crew size: 2
Overall length: 6.4 m
Maximum diameter: 4.3 m / 9.4 m (diagonally across landing legs)
Habitable volume: 4.5 m³
Total mass: 14,696 kg
Propellant mass: 10,523 kg total
Primary engine thrust: 44.0 kN
Main engine propellant: NTO/Aerozine-50
Total spacecraft delta v: 4,690 m/s
Power: batteries; 50.0 kW total
Contractor: Grumman Aerospace Corp.

(Weights are not typical for every mission)

ASCENT STAGE
The Lunar Module operated as a unit until the time of leaving the Moon when the ascent stage (which contained the crew) functioned as a separate spacecraft for rendezvous and docking with the Command Module. This section had a docking port for linking up with the command ship and crew transfer.
Crew size: 2
Length: 3.5 m
Maximum diameter: 4.3 m
Crew compartment: 2.35 m diameter x 1.07 m long
Habitable volume: 4.5 m³
Total mass: 4,547 kg
Crew mass: 144 kg
Propellant mass: 2,358 kg
Reaction control system
    thrusters: 16 x 445 N
    propellant: NTO/Aerozine-50
    specific impulse: 290 s
Ascent engine
    thrust: 15.57 kN
    propellant: NTO/Aerozine-50
    specific impulse: 311 s
    delta v: 2,220 m/s
Power: batteries; 17.0 kW, 800.0 Ah

DESCENT STAGE
Length: 2.8 m
Maximum diameter: 4.2 m / 9.4 m (diagonally across landing legs)
Total mass: 10,149 kg
Propellant mass: 8,165 kg
Descent engine
    thrust: throttleable 4.67-43.90 kN
    propellant: NTO/Aerozine-50
    specific impulse: 311 s
    delta v: 2,470 m/s
Power: batteries; 33.0 kW, 1600.0 Ah
Descent trajectory (min:s)
    00:00 - start descent; altitude 15.2 km, velocity 1,700 m/s, thrust 100%
    06:00 - throttle down; thrust 55%
    08:30 - pitchover; altitude 2.3 km
    12:30 - landing; velocity at touchdown 1 m/s

J-SERIES MODIFICATIONS
Descent Stage: Increased supplies of oxygen and water; extended electrical life. Quad 1 re-arranged to permit stowage of folded Lunar Roving Vehicle (LRV). Quad 4 - new 50 kg water tank, waste container and additional oxygen pressure tank and gaseous oxygen module replaces Modularised Equipment Stowage Assembly (MESA). A re-designed MESA is fitted outside Quad 4, includes tool pallet, sample containers, batteries for personnel life support systems, and cosmic ray detector. Four descent engine propellant tanks lengthened by 8.6 cm providing 521.5 kg extra fuel and oxidizer. Descent engine burned for longer period; combustion chamber modified to reduce erosion; expansion skirt modified.
Ascent Stage: New stowage for re-designed pressure suits of greater flexibility which had increased supplies of oxygen, water and electricity for extended EVAs. Plumbing added to waste container in descent stage.