The descent engine
My main descent engine was a deep-throttling, ablative rocket mounted on a gimbal beneath the descent stage. It could produce approximately 45,000 newtons of maximum thrust, or about 10,125 pounds-force. Deep throttling means the engine could vary its thrust over a wide range, helping the astronauts control their descent. The gimbal allowed the thrust direction to be adjusted.
What powered the engine?
- Aerozine 50 was the fuel.
- Nitrogen tetroxide was the oxidizer.
- The propellants were stored separately and combined in the engine to produce thrust.
How I sensed the ground
Contact probes extended below three landing footpads. When a probe touched the lunar surface, it provided a contact signal to the crew and helped Armstrong know when the spacecraft had reached the ground.
How I absorbed impact
My landing legs incorporated crushable aluminium honeycomb shock absorbers. During touchdown, the honeycomb could deform and absorb some landing energy. The footpads helped distribute my weight.
A soft landing is a controlled touchdown in which a spacecraft reduces its speed enough to reach the surface without a destructive impact. It does not mean zero impact; it means the impact is managed so the vehicle can survive.
Mission details are based on the NASA/NSSDCA Apollo 11 Lunar Module / EASEP record supplied for this project.