Then, Scott stood on top of the ascent engine cover and put his head outside.

They then performed the "fire in the hole" test and another ascent engine burn.

The raw thunder of the ascent engines was nerve-wracking.

"Engine off," Rick said, his eyes glued to the ascent engine fuel level.

A failure of the LM ascent engine would guarantee a critical mission failure.

Unfortunately, their LM ascent engine fails to fire.

Had this not worked, the Lunar Module circuitry could have been reconfigured to allow firing the ascent engine.

She felt as if she were falling, as if the ascent engine was going to drive her straight down into the unforgiving rocks.

A fictional Apollo 19 mission takes a disastrous turn when the LM ascent engine fails to fire.

The descent engine was not burning smoothly, and the ascent engine was having fabrication and welding difficulties.

The ascent engine was fired in abort mode, known as a "fire-in-the-hole" test, where it was lit simultaneously with jettison of the descent stage.

The LM orbit was not perfectly in the same plane as the CSM's, so another burn of the LM's ascent engine was required.

They also let him practice using the descent and ascent engines for emergency thrust, and after he wheedled with them for a few days they even let him practice landing.

Strapped to the central stem were other items, including the hydroponics cylinders and the several components of the lander: life system, tug engine, two descent stages and the ascent engine.

When ready to leave the Moon, the LM would separate the descent stage and fire the ascent engine to climb back into orbit, using the descent stage as a launch platform.

The ascent engine was a big cylinder between the slots where pilot and copilot stood, sort of like the way the engine in an older van stuck out between the driver and the passenger.

Embodying a pressure-fed fuel system using hypergolic (self-igniting) propellants, the ascent engine was fixed-thrust and nongimbaled, capable of lifting the ascent stage off the Moon or aborting a landing if necessary.

(If necessary, landing could have been aborted at almost any time by jettisoning the descent stage and firing the ascent engine to climb back into orbit for an emergency return to the CSM.)

The Apollo 5 mission tested the Lunar Module in a space environment, in particular its descent and ascent engine systems, and its ability to separate the ascent and descent stages.

Aldrin had accidentally snapped off the pin of the ascent engine arming switch with his backpack, and he'd had to poke a felt pen into the hole to arm the engines before he and Armstrong could leave the Moon.

"Green" propellants, such as use LOX/Liquid Methane CH, offer savings in both performance and safety over equivalently sized hypergolic propulsion systems in spacecraft applications such as ascent engines or service module engines.

Cernan has said he observed the horizon spinning 8 times over indicating 8 rolls of the spacecraft under ascent engine power and that while the incident was downplayed by NASA, the roll was just several revolutions from being unrecoverable.

During the spring of 1963, Grumman hired Bell to develop the Lunar Module ascent engine, on the assumption that Bell's experience in development of the Air Force Agena engine would be transferable to the Lunar Module requirements.

Grumman placed heavy emphasis upon high reliability through simplicity of design, and the ascent engine emerged as the least complicated of the three main engines in the Apollo space vehicle, including the LM descent and CSM service propulsion system engines.

The LM crew checked out their craft's radar and ascent engine, rode out a momentary gyration in the lunar lander's motion (due to a faulty switch setting), and surveyed the Apollo 11 landing site in the Sea of Tranquility.