First on the Moon by Rod Pyle

First on the Moon by Rod Pyle

Author:Rod Pyle [Pyle, Rod]
Language: eng
Format: epub
Publisher: Sterling


The Lunar Module was very lightly built—it was a study in form following function.

The thin panels on the backside of the Lunar Module’s upper stage were not structurally critical. They did, however, protect the delicate electronics and systems behind the crew cabin. This image, taken after landing, shows how thin they were.

Next to come under scrutiny were the seats. One of the engineers suggested that the astronauts did not need to sit down in the 1⁄6-g environment near the Moon; they could stand in the LM cabin during descent and liftoff from the Moon. This became even more practical when the window layout was altered—the new small, angled windows worked better when the astronauts could stand closer to them, looking down. So the seats were pulled from the LM, saving more weight.

The overall structure of the LM was then considered. The top stage needed to be pressurized, which would require a certain amount of intrinsic strength. But the bottom stage of the lander—the octagonal structure that carried the descent engine, fuel tanks, and landing legs—was a different matter. Showing once again that they were shedding much of their traditional thinking, the engineers removed the metal panels from the sides of the LM descent stage, replacing them with a blanket of multiple layers of Kapton® (a type of Mylar®) and other films and fabrics that would provide even better thermal protection than aluminum sheets. It would even serve as a good micrometeorite shield. This shaved off many more pounds.

Hundreds of other parts of the design were scrutinized. The pressurized cabin of the LM, if built the same way space capsules were, would be far too heavy. So the Grumman engineers thinned the metal for the hull to dangerous levels, then added back just enough to do the job. The result was a pressure hull that was in many places only about as thick as a soda can, and in other areas little thicker than three layers of aluminum foil. On Earth, a dropped screwdriver would likely puncture it. The astronauts swore that when it was pressurized, the hull puffed out, and they took to calling the LM the “aluminum balloon.” They were not far off.

Lightness was key to success. Consider the tyranny of the variables: Any weight added to the LM required that its fuel tanks had to be made larger, which made the craft heavier, which required larger fuel tanks, and so forth. Add to this that every pound of mass added to the LM resulted in adding 3 more pounds of fuel to the Saturn V. It quickly becomes a toxic feedback loop—the project soon felt like sharpening a pencil at both ends until one had nothing left to write with.



Download



Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.