572. Apollo 9: Spacesuits

Left photo, the first American spacewalk using an umbilicus. Middle photo, the inner layer of a moon rated suit. Right photo, same suit with outer layer, visor, and backpack.

If you have not been following these Apollo posts, here is a quick summary: when three astronauts died on the launch pad, their scheduled flight was renamed Apollo 1. The flight which completed their mission, after much delay, was called Apollo 7 following the original sequence. Apollo’s “2 through 6” never existed.

The next flight, originally Apollo 8, was to be a repeat of 7, but was changed to be the first launch of the complete Apollo package, Control Module, Support Module, and Lunar Module. However, delays in building the LM (or LEM as it was called in the early days) meant that flight could not happen by the scheduled date. The Apollo 8 which actually flew was a different Saturn, different CSM without an LM and different crew. They <flew around the moon>.

The first flight with all parts of the Apollo was pushed back, renumbered to Apollo 9, and flew fifty years ago yesterday, March 3, 1969. A full picture of the shuffling of missions and crews would take more words that even the geekiest reader could tolerate.

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Apollo 9 was the second manned flight atop a Saturn V, and the first to have both CSM and LM on board. Jim McDivitt was in command. David Scott was the CM pilot and Rusty Schweickart was the LM pilot. Don’t confuse him with Jack Swigert of Apollo 13.

There were two main objectives for the ten day mission. First was to test the ability of the astronauts to dock the CSM to the LM, to undock and fly the LM separately, both as a complete unit and the ascent stage alone, and to dock the ascent stage to the CSM once again. The second objective was to test out the first American space suit which was not tethered to its mother vehicle.

We will concentrate on the space suit today and look at the testing of the LM on Friday. That will be posted at 3 PM, PDT, fifty years to the minute from the first separation of the LM from its CSM.

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The space suits worn by both Americans and Russians had not allowed true freedom. Cooling, power, and life support gasses were never contained in the suits, but were sent to the suits by umbilical connections. As long as the crew was inside the vehicle, this posed no problem. The suits were deflated and for long periods of each mission, helmets and gloves were removed. During launch and return, the suits were again made air tight but were not inflated. There was no need. If the cabin had been breached during those maneuvers, the suits would have continued to provide life support.

I never seen it admitted, but clearly both NASA and the Russians were flirting with disaster through all those early flights. Let me explain.

When the first spacewalks (EVAs, extra vehicular activities) were made by Alexey Leonov and then Ed White, the space suits proved to massively restrict mobility. Leonov could barely get back into his vehicle because his suit had puffed up so much. Ed White only got back into Gemini IV with great difficulty and with the help of fellow astronaut Jim McDivitt.

You can imagine what would have happened on any early fight if there had been a hull breach during a reentry, and the pilot’s spacesuit had suddenly become stiff and unmanageable when every second was critical.

Small glitches kill pilots, as everyone in aeronautics knows.

Five missions after White’s EVA, Eugene Cernan nearly died during a spacewalk because his suit was so unmanageable. See  posts 295 and 296. It took three more EVAs on three missions by three additional astronauts until before spacewalks were brought under control.

All of these EVA’s, Russian and American, used umbilicals to provide life support and to tether astronauts to their vehicles. That was not going to work on the moon.

The development of a suit suitable for moonwalks took seven years. Pressurization, oxygen, and cooling were taken care of by an inner layer that rarely made it into photos. See the middle picture above. The outer layer was a laminate designed to resist abrasion, radiant heat, and micrometeorites. The backpack took the place of the umbilicus and provided power and oxygen.

Backpacks were first tested on Apollo 9 by McDivitt and Schweickart. David Scott performed a standup EVA — that is, he stood up in the open hatch of the CM — but he received life support through an umbilicus. This was the pattern for Apollos 9 through 17. The moon bound astronauts used backpacks, the CM pilot did not.

If the LM tested on Apollo 9 had worked, but the backpack hadn’t, Apollo 11 could still have landed on the moon, but Armstrong could not have left the Eagle to make “once small step . . .”

But it did work. The EVA was cut short by Schweickart’s space sickness, but the backpack worked fine.

more on Apollo 9 Friday

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