MISSION MOON
Apollo 9 proves the long-troubled lunar module is up to the task
Our special anniversary coverage of the July 20, 1969, lunar landing continues today with a look at Apollo 9, which set the stage for the moon walk.
When NASA was told to go to the moon, time was its unyielding enemy. Every decision about how to do it had to be weighed against the clock.
The method it chose — a “lunar orbital rendezvous” — meant that half of the Apollo spacecraft would descend to the lunar surface and half would remain in orbit above. This technique promised quicker results, but there was one inescapable compromise. The only rocket that could be built in relatively short order, the Saturn V, had a diameter of about 20 feet near the top, where the spacecraft would sit. In other words, the portion that would leave Earth orbit had to be really small.
For Apollo’s command/service module, where the astronauts would live most of the time, the limitations were not such a big deal. But for the lunar module it was attached to, the challenge was enormous.
“There were no precedents for what we were doing,” Thomas J. Kelly, the so-called father of the lunar module, would recall later. “We were neither bound nor guided by precedent.”
Or much of anything else other than the extreme demands of the task — and an unhappy space agency. For a long time there was reason to doubt that Kelly and his company, Grumman Aerospace, could pull it off. Its talent at building airplanes didn’t seem to be translating to building spacecraft.
It wasn’t until March 1968 that astronauts finally sat on the launch pad at Kennedy Space Center, awaiting a mission that would determine whether America would land on the moon by President Kennedy’s original end-of-thedecade deadline.
Apollo 9 was first and foremost an Earth-orbit test of the lunar module, and the culmination of more than six years of non-stop work by Kelly and his team of engineers. Kelly helped write the detailed proposal that landed Grumman the contract, but he had no real sense of what the relatively small defense contractor was getting into. Because of the unique space environment, things worked differently than normal. Problems arose that never had before. And each one had to be fixed as they popped up — there could be no lengthy test period to refine the product.
The subchapter headings in Kelly’s retrospective book about building the lunar module offer a glimpse into the frustrations his team faced: Propulsion and Reaction Control System Leaks, Ascent Engine
Instability, Stress Corrosion, Battery Problems, Tank Failures. When NASA looked deeply at the first lunar module it received, the reaction was brutal. A supervisor screamed at Kelly and other Grumman representatives, calling the spacecraft “junk” and “garbage” unworthy of any agency contractor.
Tempers soon cooled, and Grumman overhauled its team and its methods. But the LM did not get much easier to produce. With virtually no margin of error, the fabrication process and the parts selected had to be revised again and again. The tiniest leak or slightest hint of a crack in a wire meant ripping stuff out and starting over, always with the clock ticking.
“The schedule pressure from NASA and our own upper management was unrelenting, yet we had not shown any ability to hold schedules … for more than a few days,” Kelly said. “(Everything was) being developed simultaneously and were encountering many problems. The result was confusion, frustration, and progress that was painfully slow.”
What engineers at Grumman ultimately came up with was an ungainly contraption that appeared awkward and, frankly, unfinished — like a jumble of parts that someone had put together in a garage. As Kelly himself observed, the module “looked like it had the mumps on one side.” In truth, of course, it was a marvel of engineering, with every part, piece, tank, circuit and system painstakingly designed and redesigned, tested and retested. Every possible ounce had been shaved off, so much so that the “walls” were paper thin. Ugly or not — one nickname was “Bug” — the only thing that mattered was whether it would work.
Starting on March 3, the task of Apollo 9 was to find out. For a week the trio of James McDivitt, Dave Scott and Rusty Schweickart had to demonstrate that they could decouple the two modules, turn them around, and then dock. Once that was done, they had to put the lander through its paces. No piece of equipment was more critical: Should it fail at any point for any reason, the consequences were unthinkable. Absolute reliability was not a goal but a demand.
NASA was excited. Officials could already taste the summer rendezvous with the moon, which meant that all eyes were on the funny-looking machine that had caused so much trouble and inspired so much abuse.
Liftoff was auspiciously smooth, and soon Apollo 9 was placed in the anticipated parking orbit. The first order of business was performing separation and docking of the two modules. That was accomplished within the first three hours. Once done, the astronauts had to show the spacecraft could be maneuvered with just the SPS engine on the service module. No problem.
Finally, the lunar module was separated from the Saturn rocket’s third-stage, which fired once more to put it on a path toward Earth and disintegration during atmospheric re-entry.
The next test came the following day. The lunar module, which had been christened Spider, fired its descent engine for six minutes after extending the legs, which locked smartly into place. But the most serious operations were scheduled for
the mission’s fifth day. The LM would separate from the command/service module and fly on its own.
The moment of truth had come for Kelly and some 7,000 Grumman engineers and technicians that had worked on the lunar module over the years. With its systems activated, Spider separated from the CSM, named Gumdrop, and slowly moved away. So far away, in fact, that the other craft could no longer be seen. The only issue was the failure of Spider’s tracking light, which never turned on.
After requisite flight maneuvers involving the descent engine, Schweickart and McDivitt split Spider in half, firing the ascent engine designed to take astronauts off the lunar surface and back to the CSM. For six hours the two men put Spider, or at least its remaining half, through its paces before returning to the CSM. Schweickart later called the LM “a great flying machine” and likened the ascent-only portion to a sports car or fighter jet, so responsive was it to the slightest movement of the controls.
“I could hardly believe that this agile machine, dancing so gracefully through space, was the same crotchety beast with the broken wires and structural cracks that had given us fits for over two years of ground testing,” Kelly recalled.
The remainder of the 10-day mission was devoted to a more leisurely testing of the command/service module, especially the SPS engine and the capsule’s thrusters. When Gumdrop finally headed back to Earth, splashing down in the Atlantic Ocean not far from Bermuda, NASA officials considered Apollo 9 an unqualified success. The lunar module was ready for business.
“It was a damned good mission with a great crew,” Flight Director Gene Kranz later said. “The LM rendezvous radar, computer, and propulsion systems passed every flight test. The mission … proved that the lunar module, in a zero-G environment, was a remarkably sturdy space buggy.”
Kranz also pointed out that the mission demonstrated how the LM could be used to get astronauts home should an emergency occur with the command/service module. Few, perhaps, thought that would ever be necessary. Then came Apollo 13.
But that was a long way off. Next up was the full-on dress rehearsal all the way to the moon. The lunar module, for all its grueling development, had done Grumman proud, just as the command/service module had for North American Aviation. Now it was time to put everything together once again and fly another half-million miles, putting the program and a nation now enthralled by it on the doorstep of a dream.
“There were no precedents for what we were doing. We were neither bound nor guided by precedent.”
— Thomas J. Kelly, executive at Grumman Aerospace and the so-called father of the lunar module