Konnichi Wa, Kibo
The International Space Station says hello to its newest addition, made in Japan.
- By Dan Barry
- Air & Space magazine, May 2008
(Page 4 of 5)
Over the course of many hours, Test Subject 1 and I tried every single bolt, nut, and fixture in the module. The vast majority were absolutely fine, better than most space hardware I have inspected. But every once in a while, Test Subject 1 would fit a tool and hand it to me, and I would have trouble making it fit. The offending fixture was duly noted and marked for repair. In the end, everyone agreed the test was a resounding success.
When I returned to Tsukuba, I asked about the policy of allowing contractors to do their own inspections, and was assured that space agency personnel would conduct a complete inspection once the module arrived at the research center. Of course, repairs would be more troublesome at that point than when Kibo was still at the factory, but to do otherwise could insult the contractor. As for me, at least I had made things less tense. The Japanese could consider the flaws that I found just overzealous pickiness by the NASA guy. And, even though repairing them really was required, it could be construed as a favor, not a reflection of deficient manufacturing.
None of this is meant as a criticism of Japanese space engineering. In fact, JAXA and its predecessor agencies have a solid record of successes, going back to the 1970s, in launching spacecraft for astronomy, solar physics, and Earth observation. But the switch from building satellites to building hardware for human spaceflight, with its more stringent safety requirements and need for tight coordination, is difficult for any nation, including the United States and Russia, which, nearly 50 years after their first spaceflights, still make the occasional mistake. And Japan has proven no exception.
My own shuttle mission, STS-72, offered a small example. While the Space Flyer Unit was a remarkable satellite and ultimately a success, it did have glitches. The first hint of trouble came when its solar arrays jammed while retracting. We had to jettison them, which took valuable time; the satellite could last only about an hour on battery power after the arrays were shut down. Without power, the onboard heaters would fail, causing the satellite's propellant lines to freeze and rupture. We couldn't bring a propellant-spilling satellite into the shuttle's bay; we'd have to abandon it.
Koichi Wakata had the job of using the shuttle's robot arm to bring the spacecraft into the cargo bay. All was going well until the last step, when the satellite wouldn't engage the locking latches. We could get two or three to lock, but not the required four. As he tried over and over, Koichi was the picture of cool concentration—no panic in that guy. But time was running out. Finally, with just five minutes of battery life remaining, he turned to us and said, "Here goes a slam dunk; be ready with those latches!" He revved up the arm and brought the satellite down like Karl Malone going to the basket. Sure enough, four latch lights lit, and we returned the satellite safely to Earth.
What had gone wrong? We never found out for sure. Most likely, a combination of weightlessness and exposure to the hot-cold cycles of space had slightly warped the satellite frame. We were lucky the warping was within the margins of what the latches could accommodate. It was another lesson in the complexities of space hardware, which—especially on large projects—often has to fit parts fabricated in different places at different times.
Nowhere is this more true than on the space station, the largest orbital construction project in history. The station's pieces were built in multiple countries, and the assembly will take more than a decade. New modules like Kibo and Europe's Columbus have to attach to U.S. and Russian modules that have been in space for years. To complicate things more, the station is pressurized, and adding or removing air can change the shape and stiffness of the modules, which have a hull thickness of just 1/16 of an inch. All of these factors raise the same concerns about hardware compatibility we had experienced with Japan's Space Flyer Unit.
Japan finds itself playing a different role than it did on past shuttle flights. Even when the science experiments were Japanese, the vehicle—and the overall mission responsibility—were NASA's. Now, as a full partner in the station program, JAXA will control Kibo from the Tsukuba Space Center in Japan, just as NASA controls its segment from Houston, Russia controls its segment from Moscow, and Europe runs the Columbus module from outside Munich. With the lives of astronauts at stake, decisions will have to be made jointly, but quickly and efficiently. On the first Japanese assembly flight, Mayumi Matsuura will be in Tsukuba as the lead flight director for Kibo. "This is the first time for us to deal with minute-by-minute operations on a daily basis," she says.