Shuttle programme managers just announced that they are standing down for another 24 hours to review a problem with one of the orbiter’s three fuel cells.
The roughly 100kg fuel cells combine hydrogen and oxygen to create power for the shuttle and water for its crew. They are considered essential for shuttle operations, and Atlantis will not launch without all three in working order.
In fact, shuttle programme managers kept insisting, all three cells do appear to be working at the moment, but a cooling motor on one of cell is only partially operational. As is, it shouldn’t be a problem, but if anything else were to go wrong, it could create significant trouble that might cut short the mission.
Engineers will spend most of tomorrow looking at the history of the fuel cell to try and see if they can find the origin of the fault. That’s not easy, says shuttle programme manager Wayne Hale. The cell was built in 1976 and tested in 1981 by a company that has changed hands at least four times since then. And the circuitry is proprietary, says Hale, “which is to say that the vender sold us this thing but didn’t tell us exactly how it works.”
They’re now trying to resurrect those old proprietary drawings to learn exactly what caused the failure and whether it could worsen.