METAL fatigue may have caused the fuel-line cracks that have grounded NASA’s entire space shuttle fleet, according to independent materials experts.
They say the parts of the orbiter’s fuel system that failed can’t withstand the high strains imposed by the super-cold liquid hydrogen fuel. If they’re right, the shuttles may be in for an expensive redesign, leading to more launch delays.
The first crack was discovered last week during routine checks on the shuttle Atlantis. Measuring just 8 millimetres long, it appeared in a thin metal collar called a flow liner. These liners are fixed inside pipes carrying the propellant.…
