spacetoday.net: Fuel sensor glitch scrubs shuttle launch

Posted: Fri, Sep 8, 2006, 1:48 PM ET (1748 GMT)

A problem with a fuel sensor in the shuttle's external tank forced NASA to scrub Friday's scheduled launch of Atlantis, giving the space agency only one more chance to launch the shuttle before standing down at least until late this month. Several hours before Atlantis' scheduled 11:41 am EDT (1541 GMT) launch technicians discovered that one of four hydrogen fuel engine cutoff (ECO) sensors malfunctioned, giving an erroneous reading after the shuttle's external tank had been filled with propellant. Unable to resolve the problem, shuttle managers decided a little less than a hour before the scheduled launch time to scrub the launch and try again Saturday at 11:15 am EDT (1515 GMT). The ECO sensor problem is similar to one that developed during preparations for the launch of the STS-114 return to flight mission last summer. Saturday is the last chance to launch the shuttle before waiting until after a Russian Soyuz spacecraft completes its mission to the ISS. The next official launch window does not open until late October, although NASA officials have discussed changing lighting requirements for shuttle launches that would permit another launch attempt in late September or early October.