NASA's launch team has reported that an engine cut-off (ECO) sensor on the hydrogen side of Space Shuttle Atlantis's external tank (ET) has failed and the Mission Management Team (MMT) is considering whether to launch with three sensors today or removing the ET's propellant and attempting to launch on Saturday 8 September.
In the meantime NASA is continuing to prepare for Atlantis's lift off at 1541GMT from Kennedy Space Center's (KSC) launch complex pad 39B. The ECO sensor detects the levels of propellant in the tank to ensure the Shuttle's main engines are shut down at the right time. Problems with ECO sensors have delayed launches in the past. Shuttle Discovery's mission STS-121 was delayed from May to July because a faulty ECO sensor had to be removed from the ET.
While the MMT determines whether Shuttle needs the ECO sensor the astronauts have already boarded the silver Astrovan that takes them on the 20min trip to launch pad 39B and to the White Room, located at the 195ft level of the pad. From the White Room the astronauts will enter Atlantis one by one and be strapped into their seats before going through final checks in preparation for lift off.
NASA's Freedom Star and Liberty Star recovery ships are now in position in the Atlantic Ocean. The ships retrieve the Shuttle's Solid Rocket Boosters (SRB) back to KSC after they separate from the Orbiter during ascent. The SRBs will then be refurbished and reused for other shuttle launches.
Source: FlightGlobal.com
