Technicians at NASA's Kennedy Space Center in Florida began
modifications to 34 support beams, called stringers, on space
shuttle Discovery's external fuel tank Tuesday. The procedure
involves fitting pieces of metal called radius blocks over the tops
of the stringers located at the external tank's thrust panel area
to increase the structural support of the stringers. The thrust
panel areas are located at the attachment points between the tank
and the solid rocket boosters, which see the most stress during the
flight into orbit. The work is expected to take about a week.
STS-133 External Fuel Tank
Teams also are scanning all the tank's stringers using a
backscatter device, which bounces radiation off the tank allowing
engineers to see below the foam insulation. Engineers at various
NASA centers continue to analyze testing and imaging data. Managers
will meet again Thursday to determine whether radius block
modifications are needed on the remaining stringers.
Repairs to four cracks on three stringers on the opposite side
of the tank from Discovery that were discovered on Dec. 29 began
Monday and are expected to be completed mid-week. The repairs are
similar to repairs made on cracks found on two stringers after
Discovery's Nov. 5 launch attempt.
Scanning The Main Fuel Tank
The next available launch date for Discovery's STS-133 mission
to the International Space Station remains Feb. 3 at the opening of
a window that extends through Feb. 10.