NASA suspicious of foam crack repair

HOUSTON – NASA is investigating whether repairs to a small crack in the foam on Discovery’s fuel tank may have caused a 1-pound section of the insulation to break off during liftoff, officials said late Friday.

The shallow crack – just six-tenths of an inch long and two-tenths of an inch wide – was sanded away at the Louisiana manufacturing plant before the tank was shipped to Cape Canaveral, Fla. No new foam was applied.

It’s a common repair procedure, NASA officials said.

The external fuel tank was redesigned following the 2003 Columbia tragedy, but no improvements were made to the area where the foam came loose. Lockheed Martin Corp. built the tank.

Among the theories being investigated: whether a mistake was made in the manual spraying of the foam, whether the new environmentally friendlier foam was defective, whether too many people handled the foam and tank, and whether the foam was damaged during the tank’s shipment to Florida.