NASA Opts for ‘More Prudent Action’ : Leak Scrubs Launch of Weather Satellite

The launching of an unmanned Delta rocket carrying a weather satellite was scrubbed by NASA Thursday, after a small quantity of kerosene-type fuel was discovered leaking past a valve in the main engine system.

The launching, the first scheduled from the Cape Canaveral area since the ill-fated space shuttle Challenger exploded during its ascent Jan. 28, was postponed until Saturday, NASA spokesman George Diller said.

The delay was announced less than three hours before the scheduled 6:18 p.m. EDT liftoff of the three-stage Delta rocket at Cape Canaveral Air Force Station.

Diller said that engineers discovered the leak while going through standard test procedures. About a quarter-cup of RP1, a kerosene-type fuel used by the first-stage rocket, had leaked past a valve in the main engine.

Two subsequent checks failed to uncover any additional leakage, but the fuel lines must be flushed and purged before the flight can take place, Diller said.

The National Aeronautics and Space Administration has taken no chances with the Delta launch, looking on it as a means of restoring confidence in the nation’s space program after the Challenger disaster and the explosion of an unmanned Titan rocket at Vandenberg Air Force Base in California two weeks ago.

Diller said that NASA officials believed the flight would have been safe despite the leak, if the rocket had been launched as scheduled. But, he added: “The more prudent action was to go through and be sure those fuel lines are dry.”

The work of flushing and purging the fuel lines will begin today and the rocket is expected to be ready for launch at 6:18 p.m. Saturday--48 hours after the original liftoff time.

Diller said the weather forecast for Saturday is not as good as it was for Thursday. A front is moving in with clouds and rain showers, “but not enough to affect the launch,” he said.

The Delta rocket is scheduled to carry the GOES-7 weather satellite that is designed to fill a critical surveillance void during the coming hurricane season.

The satellite is to replace GOES-5, which lost its ability to transmit cloud pictures two years ago, cutting in half the nation’s weather watch capability from stationary orbit, 22,300 miles high.