Evidence Cited That Lightning Hit Rocket

A pinpoint hole in a charred chunk of a failed satellite rocket is strong evidence that the vehicle was hit by lightning before it broke apart last week, the head of an investigation team said Friday.

Jon R. Busse said at a news conference that no conclusions had been reached, but he said electromagnetic interference remained the leading candidate.

Busse displayed the yard-square piece of rocket, describing the suspect area as a “pinhole in the fiberglass and cork section of the conical part of the nose fairing.”

The fairing, or nose cone, protected the $83-million military communications satellite that rode atop the $78-million Atlas-Centaur rocket, which broke apart 52 seconds after it was launched in a rainstorm on March 26.

100 Fragments Recovered

The fiberglass side of the recovered section was charred over an area about two inches in diameter. On the cork side, the pinhole is surrounded by another charred section about six inches long and two inches wide.

The quarter-inch-thick piece is among about 100 fragments of the rocket recovered either from the ocean or nearby beaches. Other pieces are being examined for evidence of a lightning strike.

Busse quoted lightning experts on his review panel as saying the burn was similar to those caused by lightning on fiberglass sections of aircraft. But he said they have not concluded whether the Atlas-Centaur fairing was charred before, during or after the accident.

Busse said it is possible that lightning struck the rocket after it broke apart, or possibly even before the start of the sequence of events that caused the failure.

“We don’t know when the pinhole occurred,” he said. “We can’t correlate this hole with the other things that were going on.”

Busse said on Monday that four lightning strikes were reported near the rising rocket about 48 seconds after liftoff and there was a strong indication that electro-magnetic interference was associated with the destruction.

Static Charge Lightning

Such interference could be caused by lightning or by static charge lightning induced by the rocket as it rose through the rain.

Although the rocket was launched in a driving rain with lightning flashing several miles away just before blastoff, the National Aeronautics and Space Administration launch director said the rocket was cleared for liftoff because all weather criteria had been met.

The failure drew criticism from several quarters, including Congress, where Sen. Ernest F. Hollings (D-S.C.), chairman of the Senate Commerce, Science and Transportation Committee, said the decision to launch “was crazy.”