Shuttle Program Head Leaving NASA

NASA's most prominent voice in the days following the Columbia accident announced Wednesday he is leaving the space agency at the conclusion of the investigation into the loss of the shuttle.

Ron B. Dittemore, a 26-year veteran of NASA who served more than four years as head of the space shuttle program, said he plans to leave as soon as the agency appoints a new program chief and starts an orderly transition of leadership.

"My decision to leave the space shuttle program has been a very difficult one but is a decision I began struggling with long before the tragedy of the Columbia accident," he said. "The timing of my departure is based on when I believe will allow for the smoothest management transition possible as the pace of work to return the shuttle to flight begins to ramp out."

Dittemore said he made personal plans last summer to resign this spring and had discussed the plans with NASA top officials. But after Columbia came apart during its return to Earth on Feb. 1, "all personal plans had to take a back seat," he said Wednesday.

Michael Kostelnik, deputy associate administrator for the space shuttle, said the space shuttle program manager's job is a key position in the NASA. He said he is looking for candidates in the space agency, in other government agencies and in industry.

The Houston Chronicle reported that NASA's "short list" of candidates include James Halsell, an astronaut now leading the agency's return-to-flight efforts, as well as former astronauts Loren Shriver and Brewster Shaw. Kostelnik declined to discuss specific candidates.

Kostelnik praised the work of Dittemore, calling him "the voice of the program" during the days following the Columbia accident.

"A lot of the credit that NASA received for being forthcoming, we owe to Ron," he said.

But during the news conference, Dittemore declined to discuss some of his remarks made in the accident aftermath.

Dittemore provided detailed daily briefings after Columbia's loss, patiently and candidly answering questions as engineers investigated the accident. His plain talk contrasted with NASA's secretive, often hostile response to reporters after the 1986 Challenger explosion.

In February, NASA administrator Sean O'Keefe complimented Dittemore for doing an "amazing job."

At one point, Dittemore told reporters that there was little that could have been done for Columbia even if Mission Control had known the shuttle's left wing thermal shield was damaged. Administrator O'Keefe later disputed that view and said that Dittemore was not speaking for the agency. Dittemore on Wednesday declined to discuss that incident, but noted that there was no way for astronauts on Columbia to have repaired broken thermal tiles.

Kostelnik said that although NASA's goal is to resume space shuttle flights by November or December, just when the space fleet flies again will depend on the conclusions of the Columbia Accident Investigation Board.

The board has already made two recommendations, which Kostelnik said are being followed, but a final report is not expected until summer. Depending on what has to be fixed on the shuttle, he said it could be early next year before the spacecraft fleet is ready to fly again.

Board members have suggested that thermal protection tiles on Columbia's left wing were damaged when blocks of foam insulation peeled off a fuel tank and smashed into the wing's leading edge. Investigators have suggested this could eventually have caused a breach that allowed superheated air from the friction of re-entry to penetrate and destroy the internal aluminum structure of the wing.

Dittemore joined NASA's shuttle program as a propulsion systems engineer in 1977. He was selected in 1985 as a flight director and supervised 11 missions. He became shuttle program director in 1999.

By Paul Recer