NASA's safety chief and the agency's top engineer said today in a joint statement they did not oppose launching the shuttle Discovery July 1 despite serious concern about so-called ice-frost ramps on the ship's external fuel tank.

Discovery was cleared for launch Saturday after a two-day flight readiness review in which Bryan O'Connor, chief of Safety and Mission Assurance, and the agency's chief engineer, Chris Scolese, voted to delay launch until the ice-frost ramps could be redesigned.

NASA Administrator Mike Griffin said he did not agree that the ice-frost ramp foam posed a "probable/catastrophic" threat to the shuttle and cleared Discovery for flight. A "tiger team" of engineers is working on an ice-frost ramp redesign the agency hopes to implement within a few flights.

Griffin said even if ice-frost ramp foam did cause damage during Discovery's launching, it would not directly threaten the crew. In a worst-case scenario, which he views as extremely unlikely, the astronauts could either attempt repairs or move aboard the space station to await rescue by another shuttle crew.

O'Connor and Scolese said today in a statement that they agreed crew safety was not at issue.

"Crew safety is our first and most important concern," the statement said. "We believe that our crew can safely return from this mission.

"We both feel that there remain issues with the orbiter - there is the potential that foam may come off at time of launch. That's why we feel we should redesign the ice/frost ramp before we fly this mission. We do not feel, however, that these issues are a threat to safe return of the crew.

"We have openly discussed our position in the Flight Readiness Review - open communication is how we work at NASA. The Flight Readiness Review board and the administrator have heard all the different engineering positions, including ours, and have made an informed decision and the agency is accepting this risk with its eyes wide open."

See our earlier story for detailed coverage of Griffin's remarks and the decision to press head with launch on July 1.

Additional coverage for subscribers:
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      DIAL-UP: part 1 and part 2
      BROADBAND: part 1 and part 2
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