The U.S. space agency plans to launch the shuttle Discovery next month, but some engineers feel it should wait until all safety concerns have been resolved.
The engineers want more changes to be made to the vehicle's fuel tank, reports USA Today. They are also concerned about tiny defects in some of its electronic boxes.
NASA shuttle program manager Wayne Hale was quoted as saying the section of foam on the tank most prone to causing damage to the shuttle has been removed. But, the report said, he agreed other foam from the tank could still be hazardous.
Some engineers had earlier said the National Aeronautics and Space Administration should redesign small foam features that plummet off the tank during liftoff.
Hale said NASA officials opted to fly the tank without redesigning the ramps because a tank renovation should be tested on its own during a flight before other changes are made.
Discovery's mission to test repair techniques and work on the International Space Station is scheduled to lift off between July 1 and July 19.
Copyright 2006 by United Press International
Explore further: It's 'full spin ahead' for NASA soil moisture mapper