It’s crunch time for commercial crew providers Boeing and SpaceX as the companies attempt to meet NASA’s safety requirement of one possible fatal accident in 270 flights.The space agency is planning a comprehensive safety review of the spacecraft next month.
But these commercial efforts face formidable obstacles in meeting safety requirements set by the National Aeronautics and Space Administration, posing policy and public-relations dilemmas for the agency’s chiefs.
Experts say NASA likely will require inspections in space to reduce the threat of catastrophic accidents, a last-ditch safeguard that it had hoped to avoid when approving the plan three years ago. Still, it is unclear is whether such on-orbit checks by NASA would alleviate dangers from space debris and tiny meteor fragments, say experts inside and outside the agency….
The commercial designers are seeking to alleviate other risks. They are concerned that extra shielding to better safeguard equipment and crews from collisions with debris could make spacecraft too heavy. They also are examining risks associated with vibrations during launch, explosives that deploy parachutes, vulnerabilities of heat shields and other issues.
But their biggest safety challenge stems from the thousands of tiny meteors or space particles now prevalent in space that can damage or penetrate the space capsules. Traveling at approximately 17,000 miles an hour, even a paint chip can spark disaster. Boeing partly addressed this by changing its design to install Kevlar backing. SpaceX is relying on other features.