The US Aerospace Safety Advisory Panel (ASAP) says that NASA's failure to commit the Space Shuttle officially to a career lasting another 20 to 30 years has exposed flightcrews "to higher levels of risk for longer than necessary" due to a lack of corresponding long-term safety upgrades for the orbiter fleet.
Short-term commitments to continue Shuttle operations, while follow-on second generation reusable launch vehicles (RLVs) are studied and new technologies developed, have resulted in NASA failing to commit the Shuttle to safety upgrades beyond those planned to take place by 2005.
Although the perceived operational timeline for a second generation RLV is being extended, the addition of safety systems to the Shuttle is not being accelerated. The VentureStar RLV, proposed in 1996, was to have been the Shuttle follow-on and should have flown in 2005, but it will take "10 years just to build a prototype", says ASAP.
During a five-year period when it was becoming obvious that the RLV programme was going to take much longer than anticipated, emphasis should have been placed on extending the Space Shuttle's operational requirements, particularly safety, suggests the panel.
ASAP says that NASA should commit the Shuttle and new safety features to a definite timetable that will allow developments to be implemented to fixed budgets and timescales.
"Sustained shortfalls in these resources will eventually compromise NASA's ability to carry out its challenging mission," says ASAP. "People in Congress and the former administration have not supported the continuation of the Shuttle beyond [an] arbitrary horizon," it adds.
Longer-term commitment to safety could see the development of a crew escape capsule or ejection seats and safer fly-back liquid propellant strap-on boosters.
It is estimated that the Space Shuttle fleet of four orbiters could fly at least 400 more missions.
Source: Flight International
