GAO finds risks in NASA program

The U.S. Government Accountability Office says it's found major risks to the successful development of NASA's replacement for the space shuttle.

The GAO, Congress' investigative arm, examined two components of the National Aeronautics and Space Administration's Constellation Program that's designed to send humans to the moon and Mars: the Ares I Crew Launch Vehicle, and the Orion Crew Exploration Vehicle.

NASA is scheduled to launch the program during 2015, five years after the Space Shuttle's last mission.

The GAO said it found Ares I, which will have a solid rocket booster for its first stage and a liquid-fueled second stage, risks excessive vibration during launch and excessive weight. The GAO also said it's not known how the fifth segment of the solid rocket's first stage will affect the vehicle's flight characteristics.

Federal investigators also reported existing NASA facilities are inadequate to test the new engine.

Additionally, they said the heat shield needed to allow the Orion vehicles to safely re-enter Earth's atmosphere is beyond the capabilities of current manufacturing processes.

The GAO concluded the space agency's capacity to meet production and budget goals is uncertain, partly because NASA is still defining many of the vehicles' performance requirements.