Aviation Week reports that the Ares V rocket isn’t powerful enough to launch a human mission to the moon as currently designed. Ares V’s capacity is about 11-12 tones below the 75.1 metric tons (with margins) that it needs to launch into trans-lunar injection. It is several tons short without margins.
“The payload requirements are very driving and very difficult to get to, and frankly our vehicle today is close but doesn’t quite meet those mission requirements,” said Phil Sumrall, advanced planning manager in the Exploration Launch Projects Office at Marshall Space Flight Center.
Current plans are for the Ares V to launch the Altair lunar lander, followed by the liftoff of the smaller Ares I with a four-member crew in the Orion spacecraft. The crew would spent four days in low Earth orbit before heading off to the moon.
NASA is working to boost the Ares V’s capacity as well as shaving about three tons off the Altair lander. In another article, Aviation Week reports the space agency has an in-house design team working on a rough concept for Altair. The team will be joined by some industry partners which will help develop a “minimal functional” design.
For more detailed information about the Altair design process, you can also check out this NASASpaceFlight.com article.