Weight constraints imposed by the Ares I crew launch vehicle, meeting safety and performance targets without significant cost growth, together with "the sheer integration of the job", are the major challenges Orion crew exploration vehicle prime contractor Lockheed Martin is wrestling with in developing NASA's first manned vehicle in 35 years.

Speaking at the Space Foundation National Space Symposium in Colorado Springs on 10 April, Lockheed Martin Space Systems human spaceflight vice-president and general manager John Karas described a rigorous, challenging process of design cycles, performance and weight trade-offs, requiring system selections to be completed by set milestones.

Karas says launch-vehicle performance is a major constraint on Orion weight growth. "The Ares I can only move so much. You've got to fit with that. It's about managing the [performance] requirements." He says the launch abort system also has a great bearing on Orion crew and service module mass.

The final trade-off studies under way focus on meeting crew safety and vehicle performance targets, without incurring significant cost growth, he says.

Source: Flight International