Ares I Rocket Passes Preliminary Design Review
Orion November Preliminary Design Review Delayed
The Ares I rocket that will power the next-generation Orion crew capsule into space passed its preliminary design review (PDR) with only a few outstanding issues still open, NASA leaders told journalists.
It was the first final PDR for developing a manned space vehicle in more than 35 years, since the program to produce the space shuttles.
Earlier Ares PDRs focused on individual segments of the rocket, while the PDR conference this week examined the overall rocket in entirety, determining that Ares meets requirements with acceptable risk, within cost and schedule constraints.
At the conclusion of the Ares rocket PDR conference, there was "a unanimous vote to proceed on to the critical design review," or CDR, by the 24 people with voting power, said Doug Cooke, deputy associate NASA administrator for the Exploration Systems Mission Directorate. This will involve years of producing detailed designs for components and sub- components of the rocket. The integrated CDR would aim for a March 2011 target.
Also briefing were Jeff Hanley, manager of the Constellation Program that is producing the next-generation U.S. spaceship system Orion-Ares, which will replace the current space shuttle fleet, and Steve Cook, the Ares project manager.
Various different segments of the Ares rocket involve separate efforts by The Boeing Co. [BA], ATK Techsystems Inc. [ATK], and Pratt & Whitney Rocketdyne, a unit of United Technologies Corp. [UTX].
The Orion development program, led by Lockheed Martin Corp. [LMT], was to have its PDR in November, but that now will be delayed because of a change in budget and schedule. So the PDR will be put off until some time in 2009, with an exact date to be determined in coming weeks.
Vibration problems, called thrust oscillation, are being resolved, briefers said. As earlier reported, NASA has a solution that will avoid putting heavy shock absorbers on seats in Orion, because that move would add enormous weight both to and from the moon. (Please see Space & Missile Defense Report, Monday, Aug. 25, 2008.) There will be a follow-up review, or "delta," review on thrust oscillation work next summer.
Thus far, the Ares effort is on schedule and under budget, they added, meaning Ares is still within its allocated budget, with a margin or cushion. The Ares and Orion efforts are part of the Constellation Program, which also will develop the Altair moon lander.
The aim is to have an unmanned Ares I-X flight next spring, and much later the first manned Orion-Ares flight to low Earth orbit in 2014, and then to go to the moon briefly by 2020. Later in that decade, the United States would establish a permanent manned outpost on the moon. And at some still-later time, the United States would go on to Mars and other solar system destinations.
Some issues that NASA experts and contractors are examining involve environmental concerns, such as the threat of hail, lightning or rain once the Ares rocket carrying Orion is rolled out to the launch pad and lifts off into clouds at Kennedy Space Center. Ares will be much more robust than the shuttles, briefers said, with decisions yet to be made as to whether Orion-Ares should be able to take a lightning strike without harm.
Other issues center on aerocoustics, or noise during flight, and pyro shock. That latter is the shock to the entire U.S. spaceship system when small explosive bolts are detonated to achieve results such as separation of one rocket stage from another.
The Ares development is proceeding well, briefers said, with thousands of pounds of weight margin to offset any weight gains as the rocket design work proceeds, briefers said.
Further, there are action plans to resolve each of the remaining issues, and those plans were deemed satisfactory in the latest PDR.