Orion PDR delay could stretch into 2010

by Chris Bergin

The requirement to carry out an additional Design Analysis Cycle (DAC) has already delayed Orion’s Preliminary Design Review (PDR) into the middle of next year.

However, a recent Constellation meeting noted the delay may reach into 2010, dependent on the progress with the additional DAC and associated technical challenges.

The Orion PDR was set to take place last Friday, before being initially delayed to November – via a CEV Project Control Board (CPCB) meeting back in May.

“The CPCB gave preliminary approval of schedule adjustments. A CR (Change Request) will be created after it is reviewed by Project Manager to track and receive formal project approval,” noted minutes from the meeting on L2.

“Also proposes to baseline the following changes: PDR moved to 11/21/08 (from 9/26/08), CDR (Critical Design Review) moved to April 2, 2010 (from 9/25/09), DCR moved to 3/15/13 (from 1/18/13). The CPCB concurred with the revised PDR schedule as presented.”

“The presentation was made in order to get Project approval of a six week slip in the PDR schedule, as well as inform the CPCB of remaining milestones on the schedule. The revised schedule presented moves PDR Board from 9/26/08 to 11/21/08.”

However, this date has slipped yet further, now noted to be August 21, 2009 – almost a full year slip to the original date, with February, 2010 mentioned as a potential date based on technical challenges and a mooted switch to composite materials for the Crew Module.

It is not yet confirmed if the references to composites are in relation to the recent NASA Engineering and Safety Center (NESC) driven evaluations into a fully composite Orion Crew Module, or specific areas of Orion. However, other issues are involved with the PDR slips – which are also likely to heavily impact Orion’s CDR date.

Orion has undergone numerous changes during its short design life, mostly via mass shedding directives sent up the stack due to Ares I performance issues. These constant changes were referenced by Orion’s contractor, Lockheed Martin, in reaction to further requirements surrounding the mitigation of Thrust Oscillation.

While the Crew Seat Isolation pallet – one of a couple of options available for Thrust Oscillation mitigation via Orion, in tandem with Ares I’s dual solutions – isn’t a major mass impart on the vehicle, its recent interference by the Ares I PDR hasn’t aided Lockheed’s design work.

Also, in reaction to NASA’s comment that the latest version of Orion (606C) by Lockheed Martin was not of the quality they had wished for, Lockheed Martin stressed these continued changes to the baseline of the vehicle are in part to blame.

“NASA has expressed concerns with 606C model and quality,” documentation noted. “Community must understand that there has not been two consecutive deliveries with the same baseline design, because (of) multiple configuration changes.”

Meanwhile, work is continuing at the Langley Research Center (LaRC) on the Orion Seat Pallet Test Article, which will be key element to both the Thrust Oscillation Crew Seat Isolators and the safety of the crew during splashdown.

Analysis has been taking place this month via dynamic testing in the Vertical Drop Tower at the Air Force Research Laboratory, at Wright-Patterson Air Force Base in Dayton, Ohio, while static tests for tension, compression and restroking are conducted at LaRC.

“Fabrication of the Crew Module Seat Pallet Test Article at Langley Research Center (LaRC),” noted information. “Energy absorbing struts for initial tests were received. A static test of a strut indicated the stroke versus load profile closely matches the specification with a uniform load of 8700 lb as compared to the 8500 lb requirement.”

Work is also progressing well on the Pathfinder Crew Modules, as preparations continue for the Pad and Ascent aborts.

“Random vibration testing of the Pad Abort-1 avionics Developmental Flight Instrumentation (DFI) Engineering Development Unit (EDU) pallet with the pallet pre-load fixture is complete,” added information on L2.

“Additional accomplishments include: Installation of the Crew Module microphone. Final Remote Data Acquisition Units (RDAU) were received at Orbital Dulles. All sensors and RDAU’s for the Launch Abort System were delivered. Center of gravity practice tests using the Crew Module mock-up are complete.

“Eight of the ten permanent skin panels on the Pathfinder Crew Module (CM) have been installed with permanent fasteners. The critical lift of the Ascent Abort-1 Heat Shield dish was performed to position it onto the tall stand located at the LaRC B1244/hangar. After leveling of the dish on the stand, internal structure installation will begin.”

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