Friday, May 27, 2016

Bigelow Under Pressure

Click the arrow to listen to the May 27, 2016 teleconference with NASA and Bigelow Aerospace representatives.

Perhaps we had inflated expectations, hoping that the Bigelow BEAM would expand nominally as demonstrated in artists' concepts.

Pressurization halted yesterday after the prototype habitat stopped expanding. NASA and Bigelow managers chose to pause to examine data returned from the Bigelow Expandable Activity Module berthed at the International Space Station's Node 3.

During the night, the fabrics relaxed enough that BEAM continued to slowly expand on its own.

Today's teleconference participants said BEAM has been depressurized for now, reducing the air in the bladders between the layers of fabric. Because it's in a vacuum, BEAM is retaining its shape even though the bladders are nearly empty.

BEAM was delivered to NASA in March 2015. Slated for launch on the SpaceX Dragon CRS-8 mission in September 2015, the launch was delayed seven months due to the loss of the SpaceX-7 mission in June 2015. The next flight had to wait until SpaceX solved the cause of the accident.

No one anticipated BEAM remaining tightly packaged for over a year.

But because this is a test, in a sense that's good because it allows NASA and Bigelow to test the prototype for behavior under such conditions.

Telecon participants stated that “friction force between the fabrics” is considered the likely cause for the habitat's failure to properly expand, but they remain fully confident that expansion will be achieved.

Another reason to proceed slowly is that Bigelow is collecting data on how the pressurization places stress loads on Node 3 and the station.

During an April 11, 2016 media event, Robert Bigelow and United Launch Alliance CEO Tory Bruno discussed their intent to pursue a deal to attach the larger next-generation Bigelow B-330 to ISS in the 2020s for commercial use. Studying how BEAM impacts the station structure collects data for that future enterprise.

NASA media representative Dan Huot said at the end of the telecon that tomorrow's attempt will be telecast live on NASA TV, but the time is to be determined.

If this attempt fails, further efforts will be delayed for about a week as ISS crew members have other activities scheduled, some of which involve the Canadarm. BEAM's expansion could cause vibrations that affect the arm's performance.

NASA animation of BEAM berth and expansion. Video source: NASA Johnson YouTube channel.

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