marchand chronicles

Filling The Gaps

Houston, We're Fixing The Damn Problem

When the space shuttle Columbia lifted off in mid-January 2003, nobody suspected that the crew was already doomed. Insulation foam from the external tank detached during launch and struck tiles on the left wing of the shuttle. This irreperably compromised Columbia's ability to reenter Earth's atmosphere.

External tank insulation also fell off during the launch of Discovery. But because this mission has a thousand eyes on it all the time, NASA was quickly able to determine that the foam did not hit the shuttle. However, the insulation problem was what NASA spent the last 2½ years trying to fix, so they indefinitely grounded the rest of the fleet.


Discovery lifts off on July 26. (AP)

However, Mission Control soon discovered a new problem for Discovery: small "gap-fillers" in between the ceramic tiles on the underside of the ship near the nose cone were protruding from the shuttle. NASA frequently noted after a landing that sometimes these gap-fillers would stick out an inch or so from the belly of the craft. However, they'd never discovered this phenomenon while the ship was still in orbit.

These gap-fillers are only necessary for liftoff, to keep the tiles from colliding with each other during the incredible amount of vibration as the shuttle thrusts upwards. However, the small protrusions could affect Discovery's reentry.

So, being a clever and imaginative bunch, NASA ordered the astronauts to boldly go where no one has gone before: on a spacewalk under the shuttle. Early this morning, Mission Specialist Steve Robinson dangled from a robotic arm underneath Discovery's belly to pull out the gap fillers or, failing that, cut them off with a modified hacksaw.

It never came to that.


Steve Robinson maneuvers under Discovery to remove gap fillers early this morning. (AP/NASA)


Believe it or not, there's now yet another problem: part of Discovery's thermal insulation blanket is sticking out from below the pilot's window.


The thermal insulation blanket is protruding out more than 1½ feet. (Reuters/NASA)

Mission Control is postponing a decision about that until tomorrow. Discovery is set to land early Monday morning.

While the shuttle missions are not 100% safe, NASA is taking a proactive approach to fixing problems.

SciGuy liveblogged this morning's spacewalk and is the go-to site for updates on Discovery.

posted by Marsh @ 2:51 PM