Tuesday, August 02, 2005
Cartoon #201: Shuttle Repairs
The Space Shuttle Discovery was found to have a couple of loose pieces of fabric dangling from tiles near its forward landing gear. Despite initial problems during launch on July 26, 2005, NASA said that preliminary investigations showed that Discovery was safe to fly home. Several days later, the loose pieces of fabric were determined to be a big enough danger to require a spacewalk to pull them off the orbiter.
During the launch, images from new cameras revealed that a section of foam weighing some 250 grams fell away from the external fuel tank, but did not strike the orbiter. However, NASA announced the grounding of all further planned Shuttle launches until they have a firm understanding of why the foam came off, and how to correct it.
A piece of foam striking the Columbias wing during lift-off in January 2003 was responsible for the loss of the craft as it made its reentry to Earth's atmosphere.
A team of 200 experts studied all video and still footage taken of the shuttle during launch, and on approach to the International Space Station (ISS). In a first, before Discovery docked, the Shuttle performed a slow back-flip some 180 meters from the ISS enabling the two-man crew of the space station to take high-resolution images of the underside of the orbiter.
As part of the check for damage the crew of Discovery used a laser-scanner on the robotic arm to inspect the crafts wing leading-edges and nosecone. Images of the belly of the Orbiter were checked later in the week. Near the forward landing gear, loose fabric was spotted and determined to be a potential danger during reentry.
On Monday, August 1, mission managers gave the go-ahead for astronauts to remove the two protruding gap fillers in Discoverys heat shield during a Wednesday space walk. Plan A called for Soichi Noguchi and Steve Robinson to attempt to simply pull the thin fabric fillers from between tiles in the forward area of the orbiters underside. If the pull method is unsuccessful, Plan B called for the use of tools to cut the material flush with the surface.
Spacewalk experts presented the plans to mission managers in Mondays Mission Management Team meeting. Space Shuttle Deputy Program Manager Wayne Hale, in a Monday afternoon briefing, said that the level of uncertainty involved in flying a reentry with protruding gap fillers made it an easy decision to proceed with a well-understood process for removing them.
Another way of saying well-understood is: Its not rocket
science. But this is rocket science. This cartoon translates this particular rocket science into a classic clown shtick. Anytime a clown pulls a loose thread from another clown, expect major unravelling to ensue.