Preventing Another Space Shuttle Disaster

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The space shuttle's thermal protection system is a combination of Reinforced Carbon-Carbon (RCC) on the wing leading edge, thermal blankets on the fuselage and thermal protective tiles covering the underside of the vehicle and nose cap. This system protects the spacecraft and its human occupants from the extreme heat of reentry into the Earth's atmosphere. Without the RCC, blankets, and tiles covering the shuttle--the space shuttle Endeavour has more than 24,000 tiles--the structural integrity of the aluminum frame on the shuttle would be compromised. In 2003, the world witnessed a devastating disaster after the RCC on the port (left) wing of the space shuttle Columbia was damaged during launch. The damage went undetected and the shuttle, left with a compromised heat-resistant shield, lost structural integrity and broke apart during reentry.

NASA engineers used six 3-D scanners for their prelaunch inspections of Endeavour and plan to use them again when the shuttle returns. They will also use them for the ground maintenance of other spacecraft. The next step for the new scanner, says Lavelle, is to redesign it so that its components can withstand operations in space, and astronauts can use it to inspect the space shuttle during missions. Lavelle also says that there are many companies, which he declines to identify, interested in the 3-D scanner.

Aside from inspecting the space shuttle, the scanner is being used to evaluate thermal protection materials for a new crew exploration vehicle that NASA is developing. Engineers use the 3-D scanner to measure the materials both before and after they are tested in extreme environments; the difference between the two measurements indicates how well the material performed. Planetary rovers could also use the scanner to map the space around them in 3-D, helping them avoid collisions and better maneuver in unknown environments.