On December 16, 2006, an undiscovered 2-centimeter (0.75 inch) cut was accidentally made into the protective outer layer of the inside portion of the right glove of astronaut Robert Curbeam. The problem occurred during STS-116, the mission of the Space Shuttle Discovery that occurred from launch on December 9 to landing on December 22, and which involved an assembly mission to the Space Station.

It is likely, according to investigations performed by NASA, the incident occurred when Curbeam and Sunita Williams transferred external station shielding from the Space Shuttle to the International Space Shuttle. The cut was not found until NASA ground personnel inspected the spacesuits in February 2007.

NASA officials are surmissing that the cause of the cut was from a metal burr from a metal rod in the payload bay of the Shuttle Discovery. However, they have not excluded other possibilities.

The gloves worn by the U.S. astronauts during EVAs consist of five protective layers: the outer layer (about the thickness of shirt cloth) is a laminated layer that covers part of the glove and helps to add gripping strength to the bulky gloves; the next layer is a strong “Vectran” fiber that protects against cuts and abrasions; the third layer is a nylon layer, the fourth layer is a rubber bladder, and the innermost layer is used to keep the bladder layer off of the skin of the wearer.

The cut penetrated into the second outermost layer, the Vectran layer, so was of no immediately safety concern to Curbeam.

Vectran, similar to Kevlar that is used for bulletproof vests, is a synthetically manufactured aromatic polyester fiber that is made from liquid crystal polymers. Celanese Acetate LLC created Vectran and Kuraray Company, Ltd. manufacturers it. Besides its use with NASA spacesuits, Vectran was also used on the airbags used for the landing of the Mars Pathfinder and the twin Mars Exploration Rovers (Spirit and Opportunity). Vectran is commonly used as reinforcing fibers on ropes, cables, and advanced composite materials.

Because of the incident, NASA is changing its mission procedures so that the astronauts perform periodic and rigorous inspections of the gloves. After every major assembly task outside of the Space Station (which occurs about once per hour), the astronauts will inspect their gloves. If anything unusual is found, they will end the spacewalk.

Besides mission specialist Curbeam, the STS-116 crew also included commander Mark Polansky, pilot William Oefelein, and mission specialists Nicholas Patrick, Christer Fuglesang, and Joan Higginbotham. The mission also brought Space Station flight engineer Sunita Williams onboard and returned flight engineer Thomas Reiter to the Earth.

The STS-18 crew aboard Space Shuttle Atlantis will be using the gloves on their upcoming mission that is scheduled to liftoff on June 8, 2007 for another assembly mission to the International Space Station. They have already been briefed and trained on the new glove inspection procedure.

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