Skylab Astronauts Don Space Suits Again To Help New Generation Of Engineers Ready Space Station

HUNTSVILLE, Ala., Sept. 5, 1995 -- It was in 1974 that Apollo astronauts Jerry Carr and Bill Pogue set a long- standing U.S. space endurance record by spending 84 days in orbit aboard Skylab -- America's first space station. Twenty- one years later, Carr and Pogue are still in the saddle, donning space suits again to help Boeing Defense & Space Group engineers complete a series of underwater tests important to the development of the International Space Station.

The tests, conducted by Carr, Pogue, former shuttle astronaut Bob Springer and other Boeing engineers wearing space suits, were carried out of NASA's Neutral Buoyancy Simulator (NBS) at the Marshall Space Flight Center in Huntsville, Ala. The tank, holding 1.3 million gallons of water, is used to simulate the near-weightless environment of space.

Testing For The Space Station

Engineers carried out the tests to gain an understanding of the necessary restraints and mobility aids needed to stabilize the crew and equipment. They investigated the replacement of the Carbon Dioxide Removal Apparatus, a critical piece of life-support equipment.

The engineers also experimented with a system to isolate the science payloads from random vibrations that can occur in space vehicles. This active rack isolation system (ARIS) is installed on-orbit to enhance the conditions of microgravity for space sciences.

The evaluation team rehearsed the procedures needed to hook up the exterior power and data cables as the International Space Station evolves from a single element into a community of international elements. The team wanted to gain first- hand knowledge about how the equipment will work in orbit when it becomes part of the Space Station.

The Boeing team simulated astronauts working with the equipment outside the space station (extra-vehicular activity or EVA) and inside the station (intra-vehicular activity or IVA) during the neutral buoyancy tests. Full- scale mockups of the Space Station modules were placed inside the tank to create a realistic simulation of the Space Station in orbit.

From Skylab To Space Station

"These development tests ensure the basic hardware designs are compatible with EVA and IVA operations," said John Winch, Boeing vice president and Lab/Hab manager. "If we need to modify our designs in some way to make the equipment more user-friendly, we'd like to find out now and not wait for astronauts to discover a shortcoming 220 miles above Earth when the Space Station is on-orbit."

The tests evaluated many Space Station tasks including equipment assembly, use of mobility aids and restraints, the handling of experiment and equipment racks, and a thermal control system heat exchanger.

Twenty-six Boeing engineers took part in the tests over a six-week period, including the two former Skylab astronauts and a space shuttle astronaut.

Carr and Pogue, along with Springer, a former mission specialist who flew on two shuttle missions, all found themselves back in the "weightlessness" of space during the neutral buoyancy tests. All three former astronauts now work for Boeing on the Space Station program.

"Working underwater is very close to what it's like working in the zero-g environment of space," Carr said. "It's a very good training aid.

"We're trying to take a lot of the lessons we learned on Skylab and put them to use in the design of the Space Station," Carr said. "We are evaluating equipment while it is still in development to make sure it behaves like we think it will in space."

Terri Hall, a Boeing human factors specialist, is one of two female engineers who also donned an astronaut suit for the underwater tests.

"We're paying particular attention to how well things function for astronauts wearing space suits, where both visibility and dexterity are limited by the bulk of the suit," Hall said.

Not only designs, but procedures for building the Space Station also were refined during the tests.

"We learned almost as much procedurally as we did design- wise," Carr said.

A crew of six current NASA space shuttle astronauts also evaluated the equipment in the water tank. The test results now are being reviewed and analyzed for a final report.

The first piece of the International Space Station is scheduled for launch in November 1997. Boeing Defense & Space Group is NASA's prime contractor for the Space Station and is building the U.S. laboratory module, habitat or living quarters module and two connecting node modules that serve as passageways to the Space Station's other modules.