For Release: June 13, 1996

Steve Roy
Office of Media Services
(205) 544-0034
steve.roy@msfc.nasa.gov

RELEASE: 96-49

INTERNATIONAL SPACE STATION’S TRUSS/POWER SYSTEMS TESTED AT MARSHALL CENTER’S NEUTRAL BUOYANCY SIMULATOR

A major segment of the backbone of the International Space Station completed testing in the simulated weightlessness of a special water tank at NASA’s Marshall Space Flight Center in Huntsville, Ala.

The Space Station’s centrally located Z-1 truss structure, which houses the communications and tracking, attitude stabilization, thermal control, and electrical power distribution systems, was the focus of a three week test in the Neutral Buoyancy Simulator.

Assisted by test and safety divers, astronauts teams simulated procedures which will deploy antennas, provide cooling to laboratory equipment, and bring electrical power to the Space Station. Also, the test evaluated the use of mobility aids, handling of equipment, use of foot restraints and hand holds for spacewalks during Space Station truss assembly.

"The test and development of procedures for truss assembly and maintenance mark an important milestone for the Space Station program," said Randy Brinkley, International Space Station Program Manager at the Johnson Space Center in Houston, Texas. "The highly successful work accomplished in the neutral buoyancy simulator is a major milestone in the schedule for the launch of these critical elements of the Space Station."

"Neutral buoyancy provides an excellent environment for testing hardware designed to operate in space while affording the opportunity to evaluate procedures that will be used in space to assemble structures such as the Space Station," according to Bill Barnett, test director at the Neutral Buoyancy Simulator.

"By attaching a system of floats and weights suited subjects or equipment neither sink nor float, making the subjects and equipment neutrally buoyant,"said Barnett. "The neutral buoyancy facility provides a realistic simulation of working in space, permitting astronauts to test equipment designs, use of tools and to work through portions of actual mission timelines for assembly of objects in space."

"We tested the design for assembly and maintenance of the Space Station’s electrical power system and the interfaces to the power system," said Ron Lovely, Rocketdyne Manager of Space Operations and Flight Experiments. "Also, we evaluated tasks and equipment which provide power and other necessary functions to make the living and working places on the Station habitable."

The simulations at Marshall Center, Lovely said, "are how we find out if we are meeting all the requirements for extravehicular activities or spacewalks. This series of tests have gone extremely well. We are very excited and pleased about the progress made toward the verification of the Station for assembly and maintenance in space."

The test was conducted by Rocketdyne with support from the Marshall Center and the Johnson Space Center Mission Operations Directorate. Rocketdyne, based in Canoga Park, Calif., is responsible for development and delivery of the electrical power system and associated truss structures for the Space Station.

The first Space Station element, a Russian built, U.S. funded control module called the FGB, will be launched in November 1997.

In December 1997 the U.S. Node, which serves as an attached point to other U.S. and international partner modules, will be launched by the Shuttle and attached to the FGB.