Jim Cast
Headquarters, Washington, D.C.                                                
January 7, 1993
(Phone:  202/453-8536) 

Kyle Herring
Johnson Space Center, Houston
(Phone:  713/483-5111)

Anne McCauley/Evelyn Smith
McDonnell Douglas Aerospace, Huntington Beach, Calif.
(Phone:  714/896-1300)

Release:  93-7

SPACE STATION FREEDOM PROPULSION FIRING TESTS UNDERWAY

   Static firing tests of a propulsion development test article 
for Space Station Freedom began in late December at NASA's White 
Sands Test Facility (WSTF) in New Mexico.

   The test series will validate the concept and preliminary 
design of the propulsion module to be used for space station 
attitude control, orientation, speed and altitude control and 
avoidance of space debris.  

   "Freedom is no longer a 'paper-station'," commented Richard 
Kohrs, Director of the Space Station Freedom Program in 
Washington, D.C..  "And the beginning of critical tests with the 
propulsion module system at White Sands represents the next and 
certainly not the last in a long string of reality checks for 
Freedom focussing on launch of the first element in the assembly 
sequence in about 3 years."

   "We have seen Space Station Freedom progress from concept to 
design and now to validation of hardware," said Larry Morata, Vice 
President and General Manager of McDonnell Douglas Aerospace (MDA) 
Space Station Division.  "We are on the way to constructing a 
facility that will promote science and exploration for years to 
come."

   During Shuttle's second space station assembly flight, two 
propulsion modules will be positioned on Freedom.  Two more will 
be added following man-tended capability and an additional pair 
will be added prior to permanently manned capability.
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   Early propulsion modules will have 13 thrusters located at both 
ends and on top of each module.  On later modules, the number of 
thrusters will be scaled down to nine.  The thrusters can be fired 
independently, allowing precise positioning of the station.

   The article being tested in New Mexico has 10 small thrusters, 
each with an operational range of 9 to 25 pounds of thrust and 
three large thrusters with 20 to 55 pounds of thrust.

   MDA Space Station Division, under contract to the NASA Johnson 
Space Center (JSC), Houston, is responsible for the development 
and testing.  McDonnell Douglas previously carried out structural 
dynamics and vibration testing at JSC.  The test series will 
continue at WSTF as needed to complete validation of the design.
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