Russian Analysis of Failed ISS Reboost Nears Completion

Russian Analysis of Failed ISS Reboost Nears Completion
Engineers work to integrate the Progress 19 supply ship into its Soyuz launch vehicle in preparations for its Sept. 8, 2005 launch toward the International Space Station (ISS).
(Image: © RSC Energia.)

KOROLYOV,Moscow Region (Interfax) - The Mission Control Center in Korolyov near Moscowhas almost completed its analysis of the sudden halt in the firing of theProgress M-54's engines during correction of the International Space Station's orbit,Energia corporation Vice President and Russian commander of the ISS flightVladimir Solovyov told Interfax on Monday.

"Ourexperts have generally understood the reasons for the situation. We think itwas an unstable indicator in one of the eight Progress engines," he said.

It wasplanned to correct the ISS's orbit with the help of Progress's engines onOctober 19. The engines were due to fire for 700 seconds, but theyautomatically shutdown 77 seconds after they were switched on. The ISS's orbit was raised by100-150 meters, instead of the planned 10 kilometers.

A testcorrection of the station's orbit is scheduled for October 26 to confirm theexperts' theory, Solovyov said. "We will briefly turn on the engines forraising the ISS by approximately one meter per second and see how itgoes," he said.

If theexperts' theory is right, another orbit correction will be considered, he said."We can do that on November 9, 16 or later," he added.

The ISSorbit will have to be raised for the December docking with the Progressfreighter, which will be launched from Baikonur on December 21.

The ISS isorbiting at a safe altitude, Solovyov said. "The Sun is passing through aperiod of minor activity, and the orbit daily drops by approximately 50 meters.The current height of orbit is about 350 kilometers, so the orbit will remainsafe without correction for 1.5 years," he said.

Russia doesnot want to lift the ISS orbit to 390-400 kilometers, which would require nofurther corrections, Solovyov said. "The thing is that 340-350 kilometersis best for docking with U.S. Space Shuttles. We are thus meeting the interestsof our American partners," he said.

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