"The adjustment of the ISS's orbit is scheduled for February 16. It is planned that the engines will impart one impulse to the station at 16:20 Moscow time, which will lift its altitude by approximately three and a half kilometers," he remarked.
The last time the ISS's altitude was lifted was on January 15. At that time, the station, which is approaching the Earth daily by 100-150 meters, was given a one-time "lift" of 8.5 kilometers.
Part of the reason was to overcome the altitude shortfall made on November 17, 2004, when the ISS fell 2.7 kilometers short of its target altitude because of an inadequate pattern of fuel feeding to the engines.
Vladimir Solovyov, responsible for control of the Russian segment of the ISS, summing up the results of work done by a technical commission, said earlier: "We checked everything and found that our ground-based mathematical rigs, which always make preliminary computations, cannot take all into account."
According to Solovyov, "because of that we used a different pattern of fuel feeding with lower pressure, and, although the engines worked the allotted time, their thrust was about 40% of the calculated value."
The flight director of the ISS's Russian segment gave an assurance that the modeling rigs would be upgraded. "The rig program will be updated, with new mathematical models added to it," Solovyov said.
The current orbit adjustment is a scheduled operation. It will be carried out to prepare the station for a docking with the next Progress cargo ship.
