Russian supply ship successfully docks with station

Two days after an aborted rendezvous, an unmanned Russian cargo ship carrying 2.5 tons of supplies and equipment successfully docks with the International Space Station.

William Harwood
Bill Harwood has been covering the U.S. space program full-time since 1984, first as Cape Canaveral bureau chief for United Press International and now as a consultant for CBS News. He has covered more than 125 shuttle missions, every interplanetary flight since Voyager 2's flyby of Neptune, and scores of commercial and military launches. Based at the Kennedy Space Center in Florida, Harwood is a devoted amateur astronomer and co-author of "Comm Check: The Final Flight of Shuttle Columbia." You can follow his frequent status updates at the CBS News Space page.
William Harwood
2 min read

KENNEDY SPACE CENTER, Fla.--An unmanned Russian supply ship successfully docked with the International Space Station Sunday, two days after an interference issue with a television transmitter in a backup docking system triggered an unexpected abort.

For the second attempt, the backup TORU system was not activated, there was no interference, and the KURS automated rendezvous system worked flawlessly, lining the Progress up for a docking at the Zvezda command module's aft port.

The view of the International Space Station from the Progress 38 cargo ship during an automated approach Sunday. It was the craft's second docking attempt after an abort Friday that was blamed on interference with an on-board television transmitter. NASA TV

After a brief period of station-keeping, the cargo ship resumed its approach, docking on time at 12:17 p.m. EDT as the two spacecraft sailed 220 miles above central Asia. A few moments later, hooks and latches retracted and pulled the Progress firmly into place.

"Congratulations on the successful Progress docking," a flight controller radioed from Moscow.

"Thank you very much," Expedition 24 commander Alexander Skvortsov replied from the station.

Launched Wednesday from the Baikonur Cosmodrome in Kazakhstan, the Progress 38 vehicle is loaded with 1,918 pounds of propellant, 110 pounds of oxygen, 220 pounds of water, and 2,667 pounds of experiment equipment, spare parts, and other supplies.

During an initial docking attempt Friday, the Progress 38 craft aborted its approach and flew past the station, rotating slowly to keep its solar arrays face on to the sun.

It was the second Progress docking problem in a row for the Russians. During an approach May 1, a problem with the automated KURS navigation system aboard an approaching cargo ship forced Expedition 23 commander Oleg Kotov to take over manual control using the TORU backup system.

Russian engineers concluded the abort Friday was triggered by interference between the KURS system and a television transmitter that is part of the backup TORU system activated around the time of the abort. The result of the interference was a "cancel dynamic operations" command that prompted the Progress flight computers to abort the automated approach.

After tests to make sure redundant KURS components were working properly, Russian managers approved plans for a second docking attempt using the KURS system alone, telling the crew not to activate the backup TORU system. There were no apparent problems.