HOUSTON — Russian plans to follow the anticipated July 27 arrival of Japan’s unpiloted HTV-3 resupply craft at the International Space Station (ISS) with a second attempt to re-dock the Progress 47 received ISS mission management team approval on July 26.

If the test is successful, the Progress 47 would re-dock with the Russian segment Pirs module on July 28 at 9 p.m. EDT. A July 23 docking attempt, using the freighter’s new KURS-NA automated rendezvous system, had to be aborted when the hardware failed an activation self-test at a distance of 100 mi. from the station. Instead, the unmanned cargo spacecraft passed safely below the six-person orbital outpost.

The Progress 47 undocked from the station’s Russian segment on July 22, following a three-month stay and the offloading of all supplies.

The second re-docking attempt will proceed if the ungraded Progress 47 rendezvous system passes a self-test at a distance of 28 mi. from the station, Dan Hartman, NASA’s space station program operations manager, told a news briefing. If the self-test fails, further work with the KURS-NA system will be suspended until a future Progress mission, Hartman says.

Eventually, Russia expects to incorporate the new system with its fewer antennas and upgraded electronics on Soyuz crew transports as well as Progress freighters.

Since July 23, Russian experts have made several attempts to run a self test on the box without a clear indication of the difficulties. 

“It appears to get hung up in that sequence somewhere,” Hartman says. “So it’s failing the self test, not getting all the way through it, but the avionics box itself appears to be healthy.”

Launched July 20, the HTV-3 is expected to rendezvous with the ISS early July 27. Station astronauts Joe Acaba, Akihiko Hoshide and Sunita Williams will be positioned in the Cupola observation deck at the controls of the Canadarm2 robotic arm ready to grapple the 16.5-ton Japanese cargo craft shortly after 8 a.m. EDT. Hoshide will guide the HTV-3 with its 4.6 metric tons of internal and external cargo to a berthing with the U.S. segment Harmony module just before 11 a.m. EDT

The mission management team will reconvene July 30 to approve Russian plans to launch the Progress 48 resupply craft Aug. 1 on a one-day, four-orbit docking profile.

If the Progress 47 manages to re-dock, it would be released from the Pirs docking port on July 30 at 5:19 p.m. EDT, freeing docking space for the new Progress.

The Progress 48 launch would follow on Aug. 1 at 3:35 p.m. EDT. After the abbreviated transit, the new Russian resupply craft would dock at 9:24 p.m. EDT.

If difficulties occur post-launch, the Progress 48 could revert to the normal 34-orbit, two-day rendezvous profile, which would see it dock on Aug. 3 at 6:14 p.m. EDT.

The Russians plan to adapt the faster station transits for Soyuz crew missions as well.