Russian cargo ship completes express flight to International Space Station
A Russian Progress cargo ship carrying 3.7 tons of supplies and equipment blasted off from Kazakhstan Thursday and executed a flawless two-orbit dash to the International Space Station, the second test of a fast-track rendezvous procedure that may eventually be used for piloted Soyuz flights.
The Soyuz 2.1a rocket carrying the Progress MS-11/72P spacecraft roared to life at 7:01 a.m. EDT (GMT-4; 5:01 p.m. local time) and quickly thundered away from the Baikonur Cosmodrome to kick off the abbreviated three-hour rendezvous.
At the moment of liftoff, the space station was 316 miles from the cosmodrome, approaching the base on a southwest-to-northeast trajectory. The Progress launching was precisely timed to allow the cargo ship to climb directly into the plane of the station's orbit, a requirement for all rendezvous missions.
The space station, moving at some 17,000 mph, passed directly over Baikonur about 38 seconds after the Progress took off and quickly moved ahead of its pursuer. At the end of the cargo ship's eight-minute 45-second climb to space, the station was 1,049 miles in front of the Progress.
Starting about a half hour after launch, the supply ship carried out a series of rendezvous rocket firings to catch up with its quarry after just two trips around the planet, smoothly moving in for a gentle docking at the Russian Pirs module at 10:22 a.m. as the two spacecraft were passing above central China.
On board: 3,375 pounds of propellant for use adjusting the station's altitude; 104 pounds of oxygen and air; 926 pounds of water; and 3,117 pounds of dry cargo.
Reaching the station in just two orbits requires precise timing and a complex mix of launch-day specific conditions for both the launcher and the lab complex. Thursday's flight was just the second to get off within those constraints.
Up until 2012, Soyuz ferry ships and Progress cargo craft took two days, or 34 orbits, to reach the station. Then, keeping the two-day profile available as a backup, the Russians implemented a four-orbit rendezvous, shortening the time crews had to spend cooped up in the cramped Soyuz to just six hours or so.
The new technique would shave another two hours off that, but it's not yet known when the Russians might attempt the speedier rendezvous with a Soyuz crew.
The Progress MS-11/72P launch was the first of three planned space station supply runs in April.
A Northrop Grumman Cygnus cargo ship is scheduled for launch from the Mid-Atlantic Regional Spaceport - MARS - on Virginia's east coast on April 19, following by a SpaceX Dragon flight from Cape Canaveral on April 25. The next two resupply flights after that, one by a SpaceX Dragon and the other by a Progress, are planned for July.
