It was a throwback of sorts Wednesday as a Russian Progress cargo craft launched on a two-day track in pursuit of the International Space Station, reverting to the old rendezvous style instead of the six-hour sprints employed recently, but one of its navigation antennas did not immediately deploy.

Loaded with 3.1 tons of food, fuel and supplies, the freighter was boosted into orbit atop an unmanned Russian Soyuz booster from the Baikonur Cosmodrome at 6:12 a.m. EDT (1012 GMT). The space station was located over the South Atlantic at the moment of launch.

Main engine ignition. Credit: NASA TV

The preliminary orbit was achieved after a nine-minute ascent provided by the three-stage rocket, and onboard commands were issued to unfurl the craft's communications and navigation antennas and extend two power-generating solar arrays that span 35 feet.

However, initial telemetry indicated one of the antennas for the KURS automated rendezvous system -- the hemispherical antenna on the side of the spacecraft -- did not immediately deploy as expected. Russian flight controllers are assessing the situation and any potential impacts.

The antenna in question is used for sending and retrieving navigation signals, according to Brandi Dean, NASA's mission control commentator in Houston, and is one of five in the KURS package aboard the Progress.

A series of precise engine firings is scheduled over the next two days to guide the Progress toward a planned autopilot rendezvous with the station for docking Friday at 8:26 a.m. EDT (1226 GMT).

Unlike the last three Progress cargo craft, this resupply ship was forced to take the typical two-day rendezvous because of the phasing and orbital mechanics associated with launching today. Only certain days provide the proper conditions for the six-hour rendezvous profile.

The 24-foot long ship will attach itself to the aft port of the Zvezda service module, which became available last week when a previous Progress flew away to fly solo for daily thruster firings to help ground controllers in Russia calibrate radar systems before its eventual deorbiting into the South Pacific on Sunday.

Today's launch was known in the station's assembly matrix as Progress mission 51P. The spacecraft's formal Russian designation is Progress M-19M.

The craft will bring nearly three tons of supplies to the station. The "dry" cargo tucked aboard the Progress amounts to 3,483 pounds in the form of food, spare parts, life support gear and experiment hardware.

The refueling module carries 1,764 pounds of propellant for transfer into the Russian segment of the complex to feed the station's maneuvering thrusters. The vessel also has 926 pounds of water and 48 pounds of oxygen and 57 pounds of air.

The space station is staffed by the Expedition 35 crew of commander Chris Hadfield from the Canadian Space Agency, NASA's Tom Marshburn and Chris Cassidy and Russian cosmonauts Roman Romanenko, Pavel Vinogradov and Alexander Misurkin.

The cosmonauts will be standing by Friday to take over manual control of the approaching Progress spacecraft if the autopilot experiences a problem. They spent time Thursday checking out the backup system.