A Russian unmanned cargo-carrying Progress spacecraft successfully docked with the international space station (ISS) April 26, despite a glitch in the capsule’s navigation system.

After its April 24 launch from the Baikonur Cosmodrome in Kazakhstan, the Progress 51 spacecraft failed to deploy one of the two antennas used for the Kurs automated docking system. Russian ground controllers were able to reposition the antenna, allowing the automated docking to go ahead as planned.

Russian cosmonauts Pavel Vinogradov and Roman Romanenko kept an eye on Progress as it moved into position.

Although the cosmonauts were prepared to take over docking procedures, the automated system worked and the spacecraft fully docked to the station at 8:34 a.m. EDT while flying 404 kilometers over the border between China and Kazakhstan.

The approach to the space station was slower than usual because controllers on the ground and astronauts on the ISS were carefully monitoring Progress’ position, NASA officials said.

At first the Progress was “soft-docked” and not secured in place with hooks in latches, giving the station crew and flight controllers a chance to make sure its stuck antenna posed no risk to the station’s exterior. When they saw it was safe, the Progress was slowly drawn into the port and secured.

Progress delivered 800 kilograms of propellant, 26 kilograms of air, 21 kilograms of oxygen, 420 kilograms of water and 1,519 kilograms of experiment hardware, spare parts and other supplies to the residents of the space station, NASA officials said.

Vinogradov and Romanenko are flight engineers on the station’s Expedition 25 crew, along with NASA astronauts Tom Marshburn and Chris Cassidy, and Russian cosmonaut Alexander Misurkin. The crew is led by commander Chris Hadfield of the Canadian Space Agency.