WASHINGTON – A power problem on the International Space Station has delayed the launch of a SpaceX cargo spacecraft for at least two days until the problem is resolved.
NASA announced on April 30 that it had asked SpaceX to postpone the launch of a Dragon cargo probe on a Falcon 9 rocket scheduled for May 1. The launch is now scheduled for May 3 at 3:11 am Eastern.
The announcement took place one day after a part of the station power system defect. NASA reported that one of the four main switching units had ceased operation on April 29 and restoration work was unsuccessful.
The units draw power from the station's solar arrays and route them into eight channels that pass through the station. The failed unit means that two of these eight channels have no power supply. "It loses nearly a quarter of the energy to the space station," said NASA's Associate Administrator for Human Exploration and Operations, Bill Gerstenmaier, during a presentation on April 30 at a joint session of the Space Studies Board and the Aeronautics and Space Engineering Board.
This failure did not affect the operation of the station, he said, but for some key systems, including the Canadarm 2 robotic arm, which holds and moored the spacecraft Dragon as it arrives, this means redundancy loss. "We do not want SpaceX to be stationed and then have to grab the SpaceX arm and then have a power outage," he said.
The delay in starting the charge gives the controllers the opportunity to restore the station's power supply system Replacing the failed switching unit. Gerstenmaier said the controllers would replace the defective robot with the robotic arm on May 2nd. If the start is successful, it can continue on the 3rd of May and arrive two days later. A weather forecast released on April 30 calls for a 60 percent chance of acceptable weather for a launch on May 3.
This is not the first time that such a bus switching unit malfunctions, with the unit repaired in orbit in one case. "These are just lifelong issues," he said, adding that a number of spare parts were available. "It has become normal for us to take these mistakes into our hands, figure out how to intercept manifestos and just keep going."
The spacecraft Dragon carries about 2,500 kilograms of research payloads, supplies, and other equipment for the station. The scientific payloads range from biomedical "tissue chip" experiments to the Orbiting Carbon Observatory 3 experiment, which will be mounted on the outside of the station.
Gerstenmaier emphasized in his statement at the board meeting that the power supply problems would not have influenced station activity. During a broadcast on April 29, when the station's astronauts spoke to students, he said he was the only one who noticed that some lights in the Kibo module, where the astronauts were conducting the broadcast, were turned off because of the power problem. [1