Progress Docking Completed
Progress 51 Cargo Craft Docks to Space Station
“The ISS Progress 51 cargo craft completed a two-day journey to the International Space Station when it was captured at the Zvezda service module on Friday at 8:25 a.m. EDT, the cargo craft completed a hard mate when the docking hooks were deployed at 8:34 a.m.”
Umanned Russian spaceship suffers mishap on way to ISS, AFP
“An unmanned Progress spaceship racing to the International Space Station with 2.5 tonnes of cargo on board failed Wednesday to deploy a key antenna that helps it dock with the orbiting lab in the latest hitch in Russia’s space programme.”
Wow, the tone of that news report is completely different than any other’s I’ve read about this. This is a minor glitch. Something to be carefully watched, of course, but a minor glitch. There is a reason these systems have ample redundancy, after all, and the mission can proceed as normal.
Nothing like the past (and serious) quality control issues that have been plaguing the Russian industry, so I don’t get why the parallels are drawn. None of those affected the Soyuz or Progress production lines, which have a launch history any US company would be proud (and envious) of. I guess politics apply, so good thing I know how to read between lines… but others won’t.
See? No sweat, hard docking completed. Good for them! 🙂
I do agree the “The incident threatens to cast a new shadow over a once-vaunted programme that competed with the United States for space supremacy” in the article was ridiculous.
I wonder if all else fails if they could use the canada-arm to capture it and dock that way
I’m not sure if Progress or Soyuz have an appropriate grapple fixture for that arm.
Have they successfully docked with the ISS without this antenna in the past? Anyone know?
JH:
The antenna that didn’t deploy was for the long range system (Kurs) that helped get Progress to within a couple hundred yards of the station. Don’t know how they got that close but they did. Then the close range system (Tors) took over for the rest of the docking procedure. They did fine. No surprise with forty years of experience under their belts. Quality control might be an issue but the Russian’s don’t lack talent!
tinker
My guess is that the loss of one antenna only slightly reduced the accuracy of the Kurs system, but still within tolerance. Don’t know if you are referring to the manual TORU backup system which allows a station crew to manually dock Progress by remotely controlling the thrusters, using video that is provided by Progress. I don’t think it was used today. Although as always the TORU system would have been activated and the crew ready to take over if needed, but as far as I know they didn’t need to.
Although it may turn out to be a non-event, the stuck antenna could prevent a hard docking, although a soft docking could be achieved. NASA mission rules would probably not allow the docking to proceed, but the Russians are more prone to take such risks. Could get interesting … my predictions: the antenna will remain stuck, hard dock will still be achieved but the antenna will be a potential problem for undocking. The Progress will be examined during the next scheduled Russian spacewalk and deemed safe. Then much later the first attempt at undocking will be unsucessful. But while a spacewalk to troubleshoot is being worked, repeated attempts to undock are eventually successful. Future Progress and especially Soyuz missions will not be allowed to use this docking port until the port is inspected and repaired. Or not! 🙂
A soft-docking is where the two spacecraft are in contact but not sealed together. A hard-docking is where the two spacecraft are pressed together to create an airtight and mostly-stationary link between the two. Hard docking is a prerequisite for opening the hatch.
The Russians have been at this a long time. Like the old days at NASA, they get the job done instead of sitting on their hands and pointing fingers at others.
It seemed strange to me that they weren’t sure if the antenna would hit or not. “Listen for grinding noises” isn’t the best solution but maybe they knew it would be ok even if it hit a bit…?