Yesterday NASA gave Space X permission to dock their unmanned Dragon space capsule at the ISS. How does this compare to the docking of the ESA ATV “Jules Verne”? When ESA docked with the ISS in 2008 there were extensive testing and trial runs. Will Space X be held to that standard? Or is NASA lowering the standard to enable Space X to meet the contract? Since the only information I can find on the web is from the Space X website itself, I am hoping Stranger or someone who understands such things can comment.
I don’t know, but usually the first time you let a outsider play with your expensive toy you are more cautious then after you find that it is really no big deal and nothing to worry much about.
Except that it remains a big deal to the people on the station…
The jules verne docking, iirc, was autonomous. I think the space x docking wil be handled by the station personnel using the robot arm on the station. Still, pointing a large object at a fragile station seems inherently risky to me. There have been life threatening collisions before (on the MIR space station).
IIRC the article said the docking would happen a week after rendezvous - suggesting they would be doing some signifcant maneuvering tests, not just point the thing at the dock ring and press go. Plus, presumably they have done some various maneuver tests beforehand or in the lab. Apparently their first orbit (previous launch) they did some maneuvering tests to simulate docking.
I understand that there will be testing. I am interested in any contrast between how the ESA Jules Verne was treated vs how the Dragon capsule will be treated. I know the JV had to perform emergency abort manuvers prior to docking, and demonstrate it’s ability to operate within tight tolerances near the station. As for manuveurs on previous tests, sorry I don’t count those. The issue isn’t whether the capsule can conduct tight manuvering under perfect conditions, but whether the station produces some interference or complexity that causes problems. Anything from radio transmissions to sun glint could be a problem.
You seem to be implying that a private company would cut corners on safety. I don’t understand your logic. SpaceX stands to win a substantial contract if it can dock successfully. Any kind of mishap especially one that damaged part of the ISS would cost SpaceX hundreds of millions, or billions in lost contracts, damage to their reputation etc.
If anything I would think a private company at such a crucial stage would be more thorough in safety tests than a government agency.
It is quite common, in high tech, for private companies to have difficulty communicating with the outside. This is, in part, due to IP protection issues. Remember that the Mars Orbiter was lost due to Lockhead Martin engineers outputting English units when the program called for metric. I’ve worked on contracts with similar companies, and this is pretty typical.
Notice, Lockhead Martin is not sweating it out on government contracts, BP is happily pumping oil, and Goldman Sachs is hitting record profits. The fact is, there is much higher accountability in government then there is in private industry.
That might be true in general but I still maintain that in this specific case, any damage to the ISS would be such a disaster for SpaceX’s future that they are likely to have taken extreme measures to prevent this.
The rules are being set by NASA. I am not implying that Space X will cut corners…
NASA was the one that approved the docking. I am just wondering whether NASA, now that they have no US means of getting to the ISS, aren’t being as careful as they used to. As a contrast to my concerns, note that while the Jules Verne went through several tests, the JAXA supply ship docked on it’s first mission. So these decisions are being done on a case by case basis.
I’m only going by what I can see at a quick glance on Wikipedia, but it seems that the difference between the ATV and other vehicles is that it is intended to dock to the ISS using a fully-automated system, whereas the others are manually docked to the station by the astronauts, using the Canadarm. It would make sense that a new craft using a new procedure would require more testing than a new craft using a familiar procedure.
(Bumped because the Dragon capsule launched today.)
Here is a Pop Mechanics article about it. The Dragon will definitely be carefully tested as it approaches the “hallowed Keep Out Sphere, an imaginary circle drawn 566 feet around the station.”
Read more:SpaceX Launches to the ISS. Now What?