Space Station Experiences Partial Cooling Shutdown

This points out the need for heavy spares missions. I wonder if Dragon would be able to lift the 750 pound pump module.

Unfortunately, once the shuttle retires they would have to build new replacements instead of refurbishing the failed units.

Can the ISS really survive without the Shuttle or a SD HLV soon?

The JAXA HTV can lift the this Pump.

STS-127 left a spare on-orbit, so they can replace it now. Hopefully, it can be removed and returned to Earth before the shuttle program ends so that it can be studied.

Things are expected to fail, so as long as things are failing at an acceptable rate...

"The JAXA HTV can lift the this Pump."

Will the pump fit inside the HTV? The large size of some of the spares has been a big problem post shuttle. The SpaceX Dragon web page says that it has 490 ft^3 of unpressurized cargo space which seems like it could carry it unless the pump's dimension's are too big to fit.

The station's spares were probably calculated to last until 2015. If the station's lifetime is extended, that probably would require some heavy spares to be built and launched before then.

That's a question that has only ever been hand-waved away, IMHO. If nothing else, this incident will make those who campaigned for STS-135 (and the outside chance of an STS-136) seem prescient.

Right now we can likely get this returned on one of the last 2 or 3 Shuttles and maybe send it back up on HTV or another vehicle once its been fixed. The failure came in the nick of time. In another year we would be SOL and if its one of the last 2 pumps that fails, we start shutting down a significant part of ISS-for the long term. Real shortsightedness on the part of our illustrious management.

We have two reasons for wanting to bring that pump back on the shuttle. Of course we would like to refurbish it and return it to space. But more importantly we need it for forensic work so we know what service life to expect from the other five pumps on orbit, and maybe learn some tricks to extend that life. I wish Mike Suffredini had been more optimistic. Perhaps the hardware needed to transport this pump is incompatible with the AMS and Leonardo payloads. I thought he implied it would take an act of Congress (a prompt shuttle budget extension) just to bring it home. That's you, Congress!

I read one report (CBS News?) that they don't have room on the current shuttle missions to bring it back, but if the extra flight is added they could.

If memory serves me, the last shuttle spares flight was eliminated and the flight used for the AMS. If they add the extra flight, they would have the previously planned spares flight.

Logistics requirements for extending ISS to 2020 and beyond haven't been hand waved away. 2 or 3 years ago the logistics folks in the ISS program office reviewd the ISS sparing plan in regard to flying ISS to those later years (we knew it was going to be extended and did the work up front to know it was executable without the shuttle). Any additional spares requirements were identified then and contracted for. The MTBFs used in the calculations are extremely conservative (it's about 4 times better then predicted in the system I work on)so we got plenty of margin. Bottom line is that this kind of failure is expected (that's why there are four spares on orbit)and the crew is trained for (one of 14 generic EVA tasks all ISS crews are trained to do). Important that the R&R be done quickly to regain redundancy because if you loose the other loop then things get ugly but not a dire emergency. This does nothing to change the plan to retire Shuttle.

Did the sparing plan include the loss of the shuttle to return failed equipment requiring new replacements to be built, or were they planning on having all large spares on ISS to support it through 2020?

Here's my Q: What is the cost of new ORUs as compared with the cost of refurbishment?