An investigation into the dangerous leak of water into a spacesuit during a spacesuit last July has found that NASA engineers had missed an earlier failure of the same suit.

An investigation into the dangerous leak of water into a spacesuit during a spacesuit last July has found that NASA engineers had missed an earlier failure of the same suit.

The leak had first happened in a spacewalk a week earlier, and engineers misdiagnosed the problem. In addition, it appears they didn’t look closely enough at it.

Meanwhile, the investigation has pinpointed the cause of the leak as a clogged filter, but still could not trace what caused that clog.

A detailed update on the status of spacesuit repairs on ISS, following the July water leak during a spacewalk.

A detailed update on the status of spacesuit repairs on ISS, following the July water leak during a spacewalk.

After additional tools and parts were sent up on both Progress and Cygnus freighters, astronauts on ISS pinpointed the problem and replaced the failed the “fan/pump/separator”. The faulty unit was brought back to Earth for further analysis in the manned Soyuz craft yesterday.

Of the four U.S. spacesuits on ISS, one is still considered faulty and needs to be replaced, which will happen with the next Dragon flight expected sometime in February 2014.

The investigation into the spacesuit leak in July is now awaiting the return of equipment from ISS.

The investigation into the spacesuit leak in July is now awaiting the return of equipment from ISS.

The station astronauts removed a cooling system pump and small contaminants found in the garment’s Primary Life Support System plumbing. The old fan pump separator and the preserved contaminants, including a 1-cm. piece of plastic, will return to Earth aboard Russia’s TMA-09M crew transport late Nov. 10 with Parmitano, NASA astronaut Karen Nyberg and ISS Russian commander Fyodor Yurchikhin. The hardware and contaminants will then be flown by NASA transport from the Kazakh landing site to Johnson Space Center, where a Mishap Investigation Board (MIB) hopes to quickly complete its probe of the worrisome incident.

Though it appears they have narrowed the problem to a small number of components, the need to return these components to Earth illustrates an overall design flaw with the space spacesuit. When the shuttle was flying regularly these components were easy to return to Earth, which is why NASA designed its suit for maintenance on the ground. Now that the shuttle is gone, however, it is difficult to get components returned, which makes spacesuit maintenance difficult if not impossible.

Spacesuits need to be repairable in space. If you are orbiting Mars and one fails, you can’t call in a repairman from Earth to fix it.

Despite the astronauts’ success on ISS in recreating the spacesuit water leak, NASA engineers still do not know its cause.

Despite the astronauts’ success on ISS in recreating the spacesuit water leak, NASA engineers still do not know its cause.

What is unstated about this problem is that, because we used to have a big space shuttle with lots of cargo capacity, the American spacesuit was designed to be maintained and repaired on the ground. In the past the next space shuttle flight would have brought a new spacesuit to the station while taking this defective suit back to Earth for analysis and repair. Now that we don’t have a big space shuttle, our complex spacesuits are far more difficult to troubleshoot.

The solution? First, keep it simple. The Russians, limited by the capacity of their Progress and Soyuz capsules, made their Orlan spacesuit very simple and easy to use.

Second, get as many redundant replacements of the shuttle operating as soon as possible.

Astronauts on ISS have successfully recreated the water leak in the defective spacesuit that almost drowned an astronaut last month.

Astronauts on ISS have successfully recreated the water leak in the defective spacesuit that almost drowned an astronaut last month.

They now have a very good idea of the components that caused the failure, and will be able to replace these with new parts. The next step will be to test the suit under the same conditions with the new parts.