Nasa aborts space walk
Nasa misdiagnosed cause of astronaut's spacesuit water leak

Nasa has admitted that a potentially fatal spacesuit water leak which almost drowned an astronaut during a spacewalk outside the International Space Station last July, was entirely avoidable if the agency had correctly diagnosed the cause of the leak.

Astronaut Luca Parmitano's suit had leaked on two occasions in July, but Nasa thought that the water in his helmet was caused by a ruptured drink bag, according to Chris Hansen, who led the investigation into the leak that could have cost the astronaut his life.

"Had the issue been discussed in more detail [on 9th July]... the team likely would have realised that the water experienced in (Parmitano's) helmet was 'out of family' and needed to be investigated further," Hansen said in a Nasa report.

Then, on 16 July, about 1.5 litre of water leaked into the astronaut's helmet and reached up to his eyes, drowning his nose and ears, such that he could hardly breathe or hear.

Parmitano radioed ground controllers that his helmet was being submerged in water, but Nasa could not realise that the real reason for the leak was botched up systems in the suit, even as he lost radio communication later.

When the astronaut was finally taken intothe space station after one-and-half hours of spacewalk instead of the planned six hours, his breathing was seriously affected.

"Once the water got big enough that it went all the way around and started coming outside the edge of the white plastic piece, then it saturated his communication cap, and sort of capillary flow just brought the water all around his head," Chris Cassidy, fellow astronaut on the spacewalk, explained in a Nasa video release.

Normally, water leak would have caused the fan to shut down, signalling suit failure, but that did not happen, which misled the Nasa scientists on the real problem with the suit, and let the complication to persist long enough to become lethal.

"This was a really subtle problem. It took us weeks before we started getting to the conclusion that this had happened earlier," Hansen was quoted as saying by Reuters.

Contamination Problem

It was later found that the leak was due to contamination in the spacesuit's cooling system, which is still under investigation.

Interestingly, another mishap was barely averted the next day when the astronauts were drying the spacesuit with a vacuum cleaner, accidentally draining oxygen from a tank.

"The hazardous mix of electricity and pure O2" could have sparked a fire, the 220-page Nasa report stated.

"We're taking it very seriously," Mike Suffredini, space station programme manager, told AP.

"The message to all of us is to be really vigilant, right, and to really communicate," he added.

The serious mechanical problems reminded Nasa scientists of the 1986 Challenger and 2003 Columbia accidents, which killed all 14 astronauts onboard, seven in each flight.

"I think it's a tribute to the agency that we're not hiding this stuff, that we're actually out trying to describe these things, describe where we can get better. That's how we prevent Columbias and Challengers," William Gerstenmaier, Nasa Associate Administrator for the Human Exploration and Operations told reporters.

He further emphasised that the latest incident was "an excellent reminder for us" to prevent future disasters.