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0 pointsBitsAndObjects2mo ago0 comments

So why do they need to use helicopters and a risky airlift to return the astronauts to the main vessel? Why not just use the speedboats to take them back? Seems really odd and I can’t find any reasonable explanation.

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4 comments · 2 top-level

stackghost2mo ago· 2 in thread

>Why not just use the speedboats to take them back?

They actually covered this in the broadcast: Helicopters are faster to get the astronauts to medical, smoother in rough seas, and there's less risk of being swamped by a rogue wave. Plus, since the astronauts might have fatigue/muscle atrophy/whatever, it complicates potential boat transfers.

Brybry2mo ago

The public information sheet implies that in poor weather/rough seas they would do crew recovery in the well deck, sort of like how Dragon works. [1]

From the broadcast, they made it sound like a big factor is the 2 hour program requirement to get the crew out of the capsule. Maybe they can't reliably hit that mark with a well deck recovery?

[1] https://www3.nasa.gov/sites/default/files/files/orion-recove...

tedd4u2mo ago

The other reason is that the capsule can splashdown far away from the ship. In this case it was close (3km or so). It can possibly fall much farther away. In which case boats would be much slower. Add in the possibility of rough seas & bad weather the helos make sense. And just to keep things simple I think they just use them no matter what. Prevent errors. Also gives a chance to rehearse and debug the full recovery process in case it’s actually really needed the next time.

_moof2mo ago

Helicopter -> large boat is much easier, and much faster, than small boat -> large boat. And it's not riskier. I know the inherent risk in flight is greater, but it's also much more managed, so the actual risk is less.

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