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by daveoflynn 2507 days ago
> after some inflection point, does your likelihood of survival actually increase with altitude?

For humans, no. After ~10sec you’re falling at terminal velocity, which is generally 2-300km/h, and your odds of survival are extraordinarily close to zero.

This lady had a double malfunction, where there were issues with both main and reserve parachutes, but per a police report (1), she was descending at 60km/h, so she must have had at least some parachute material out and slowing her fall.

She’s very lucky, despite what’s likely to be a shitty next couple of years of rehab, but this isn’t a “fell from an airplane without a parachute and survived” miracle.

(1) https://www.lenouvelliste.ca/actualites/une-parachutiste-gra...

3 comments

Right so 300kmph = 83.3 m/s which means every 83.3 metres (call it 100) buys you an additional second of thinking time and back of the envelope calculation (2km/minute) [0] suggests you can move up to 33 metres per second horizontally (feel like this is optimistic - I openly welcome corrections here...)

In any case a fun thought experiment

[0]https://www.quora.com/What-is-the-average-horizontal-distanc...

There’s a joke in skydiving: “What happens if your backup parachute fails? You aim for the car of the person who packed it”
"For humans, no. After ~10sec you’re falling at terminal velocity" That means that falling higher will not increase your already slim chances of survival, and might well increase them, if ever so slightly. No?
Hard to say definitively - double malfunctions are relatively rare, so the sample size isn’t enormous.

More time can increase the likelihood that you can get some piece of parachute fabric above your head. And if you can do that, the odds go way up. There’s a saying I was taught on the first jump: “keep fighting until your goggles fill with blood.”

But if you cannot get a parachute out for some reason, a longer freefall will only give you more time to contemplate your fate.

I wonder if psychologically this ended up being a good thing. As in, physically the rehab might be bad but mentally.. it's bound to put things into perspective.