[pifm_guy]

False negatives are more worrying. On a small speedboat, a common cause of death is that the captain falls overboard while the boat is doing a sharp turn at speed. The boat then does a 360 circle and within 10 seconds runs over the captain before anyone else in the boat can intervene.

Will these wireless keyfobs reliably cut out within 10 seconds when the boat never goes more than say 60 feet from the captain? I suspect not.

[burnished]

Would a wired one that went unused prevent that? That would seem to be the core problem in your scenario - the existing technology that would not have a false negative here is going unused.

Also, can you cite any sources for that event being common (relatively at least)? Not that I doubt you specifically, the scenario is just so horrifying that I am generally having trouble accepting it.

[LeonB]

The accident described above is basically the same as happened in my hometown in October 2021. There was no one else in the boat but many witnesses on the shore. The whole community greatly affected.

https://www.couriermail.com.au/news/queensland/rockhampton/a...

[pifm_guy]

Here is a news report with video footage of one such incident (the part where the victim is decapitated is clipped from the report): https://youtu.be/3IwhsYfnNvs

I am personally aware of quite a few speedboat related accidents, some fatal, and this is a common pattern.

The types of death that people imagine (boat sinks, boat engine dies and drifts out to sea) tend not to be killer in small boats because they mostly operate in busy waterways near shore where someone else will come help.

[sgtnoodle]

Radio waves propagate very poorly in water compared to air, so there's a good chance that the signal is lost as soon as the wearer falls in. From there it's just a matter of how long the timeout is, and the latency of cutting the engine.

[eternityforest]

Is there a reason people can't just have seatbelts of some type for that?

By the inverse square law accuracy should be better at close range, cutting out at 10 to 30 feet but not 0 to 6 feet should be possible, especially with UWB, and even moreso if the fob detects water directly.