tl;dr: Sonar buoys picked up sounds at 30 minute intervals. There is a relatively high probability that these are from the missing vessel, as producing sound by banging on the hull at the hour and half-hour is protocol for rescue signalling from underwater. Sound travels well where radar and other kinds of signalling does not. It’s also possible that the vessel is at or near the surface; sounds travel better in the same ocean layer, and the buoys are at the surface.
It’s also possible that the vessel is at or near the surface
NPR has someone on that had done the trip and said there are multiple systems in place to surface the sub in an emergency, including some that happen automatically. So there’s a very good chance that they’re at the surface, but still very hard to find because it’s a 20-ft sub in a huge search area. And they’re still running out of air because the hatch must be opened from the outside.
Interesting and terrifying. Assuming the sub is disabled somehow, is it possible for it to be stuck at a certain depth for a long period of time without sinking or floating to the surface? I always assumed it was an active process to hover between the two.
If those sounds are from the sub, the hull is still intact. Assuming that, I think it would be possible for the sub to not be resting on the bottom. That doesn’t necessarily mean that it’s at a stable depth. It could be sinking slowly until it reaches a depth where it’s neutrally buoyant, or the bottom. It could have already reached that neutrally buoyant depth, which could be the surface, or close to it. In any case, it would certainly be drifting.
tl;dr: Sonar buoys picked up sounds at 30 minute intervals. There is a relatively high probability that these are from the missing vessel, as producing sound by banging on the hull at the hour and half-hour is protocol for rescue signalling from underwater. Sound travels well where radar and other kinds of signalling does not. It’s also possible that the vessel is at or near the surface; sounds travel better in the same ocean layer, and the buoys are at the surface.
NPR has someone on that had done the trip and said there are multiple systems in place to surface the sub in an emergency, including some that happen automatically. So there’s a very good chance that they’re at the surface, but still very hard to find because it’s a 20-ft sub in a huge search area. And they’re still running out of air because the hatch must be opened from the outside.
They could also be stuck on something no? Those fail-safes assume you can float up
Interesting and terrifying. Assuming the sub is disabled somehow, is it possible for it to be stuck at a certain depth for a long period of time without sinking or floating to the surface? I always assumed it was an active process to hover between the two.
If those sounds are from the sub, the hull is still intact. Assuming that, I think it would be possible for the sub to not be resting on the bottom. That doesn’t necessarily mean that it’s at a stable depth. It could be sinking slowly until it reaches a depth where it’s neutrally buoyant, or the bottom. It could have already reached that neutrally buoyant depth, which could be the surface, or close to it. In any case, it would certainly be drifting.
I’d imagine you can triangulate the sound with an array of sonar buoys if it is on the same ocean layer?
Edit: commented before reading the article. That’s exactly what they’re planning. 🤦♂️