seamount

In 2005, the USS San Francisco collided with an uncharted (but suspected) seamount at 160m depth.

If Axial Seamount does blow, however, it won't post any threat human communities, experts say.

It happened again in 2021 when the USS Connecticut struck a seamount in the South China Sea, damaging its sonar array.

Moreover, the sub won't collide with the seamount as its precise location is now clearly visible on the sub's gravimetric equipment.

The prior NPR story on this said that the seamount (which they hit) was uncharted.

The US did the same for the San Francisco when she struck a seamount.

However the Brown Bear seamount does show up and is very close.

The San Francisco collided with the seamount at 160m depth.

The Foundation Seamount Chain in the Pacific might.

And likely of very limited value in underwater navigation unless you're in a research submarine literally hovering a few meters above some rocky metallic outcroping on a seamount.

The seamount should have been detectable.

[1] The depth of the ocean also differs significantly along the emperor seamount chain.

Yeah…sure…it hit a "seamount" – it's definitely not out-classed and out-matched by Chinese unmanned submarine drones.

According to there Tweet: "45 55.586N 129 58.7516W axial seamount, eastern side of caldera." It would also be nice to see things like depth.

"Radar is useless underwater." But sonar and detecting changes in gravity (caused by the higher density of the seamount) aren't.

Now that I think about it, though, a fully passive "seamount proximity sensor" is rather useful, and that's something you'd get even with a noisy signal...