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by gresrun 1111 days ago
While I'm 100% positive the details of operational concerns like this are classified, there are 2 distinct types of submarines today with 2 different objectives:

1) Attack Submarines (e.g. Los Angeles-class & Virginia-class for USN) which usually roam within a designated operations area, surveilling, tracking, and generally keeping tabs on other nations' surface & sub-surface fleet dispositions. These subs typically have multi-week sorties and may intermittently surface for surveillance & comms.

2) Ballistic Missile Submarines aka "Boomers" (e.g. Ohio-class for USN) which are given a strategic area in which to operate and their objective is to remain silent & undetected, waiting for the hopefully-never-coming order to launch their SLBMs. These subs usually have multi-month sorties and often don't surface until the end of their patrol.
1 comments
ThinkBeat 1111 days ago
Clearly the Ballistic Missile Submarines surfaces intermittently surface for comms as well? If not, they won't know when to set off their missiles making then not very useful as a deterrent

I have often wondered how close to the surface they need to get.

I would presume retractable antennas could be extended from a sub from a non-trivial depth. Or cable attached to buoys Or something much smarter that I have not thought about yet.

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yencabulator 1111 days ago
There's a couple of different "wake up" signals that can reach deeper into water. Their biggest limitation is very low bandwidth, so an attack sub will emerge (/send up a buoy on a tether) to get an updated tactical map.

https://hackaday.com/2020/07/15/the-many-methods-of-communic...

https://en.wikipedia.org/wiki/Communication_with_submarines

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ethbr0 1111 days ago
Also highlighting the E-6B Mercury (and the upcoming EC-130J), which among other communication options has a 5-mile (!) VLF antenna it deploys vertically in midair (!!) to establish limited-bandwidth communications with submarines.

https://m.youtube.com/watch?v=en-qekZX4ws

But I believe that's only good down to ~60 ft. Anything deeper requires the really long land-based ELF arrays.

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