In the tradition of submariners you’ll notice a certain silence on certain topics from him. Things unmentioned seem to be unmentioned deliberately.
There also seems to be large “cones of silence” around what seem like pretty trivial factoids. So you won’t get very close to piecing together an answer from a collection of tidbits.
The answer (for US subs currently or recently in service) may be classified. I should know (since I served on a sub) but I don’t remember exactly whether it’s classified or not (but I do know the answer to the OP question).
You’re welcome for this extremely helpful answer.
I wonder what kind of interesting and/or scary sea creatures it found down there.
Only for about 20 minutes, IIRC.
As a naval machinist’s mate, I have always assumed that subs sitting on the bottom only did so in dire circumstances, where the boat was dying or in extreme danger.
There are so many fittings and vents that could get clogged, as well as bottom suction and unpredictable terrain. I can’t imagine this being a normal activity.
As an aside…
This question reminds me of when I asked one of my instructors in nuke school if one could roll a sub. He rolled his eyes at me and said something like “I can assure you, you cannot roll a sub”
Just the smallest bit of consideration of the mechanical systems involved made it clear to me why: As one simple example, the condensate in the hotwell under the main condenser would wash over the turbine blades, destroying the main engines. The eye-roll was well deserved.
Not to mention, the keel & outer hull might not be able to support the sub’s weight and could buckle/crumple even if the ground itself isn’t too rocky/jagged
I agree and just to slight further clarify, old fashioned ‘ship shape’ subs had more righting moment on the surface due to shape all else equal, but there’s no righting moment from shape for any fully submerged sub. For a submerged sub the center of gravity has to be lower than the center of buoyancy, as opposed to conventionally shaped surface(d) vessels where the center of gravity need only be lower than the ‘metacenter’ about which the ship rolls, which is higher than the center of buoyancy to a degree depending on hull cross section dimensions and shape. But it’s easy enough for a submerged sub’s center of gravity to be below its center of buoyancy: put heavier stuff lower in the boat, including permanent ballast if necessary.
The intuition that a cylindrical hull sub is top heavy because of the sail is, like the similar common impression of modern cruise ships, based on the implicit assumption of homogeneous density, but that’s far from true.
Subs in the world wars fairly frequently lay on the bottom. Only a small % of the world’s oceans are shallow enough to do that, especially for the couple-few 100’ depth capability of those subs, but a disproportionate % of submarine combat operations occurred in those waters, though still not most. When subs did that though, if not for emergency repairs or operating on a crewman or something, it was usually to save battery where it wasn’t safe to come to the surface. It was to try to get the pursuers to give up or a routine patrol to move along.
A nuclear sub, obviously, doesn’t have to worry about battery charge and isn’t likely to be significantly noisier moving at slow or even not so slow speed than lying still. A public claim about the US Virginia class SSN’s for example is that they are as quiet at 25kts as the earlier Los Angeles class is sitting still. So aside from secrecy aspects, it’s hard to see a lot of situations where SSN’s would place themselves at a tactical advantage to lie still in water shallow enough to do so, and there are risks as mentioned.
But in some cases nuclear subs sat on the bottom at least for special missions specifically requiring it. The book “Blind Man’s Bluff” gives an account of USS Seawolf sitting on the bottom in the Sea of Okhotsk in 400’ of water in 1981 operations to tap Soviet communications cables. The condenser silted and the boat got stuck by the suction of the bottom (a problem for WW’s subs also in some cases per a number of accounts) for two days, barely limping back to open water, according to that account.
Both *Halibut *(SSN-587) and *Parche *(SSN-683) were both very interestingly outfitted for the missions they performed, to include servicing the equipment for Operation Ivy Bells. *Halibut *is said to have had hull fittings specifically for the purpose of sitting on the bottom. It’s not unreasonable to think her replacement (Parche) had them as well.
Blind Man’s Bluff is an incredible book, detailing a small piece of some of the most… interesting… Cold War missions ever undertaken by the US. I highly recommend it if you’ve got an interest in this sort of thing.
Thanks guys!
I now have another Audible book in my queue for when I am out on a run.
I’m currently deep in the battle in “The Last Stand of the Tin Can Sailors: The Extraordinary World War II Story of the U.S. Navy’s Finest Hour” (an excellent book as well).
Once that one is finished I’ll start on “Blind Man’s Bluff”
The description of the USS Jimmy Carter sounds like something from a James Bond movie. Also appropriately named. Very cool, thanks for the link.
About a third is less than 200 meters. 300 meters was supposedly max for a WWII Uboot, but their rating for was half that.
700 meters or more for a US Nuke boat.
I think there is a distinction between touching the bottom and completely resting a lot of the sub’s weight on the seabed. After all, a sub is designed to change its buoyancy so there can be a wide range of force here.
Touching the seabed I can see, but really letting go of a lot air and pressing down hard on the seabed. Is that doable? Are the bottom hulls designed to handle a lot of weight (especially with an uneven sea floor)?
One third (or a bit more) sounds like the portion of the earth’s surface less than 200m below sea level, including land above sea level. Around 8% of world ocean basins (oceans and adjacent seas) are less than 200m deep. As I said though, submarine combat ops in the world wars were somewhat disproportionately concentrated in shallower water. In fact subs’ targets might attempt to stay, if possible, in water not only shallow enough for the sub to reach bottom but too shallow for it to safely submerge at all, and shallow enough to establish defensive minefields.
Modern US nuclear sub test depths are given in “Combat Fleets” as 300m (Ohio SSBN) to 594m (Seawolf SSN, 488m for Virginia’s 450m for Los Angeles). Like the WWII figures (and assuming these are even the actual official design figures) it’s not the absolute max which might be more like what you said. However it’s probably a reasonable estimate of how deep the sub would deliberately go to bottom in normal operation if that were a common tactic, though it probably isn’t for reasons already discussed. About 12% of ocean basins are <1000m deep.
Only Ocean Racers? Sailing dinghies do not use weighted keels. Actually, I think none of the Olympic sailing classes use weighted keels.
Minor hijack: Definitely an excellent book – strongly recommended for anyone interested in WW II and/or naval operations. I got Neptune’s Inferno: The US Navy at Guadalcanal, by the same author, for Xmas, though there a few other books above it in my TBR pile…
I met a veteran at a 7-11 wearing a baseball cap that read “Kamikaze Survivor”.
I mentioned that I had read The Last Stand, and remarked how brave these guys were to take on capital ships. He responded, “That’s what destroyers do.”
True, but besides the point. A submarine out in the deep blue sea is more or less unfindable. The problem (for the bubbleheads) is that their covert operations don’t take place in the deep blue sea, by and large. Whether it’s spying on port facilities, inserting or extracting commandoes, mining straits, it all takes place on top of the coastal shelf. In turn, most of a country’s antisub contingent is patrolling their coastal shelf because that’s where the stuff wot needs protectin’ from enemy submarines is. The rest are out and about around the country’s blue water navy, and good fucking luck to them 'cause these days the first clue they’ll get there’s an enemy submarine somewhere within 40 nm is a rapid exothermic reaction suddenly being released right under their feet.
Not sure how it’s besides the point of a post saying 1/3 of the oceans are less than 200m deep. 
But as I said, twice, submarine warfare has historically been conducted disproportionately in relatively shallow water. A distinct majority of the 1,000’s of ships sunk by submarines in the 20th century were in water too deep for the attacking submarine to lie on the bottom, but not as high a % as deep areas represent in the whole ocean. Also somewhat depends which sub fleet in question and when. Submarines operating in the Baltic say are going to encounter lots of shallow water, ones conducting the envisioned missions of US nuclear subs in the Cold War much less so; SSBN’s always less so.
In the post CW period the US SSN fleet had put more emphasis on missions in shallow water, for fear of lost relevance and therefore lost funding, though missions like landing commando’s really don’t play to the strengths of those big and extremely expensive subs, US subs don’t have have mines anymore (retired) and can attack land targets with long range missiles as easily from their natural habitat in deep water. However with a rising peer threat from China and Russia the US SSN fleet can go back to justifying its existence with an offensive antisubmarine mission which plays more to its strength, and perhaps eventually a serious anti-surface mission again, in addition to long range land attack.
As to how vulnerable ships are to submarines and submarines to ASW, that like a lot of other this v that questions in naval warfare is increasingly difficult to answer with just tests, exercises, and a few small scale real naval wars: no major naval war in over 70 years. It’s good if sub commanders have confidence in the ability of their boats: an excessive belief in the likely effectiveness of enemy ASW, caused by artificial prewar exercises, was among the factors (besides torpedo problems) hobbling the USN sub force early in the Pacific War. But unpleasant surprises from the POV of subs against top adversaries can’t be excluded: those potential nasty surprises pretty much by definition are not included in exercises where subs end up taking ‘gotcha’ periscope pictures of friendly targets.
Waitaminit. Machinery gets service awards?
Those first three awards (NUC, MUC, and Battle E) are specifically awarded to the ship, and are worn by personnel who were part of the ship’s crew during the time period the ribbon was awarded for. The other three work the other way – they’re awarded to the members of the crew, but are then considered to have been awarded to the ship as well.
USS Iowa (BB-61).