Invisible Force Sinks Sub

[PatB]

Originally Posted by captlloyd

I fail to see how an outdated fleet of worn out submarines is going to influence that scenario, surely they would be no match for what China would have.

Almost certainly true, but a Google of Malta WW2 will show that there are documented exceptions to the general equipment superiority = easy victory rule.

And, yes, I am aware that legend has somewhat embellished the truth of the Siege of Malta, but gthe early defence of the island with obsolete aircraft was still a fairly impressive achievement.

[AndyEss]

Originally Posted by captlloyd

I fail to see how an outdated fleet of worn out submarines is going to influence that scenario, surely they would be no match for what China would have.

Diesel-electric subs are not “obsolete”. Other than the superpowers, no country can afford nuke boats.

We throttled Japan with
diesel-electric boats operating 1000’s of miles from their bases. A regional power like Indonesia does not have any need to project power 1/2 way around the world which requires nuke boats for any efficiency and chance of survival.
Indonesia has every responsibility to militarily protect its sovereignty against any interloper.
Operations close to home bases don’t require nuclear kettles.

[AndyEss]

Polar Opposite - thank you for your service Sir.

The depth of persons on our Forum is outstanding.

[SeanPatrick]

Originally Posted by redneckrob

Just out of curiosity, was there really only one indicator of depth? Seems like madness, as a pilot we generally have at least one backup of the crucial instruments and I know the sub guys and aviators in the Navy have a similar culture around safety.

The way I read it, he was saying that one could fixate on the one depth indicator that was displaying incorrect information ... as opposed to the others that were correct.

[Polar Opposite]

Originally Posted by redneckrob

Just out of curiosity, was there really only one indicator of depth? Seems like madness, as a pilot we generally have at least one backup of the crucial instruments and I know the sub guys and aviators in the Navy have a similar culture around safety.

There isn't just one. On any sub there are at least two, maybe three depth detectors. They are kept to a minimum since they are penetrations in the pressure hull, creating weak points. They can also be cross-connected in case one breaks. If cross-connected, a single failure or sluggish response will affect all displays fed by that one detector.


But that's just one potential scenario. Another is a rudder or stern plane failure at high speeds. Another is a torpedo tube interlock failure (breech and muzzle doors open at the same time). Another is a double-ended sheer of a main cooling system line. Another is the main induction valve for the diesel failing to shut when submerging...and so on. There are hundreds of possibilities, some more plausible than others. But all more likely than a natural phenomenon.
There was one place we all knew about, entering or exiting the Med by Gibraltar. Because the Med is saltier and warmer than the Atlantic, there was a region of radically different salinity and temperature that created an underwater "wall" of dense water right next to "thinner" water. If you weren't expecting it, you could drive right over the wall and plunge a long way before catching it and correcting your trim.

[Polar Opposite]

Originally Posted by SeanPatrick

The way I read it, he was saying that one could fixate on the one depth indicator that was displaying incorrect information ... as opposed to the others that were correct.

Yep. More than one boat has had the guys in the engineroom call up to Control to ask what why they were out of depth band.

[warren5421]

If I remember right the last diesel boat in the United States service was decommissioned in 1990. Lookup Cutlass SS-478 Commissioned 17 March 1945 decommissioned 12 April 1973. G II refit 1948; struck and sold to Taiwan as Hai Shih 12 April 1973, reportedly still in service. I was stationed at New London Navel Base when the last WWII sub was withdrawn from service.

[Woodland Hills]

My guess is that, just like airliner fuselages, submarine hulls have a finite number of times/cycles that they can endure and this shows what happens if you exceed them. Long haul jets can be many decades old and still have lots of life left while a 737 on the NYC/DC run is all used up after just a couple of decades.
The aircraft industry can truthfully say that they have “never left one up there”, but submarines don’t always return to sea level.

[Woodland Hills]

Originally Posted by captlloyd

I fail to see how an outdated fleet of worn out submarines is going to influence that scenario, surely they would be no match for what China would have.

Every $ spent by China countering Indonesia’s diesel boats is a $ that cannot be spent elsewhere......

[captainjim47]

Clue #1. Any posting that uses the word invisible as an adjective for the word wave is b.s. Any "wave" capable of exerting any "force" is definable, unless you "believe" science is something that can be arbitrarily "believed in" or not...

[JPA Cate]

There ARE invisible forces: gravity and magnetism come to mind. Consider wind. We don't see them; we see the results of them.

Physicists would be more aware of these than this simple sailor.

Ann

[RaymondR]

A number of countries still use diesel electric submarines for coastal defense, they are generally smaller than nukes and much lower unit costs overall.

Since the mire significant loads on a submarine hull are compressive I doubt that they suffer the fatigue that pressurized aircraft fuselages do. Also they are generally welded and not riveted as most aircraft are.

[StuM]

Originally Posted by RaymondR

A number of countries still use diesel electric submarines for coastal defense,...

Some are planning to build new ones - and not just for coastal defence
https://en.wikipedia.org/wiki/Attack-class_submarine

[PatB]

Originally Posted by RaymondR

A number of countries still use diesel electric submarines for coastal defense, they are generally smaller than nukes and much lower unit costs overall.

Since the mire significant loads on a submarine hull are compressive I doubt that they suffer the fatigue that pressurized aircraft fuselages do. Also they are generally welded and not riveted as most aircraft are.

I'm not convinced welding is superior to riveting wrt fatigue/crack growth. Indeed the opposite tends to be true. In a riveted structure a crack cannot, by itself, extend beyond the edge of a single panel (although the increased load on adjacent panels may have a longer term detrimental effect, depending on the overall design). A crack in a welded structure, OTOH, can keep growing until the loads diverted around it become too great for the material to sustain and the whole thing unzips catastrophically. Quite a number of early welded steel ships fell apart for exactly this reason, until engineers fully grasped the issue.

I do agree, though, that significant crack growth issues are less likely in a structure subject to compression. I would guess (and it is a guess) that human error or system failure would be more likely as a primary cause of vessel loss than catastrophic structural failure, although, obviously, one could easily lead to I t'other.

Like others, although I'm not an oceanographer, I'm somewhat sceptical of an unusual (but, if extant, surely familiar to, and counterable/avoidable by submariners or more boats would have been lost to it) natural phenomenon being determined as the cause so soon.

Edit:I just noticed the bit about all the crew members "rolling down" if the sub angled downwards. Do we take it from this that the boat was a hollow cylinder without such things as handholds, bulkheads etc so everyone ended up in a heap at one end? Hopefully it lost something in the translation because, at face value, that sounds just a tad ridiculous as an explanation of anything.

[captainjim47]

Originally Posted by JPA Cate

There ARE invisible forces: gravity and magnetism come to mind. Consider wind. We don't see them; we see the results of them.

Physicists would be more aware of these than this simple sailor.

Ann

As a scientist I consider the headline to be juvenile and silly... you know, b.s. along with the article.