
Modern submarine torpedo attacks are not like in the movies - smacktoward
https://www.thedrive.com/the-war-zone/33018/modern-submarine-torpedo-attacks-are-nothing-like-what-you-see-in-the-movies
======
sandworm101
Take EVERYTHING in that article with a giant tub of salt. The specifics of
torpedo combat are some of the most closely guarded military secrets.

Take the following: "These high-torque, permanent magnet electric motor
torpedoes ramp up to speed in under a second. They go from sitting in a
torpedo tube to 50 knots in a near-instant because they don’t have the
mechanical lag and inertia thermal torpedoes must overcome during startup. "

So much of that is totally wrong. The torpedo has nothing to do with how it
gets out of the tube. Its propulsor (not a propeller) wont work from the back
of a torpedo tube. Starting it up in the tube, INSIDE the sub, sounds horribly
dangerous. The torp is ejected by force from the sub _and then_ starts its
engine. Electric or thermal, it's doing 50+ whether it wants to or not. Once
out of the tube, further acceleration potential is limited by depth/pressure.
All torps have more than enough torque to start cavitating their propulsor in
shallow water. To continue to automotive analogy, it doesn't matter whether
your car is electric or turbine powered, acceleration is limited by how much
power your tires can handle before spinning.

[https://www.youtube.com/watch?v=PjoholiW1ho](https://www.youtube.com/watch?v=PjoholiW1ho)

And this is why you don't want that engine running prior to the torp leaving
the tube.

[https://www.youtube.com/watch?v=KoElLaLcfOc](https://www.youtube.com/watch?v=KoElLaLcfOc)

~~~
jfoutz
Very tangential question.

I can think of only a handful of targets that the US might want to shoot at.
(I realize there might be a ton, and this is my lack of imagination). The
handful I can think of, almost all of them seem like they're in the supply
chain to actually build the torpedos. I'm pretty skeptical of the depth of the
US stockpile.

To put it another way, if there was a war so bad, the US reinstituted the
draft, would these tools still be relevant? The US industrial base is mighty,
and could certainly retool to meet whatever need arises, but that'll take
years.

Really seems neat, but after you've taken your 20 or 50 or whatever shots, how
do you resupply? Seems like you'd need special coatings or shelf stable
chemicals or a hundred other things to make the super fancy weapon.

it sure _seems_ like (although I have no fucking clue, so I'm asking) the
super fancy weapons are available for a few weeks if things get real bad.

_edit_ realized I didn't actually ask a question. Can the US actually build
these things from, like, minerals? It's a big country, we have them. The
industrial base doesn't seem tuned for actually doing that though.

_further edit_ I'm a very silly person. it seems like the only _must have_ is
a plausible second strike capability. It's great to be able to protect the
free flow of oil, or defend the Kurds from chemical weapons. Hell, one of the
most American things I can think of is protecting yankee clippers for safe
trade. It's part of the Marine's Hymn. but clearing pirates from the shores of
Tripoli isn't absolutely vital. I'd sort of thought that subs jobs in the
modern world was making sure that if the US can't play, no one else can
either, with moderately sized nuclear weapons. Again, I'm a very silly person.
The question with the further edit is, do subs have an essential job beyond
second strike cabability?

~~~
londons_explore
> To put it another way, if there was a war so bad, the US reinstituted the
> draft, would these tools still be relevant?

The drafted people would all go to factories and boatyards to build thousands
of new submarines. Each submarine would likely have _no_ people on board, and
be fully remote control.

The age old problem of "you can't hide while sending and receiving data, so
you can't make a drone sub" has been solved by using below-noise-floor gold
codes, so without the coding key, nobody can even tell a transmission is going
on.

~~~
tuxxy
I'm a cryptographer, so I'm inherently curious about secret communication. It
just so happens that I'm also very curious about radios, satellite
communications, etc.

Do you have a link that provides more information on these "below-noise-floor
gold codes"? I tried googling, but I haven't found much technical information
that I trust is entirely truthful or relevant.

~~~
londons_explore
The principle is that if your ally has a receive antenna with a gain of X, and
you use a modulation scheme with a coding gain of Y, and you transmit strong
enough that your signal can be received by your ally with a snr margin of Z,
then as long as your enemy doesn't have a receive antenna with gain > X+Y-Z,
they can't detect your signal from the noise.

Since Y can be increased arbitaraly (at the cost of channel data capacity),
it's always possible to transmit some information to your ally without your
enemy seeing a transmission, it might just be a few bits per second, but
theres a lot you can do with a few bits per second in warfare.

One needs to make sure that the above holds true for all possible frequency
windows and time windows, so no carrier waves or high power sync pulses!

I believe the implementation is much harder than the theory - just one crystal
oscillator or PLL anywhere in your radio hardware will leak some of that
frequency into the output, and since the bandwidth of a crystal oscillator is
super low (obviously an ideal oscillator has zero bandwidth), even a tiny leak
is detectable by an enemy.

------
neurobashing
Somewhat related, my uncle was a “Phantom driver” (F4 Phantom II) in Vietnam.
Flew a bunch of missions of varying types.

So Top Gun comes out, and my mom points out he had graduated Fighter Weapons
School - my uncle is a real Top Gun!

So I asked him for tales of dogfights, war stories. He had exactly one:
“they’d send us out to fight some MiGs, and as soon as we got in range and
turned our radar on to start shooting, they’d turn and run.”

So not like the movies?

“Nope.”

~~~
phkahler
Recently saw an old video on youtube about that. Top Gun was created in
response to heavy losses in Vietnam. It was very small and they had trouble
even finding space for classes. A turning point came when a Mig was captured
and they trained with it to find weaknesses. After that everything changed.
The kill ratio inverted and they did start to run when engaged in some cases.
Your uncle was lucky to go after the strategy was worked out, or he probably
wouldn't have come back!

~~~
kitteh
Have Doughnut and Have Drill were the govt programs (which have been
declassified) where we used acquired MiGs to learn their weaknesses. There are
some great videos on YouTube and books from people who were directly involved
in the Red Eagles.

~~~
erentz
Any history on the use of the word “Have” in project names like this? I’m
thinking of “Have Blue” also but didn’t realize it seems to be a theme. It’s
always sounded weird as hell to me.

Edit: oh I found something to answer my own question:
[https://www.globalsecurity.org/military/systems/aircraft/f-m...](https://www.globalsecurity.org/military/systems/aircraft/f-missing.htm)

------
m4rtink
You mean like how torpedoes actually detonate when they hit a target in a
movie ? ;-)

[https://en.wikipedia.org/wiki/Mark_14_torpedo](https://en.wikipedia.org/wiki/Mark_14_torpedo)

Or how in the movies they don't run in circles and sink the submarine that
launched them ?

[https://en.wikipedia.org/wiki/Mark_18_torpedo](https://en.wikipedia.org/wiki/Mark_18_torpedo)
[https://en.wikipedia.org/wiki/USS_Tang_(SS-306)](https://en.wikipedia.org/wiki/USS_Tang_\(SS-306\))

~~~
chiph
Or they sink a truck?

[https://youtu.be/GpEcU0OEzhc?t=120](https://youtu.be/GpEcU0OEzhc?t=120)

------
kragen
How is there an article entitled "modern submarine torpedo attacks" apparently
written in 2020 that doesn't contain the word "supercavitating"?

[https://en.wikipedia.org/wiki/VA-111_Shkval](https://en.wikipedia.org/wiki/VA-111_Shkval)

~~~
Arubis
Somewhat cynical take: because the West doesn’t have superiority in this
space.

~~~
ckozlowski
These got a lot of attention a while back. But their use case is limited
because they're really short-ranged. These things go all out soon after
leaving the tube, make a hell of a lot of noise, and are good only really
close in. They're sort of a last resort weapon, a snapshot provided that the
enemy shooting at you is even within range.

A modern US Mark 48 can swim out quietly under wire guidance and emit no noise
or sensor emissions, steered on an intercept course, then revved up to top
speed once it's in close. A torpedo like the Shkval can't close the distance,
and that's assuming the enemy even knows where they're being shot from. Just
because a Mark 48 suddenly goes active on your stern doesn't mean it was fired
from there.

According to the wiki article, this was for intercepting incoming torpedoes. I
suppose that could work, though again, the noise I'd imagine would be
troublesome. It might mask for you a bit, but your attacker would know where
this thing was shot from. Meanwhile, your own sonar is only going to hear this
thing, meaning you've lost a solution on the guy shooting you, leaving him to
set up again.

I highly suspect the reason we haven't seen an equivalent is because the
tactical doctrine doesn't call for one. My armchair two-cents.

~~~
jacobush
My personal theory is that a big use case for Shkval is in the littoral and
shallow waters of the Baltic Sea where there is fantastic opportunity to play
hide and seek. Especially sub to sub. I think the Soviet command expected
enemy subs to successfully sneak up on them and then have something up their
sleeve to raise hell right back.

~~~
kragen
For that kind of case, wouldn't it make more sense to keep the torpedoes
deployed all the time at 100 meters or so from the main sub, so that they can
counterattack after it gets destroyed? It could drag them behind it on cables.

~~~
jacobush
In shallow, litteral waters full of all sorts of junk and varied topography?
... maybe not.

~~~
kragen
Yeah, I was thinking of the deep-sea case, despite the context given above.
Wouldn't do to have a dozen torpedoes all sending out sonar chirps!

------
alanbernstein
A misconception I had was that submarines fight each other under water.

[https://en.m.wikipedia.org/wiki/German_submarine_U-864](https://en.m.wikipedia.org/wiki/German_submarine_U-864)

"It is the only documented instance in the history of naval warfare where one
submarine intentionally sank another while both were submerged."

~~~
ubermonkey
Not for nothing, but have there BEEN many submarine engagements since WWII?

Is current doctrine that, say, fast attack subs would shoot at opposing
boomers from underwater? I mean, it seems likely, right?

~~~
jki275
Not a submariner, but I always thought that was the essence of the existence
of the fast attack.

------
deanCommie
Outstanding article, very informative, but the tense and tone is slightly
amusing to me:

> Actual underwater combat occurs silently with very little reaction time to
> fend off an impending attack.

Does it occur? Do we have any examples of "actual underwater combat"
occurring? I don't believe we have any real life examples of nations withs
submarine capabilities in combat. War games probably don't count...

~~~
angry_octet
RIPLEY How may drops is this for you, Lieutenant?

GORMAN Thirty-eight...simulated.

VASQUEZ How many combat drops?

GORMAN Well...two. Three, including this one.

------
cafard
Has any ship been torpedoed by a submarine since the Admiral Belgrano in 1982?

~~~
mhh__
Minor Nitpick, it was the General Belgrano

[https://en.wikipedia.org/wiki/ARA_General_Belgrano](https://en.wikipedia.org/wiki/ARA_General_Belgrano)

~~~
cafard
I just upvoted you. I can only say it has been a while...

------
supernova87a
Side question -- do submarines really have the ability to ping, like in Hunt
for Red October, do they ever use it, and does it actually use the frequency
range of human hearing like that? Do torpedoes? Or are they ultrasonic (given
that depth gauges I know are ultrasonic). I assume that subs once did use such
pings historically given how common that sound effect is associated with them.
Maybe not any more I guess?

~~~
dylan604
The thing about the ping is that everyone that can hear it gets the benefit of
that ping. So you are 100% giving away your position with a ping. Nowadays,
you want to stay silent, so you use passive sonar. A very long tail is trailed
behind the sub with lots of microphones listening. They've done it so long,
they know what all sorts of things sound like. Man made objects likes subs and
surface ships, airplanes flying above the water, rocks sliding, crabs
crawling, etc.

~~~
waste_monk
My (admittedly very armchair) understanding is the ping is a lot worse for the
hunter than the target - the distance you can hear the ping is roughly 2x the
distance* you'll get a useful return from it, so if the target is beyond that
range you'll effectively lose all stealth and confer a huge advantage to the
enemy.

* this is complicated by thermal layers, geography, etc. but very approximately 2x is the figure I've heard.

------
vanderZwan
> _With command wire capabilities, the weapon can change its attack geometry
> or even shut down if directed by the fire control operator. Detected targets
> can be changed, depth and range limitations can be set, and countermeasures,
> such as decoys and jammers, can be ignored using the submarine’s sonar data
> instead of the torpedo 's lower-fidelity onboard sonar data. If the data
> link is lost, the weapon will follow its last given command and execute pre-
> programmed countermeasure defeating profiles, if necessary._

This somehow reminded me of the final scene from John Carpenter's Dark Star
(spoilers, obviously) where a smart bomb wants to blow up (yes, you read that
right), and the crew has to talk it into not doing so by using philosophy to
give it an existential crisis:

[https://www.youtube.com/watch?v=h73PsFKtIck](https://www.youtube.com/watch?v=h73PsFKtIck)

------
1123581321
“A torpedo cannot be ‘command-detonated’ as seen in the movie Hunt for Red
October.”

Why is this so? The wire controls seem sufficient.

~~~
reddog
That is odd. I know that during the war in the Pacific the Japanese were
_extremely_ careful to avoid having the vastly superior longlance torpedoes
fall into the hands of the Allies. They would go to great lengths to search
for and recover lost, unexploded torpedos that were in shallow water. It seems
like a command-detonation options would be very useful in this regard.

~~~
dbcurtis
Well, I can guess at a few reasons. 1. As mentioned elsewhere, the radio
signal path loss through salt water is astoundingly high -- I did the math
once. 2. WW II era radio technology was bulky, and did not work well on
batteries -- vacuum tube filaments eat a lot of power and the plate supply
requires a high voltage battery. 3. WW II era radio technology did not have
encryption built-in -- it would have been pretty easy for the enemy to signal
the torpedo to blow up before you launched it, which would kind of ruin your
afternoon.

------
tim333
The most in recent serious submarine attack, the sinking of the Blegrano they
decided to skip the fancy homing missiles due to unreliability and fired three
non-guided torpedoes so it was a bit like the WW2 movies.

------
AtlasBarfed
I rip on surface fleets as being floating reef fodder that would be sunk
almost immediately against any modern power, either because of the
sophistication of submarines, the rise of cheap drones winning the economic
exchange, or death-from-above missles and ICBMs that are basically
undefendable.

But against subs I'm surprised there aren't plans for a drone-net that
surrounds a fleet or high value ship that can detect incoming underwater
threats via some mesh networking.

~~~
magicsmoke
Smaller drones have weaker propulsion and can't keep up with the ship its
supposed to provide a detection bubble around. Being underwater and having to
deal with additional drag also doesn't help. The large size of an aircraft
carrier belies the fact that it is the fastest ship in the carrier group and
can outrun all of its escorts. Larger ship = more space to pack powerful
engines.

That's also a major issue for a lot of other drone swarm schemes such as using
drone swarms to counter fighter aircraft. Smaller drones don't have the
propulsion to keep up with fighters, and once you make drones large enough to
hold the engines that would let them keep up with a fighter you might as well
build a fighter instead.

~~~
contingencies
There were networks of deployable remote surveillance buoys being developed by
the 1990s. Source: Public research reports of military research organizations.
Presumably removing the propulsion expectation simplifies the problem domain.

~~~
AtlasBarfed
So they were deployed but then abandoned?

I wonder if you could have a flotilla of heli-drones that drop in sampling
microphones/active sonar. Wind might be hard to deal with in storms or heck
even typical conditions.

------
nabla9
When you store unguided torpedo inside capsule in the bottom of the ocean, or
allow it to float in some predetermined depth, you have Torpedo mine, like
CAPTOR.

You don't need expensive submarines, if you want to protect narrow points or
specific areas. You just drop torpedo mines underwater.

------
tra3
Never occurred to me that torpedoes can be battery powered. Any idea what kind
of cells they have?

I got confused by the dual units here:

> 65cm torpedoes have enough fuel to travel in excess of 100 kilometers at 50
> knots for just over an hour.

Turns out 1 knot/hr is nearly 2km/h so that checks out. Weird nautical units.

~~~
soneil
So fun trivia. A nautical mile is one minute of latitude (1/60th of a degree).
The meter was originally 1/10,000,000th of the equator to the north pole. So
I'd argue the nautical mile was more logical than the statute mile, in this
respect.

This is also why you can rough 1knot:2km; you're dividing those 10,000,000
old-world-meters by 5400 (90°*60').

~~~
dylan604
If you use a 7200rpm hard drive does the math work out differently?

I always forget the definition of the nautical distance. Thanks for the
reminder. There's also the knot in a rope every certain distance that would
get counted against a stop watch to see how fast the ship was moving.

------
tzs
> The batteries are connected in series allowing each weapon to have 2, 3, or
> 4 batteries. More batteries give the weapon more range. Fewer batteries make
> the weapon much lighter and more agile, but at the cost of range.

This sounds wrong. Shouldn't they be connected in parallel?

~~~
angry_octet
I think we can take this as an explanation for generalists, rather than a
problem set from basic EE.

------
bryanrasmussen
I think it would be more interesting to have a list of things that are like in
the movies, as I assume it would be a lot shorter than the list of things
unlike, and rarity is in many things considered more important than the
common.

------
qwerty456127
Does anybody even attack submarines nowadays? Isn't the sole purpose of a
torpedo - to make the opponent believe they better avoid attacking you?

------
mothsonasloth
The article misses out on other forms of submarine attacks, like anti ship
missiles (harpoon) and ballistic missiles.

------
hoseja
Wonder how much of this will translate to space combat.

------
redis_mlc
Favorite article comment:

"I love these _deep dives_ on a topic."

