The Navy Thread

It was technically viable from the start, but not practical. It became common once more advanced targeting systems were available.

Most torpedoes during WW 2 could keep a straight line and nothing else, and they had to be targeted visually. The sonar systems available also weren't great. Obviously it's hard to see another submerged sub from your sub, so making that shot was essentially a game of chance.

Immy: The first attempts at deliberately built subs to hunt other subs began pretty much after WWII ended with the US designing a sub built to look for other submarines with the Barracuda class. The big change here was the built in use of passive sonar in the bow rather than relying on hydrophones. Even then it wasn't until nuclear subs came around that any such efforts really took off along with various other technological changes including steady improvements in guided torpedoes. The first generations of guided torpedoes had some notable teething issues.

These assorted advances would allow the subs to actually look for submarines that weren't running at or near the surface with some sort of surface presence like a periscope or snorkel. Which is how the British found, tracked, and fired on the German sub by spotting their snorkel. Nuclear powered subs were a huge boost in submarine capability which pretty much guaranteed that the attack subs would need to follow suit and use ever improving tech as subs could run under water with almost no surface presence at all and run at depth for extended periods of time.

edited 1st Jun '18 5:15:35 PM by TuefelHundenIV

I was never questioning the deliberateness of the action, but your original post on the subject of of sub vs sub was that the sinking of U-864 was the only time a sub sunk another sub. Not the only time that it happened deliberately, but the only time, period, and the qualification of "deliberate" is straight-up goalpost moving.

edited 2nd Jun '18 12:05:56 AM by Balmung

No I am not moving the goal post that is what I meant, I did not state it clearly that is my fault.

A couple of thoughts:

I doubt the Type 93 burned pure oxygen, given that oxygen isn't flammable. It is, however, as the name suggests an excellent oxidizer, meaning it's great for setting other things on fire whether you want them to catch fire or not (hence why most fire extinguishers work by starving fires of air). Wiki says the torpedoes actually ran on methanol or ethanol usually.

Japanese destroyers being basically big torpedo boats: That is more or less how destroyers came to be. Giant Mook torpedo boats designed to engage and outgun enemy torpedo boats to protect their capital ships. Arguably all modern surface warfare ships (mostly destroyers and frigates) are simply even bigger torpedo boats, with the development of anti-ship and anti-air missiles.

Subs as anti-sub vehicles: The main barrier historically to subs hunting other subs is that subs are both hard to see and tend to operate in a position that gives them notoriously poor visibility of the battlefield (ever see a submarine with a crow's nest for lookouts?). The development of SONAR obviously changed this calculus in a big way.

They used pure oxygen as oxidizer, which greatly increased the range for the same fuel weight and left mainly carbon dioxide as exhaust products thus very few bubbles in its wake owing to the easy solubility of carbon dioxide in water.

They were long ranged and very stealthy compared to its contemporaries. Hence why some ships that were hit by them thought they ran into mines.

Nav Weaps notes the propulsion as Kerosene-Oxygen Wet Heater.

edited 3rd Jun '18 1:55:41 PM by TuefelHundenIV

Yea, it was the oxidizer specificly that was pur oxygen, and that is why the damn things were so explosive once fueled up.

Because any amount of oil left in the pipes, or somewhere in the torpedo would just.... ingnite.

It was such a thing, that funnily enough the janitor was considered to be one of the most important jobs, not just a punishment or low rank possition, on IJN ships, because those pipes had to be perfectly clean.

edited 3rd Jun '18 2:21:42 PM by Imca

The IJN -Almighty Janitor: I need keep this shit clean or we all die, so bugger off and let me do my work.

To be fair, I'm sure the janitor who had to scrub the head wasn't the same guy as the janitor who serviced the weapons.

This is the IJN, I wouldn't be surprised if they only had one dude per ship

A master janitor who trained for three years in the cleaning arts.

Meanwhile, the US Navy would just recruit a few hundred guys, give them mops, and assign some Petty Officers and Chiefs to figure out the details.

Also, regarding the sailors thinking they'd struck a mine, one of my favorite bits of trivia is that torpedoes get their names from an electric ray which would lie stationary and zap anyone who came close. The original naval torpedoes were actually sea mines.

Torpedo boats would drag the mines past enemy ships, then later ones mounted them on a spar to ram into the enemy ship, and eventually they basically just attached the boat engine to the mine and sent it off like an Attack Drone.

edited 5th Jun '18 3:36:30 AM by AFP

The spar mounting turned out to be a bad idea. There is some good evidence that the Confederate submarine that used that tactic wound up being killed by the shockwave of their own weapon.

The loss of CSS Hunley is seen as a combination of factors, the spar torpedo not being a help in any of them.

Between evidence that the spar torpedo went off at an improper time, CSS Hunley herself not being built to snuff to handle the mission/explosives (poor design, poor steel, etc.), the possibility of Union troops sighting and firing upon her (there is at least one account of a Union lookout aboard USS Housatonic spotting Hunley) and potential mechanical/crew failures that doomed the boat even if everything else went off without a hitch, it wasn't just a single point of doom.

The submerged bucket of suck.

And yet, the most successful Confederate torpedo boat of the war, as far as I know. A quick Wiki seems to suggest only one other torpedo boat, CSS David, laid in a successful attack, and even that one only wounded her target (USS New Ironsides), and David's boilers got put out by the column of water from the explosion, leaving her adrift immediately next to the people she had just previously attempted to blow up.

The crew managed to get the boilers going and made tracks before the Union squids could sink or capture her.

Another factor for the development of self-propelled torpedoes might be the fact that ships began getting armored around the same time spar torpedoes came into vogue around the same time as ironclad warships. Given the literal potential for the torpedo boat crew to be hoist by their own petard, equipping torpedo boats with more powerful warheads presented some obvious engineering problems.

edited 6th Jun '18 1:24:14 AM by AFP

^ There was also the matter of the increasing range of naval guns. In 1861 a spar torpedo was perfectly fine, naval guns could maybe on a good day with the wind at its back hit 1000 yards and definitely not accurately from the deck of a ship. By 1865, 1000+ yards shots were possible owing to improvements in guns, ammo and powder.

Forty years later, if your battleships couldn't hit in excess of 15 miles, you were in a world of suck.

Self-propelled torpedoes allowed small craft to have enough range that they could fire on enemy ships from a sizable distance while not being the size of dreadnoughts ultimately.

Tom: Actually you are actually only describing effective ranges for the oldest guns used and even then the bulk of the artillery used both on land and shore could fire further than 1,000 yards. By the time of the American Civil War increasingly larger and more powerful guns which reached a few thousand yards further had already been in use on the largest sailing ships, earliest iron clads, and steam ships. The smooth bore guns could hit out to an average of about 3,500 yards. The rifled guns with calibers smaller than their smooth bore counterparts in several cases could in several cases double that range. This was also the era where a sharp increase in explosive shell with more than just a timed fuse was starting to be seen. Some of this artillery was developed and used during the same period of the Crimean War. This was an era where artillery saw a lot of rapid changes just prior to the first World War.

edited 6th Jun '18 10:05:41 PM by TuefelHundenIV

How much munitions were about aboard WWII carries, roughly how many times could the atack groups be reloaded?

edited 9th Jun '18 4:02:41 PM by Imca

Quite a few. Such that carriers could bombard targets for literally days before needing a stock up from the supply ships. For example Peleliu, Navy planes from carriers bombed the crap out of the airfield there for 3 days before the Marines went ashore.

Unlike a battleship duel which had a hard maximum of a few hours firing at most before the ships ran dry. carriers had some longevity.

This was also a double edged sword. All that ordnance meant if a carrier took a good hit, it might brew up from stem to stern. (The Big E, USS Enterprise had such a thing happen to it but she ultimately survived it.)

I mean, that makes sense given a flat top is basically just a giant floating werehouse, but did the same apply to our catriers?

I ask mostly because the primary weapon of an IJN carrier was the Type 91, which I think would take up more internal volume then the 1000lbs bomb.

Immy: I recall the situation being similar for Japanese carriers. I can't recall which one but it ate two or three penetrating large bomb hits that ignited fires and munitions below decks and it caused quite a mess. While the Japanese did pursue different design ideas the basics of carrier combat were more or less the same in that the ships carried fuel and munitions stores for several sorties at least. That usually translates in many tons of munitions and fuel.

Check this out. This page is from the Midway Roundtable it covers the Japanese Carriers hit by aircraft.

This is the page from the same site on some of the US carrier losses.

The US planes were dropping some pretty hefty ordinance. Some 500lb bombs but also several of the heavier and more potent 1,000lb class of bombs.

edited 9th Jun '18 5:03:48 PM by TuefelHundenIV

Akagi off the top of my head, while Kaga took multiple hits during midway, and wasn't evacuated until the next day after being dived by 27 aircraft.....

Akagi was dove at by 3 that realized they accidentally all attacked the same target, took 1 hit, and was a total loss in a couple hours due to the munitions cooking off.

But alright, I just wanted to double check due to the sheer bulk of torpedoes... sorry.

I edited in some links to a round table that shows some of the hits and explains the damage so you 'd me on that one.

As far as I can tell yeah they were similar to US carriers in that they carried enough munitions for a number of sorties.

The six fleet carriers of the Kidou Butai that hit Pearl Harbor had enough stores that they could fly at least three full sorties of torpedo and bomber aircraft. The third strike was loading and getting ready when Admiral Chuichi Nagumo called off further attacks.

They weren't even close to empty in terms of stores by then.