# PT boats **URL:** \ **Category:** Factual Questions\ **Created:** [May 4, 2000, 11:50pm UTC](https://boards.straightdope.com/t/pt-boats/18617 "2000-05-04T23:50:56Z")\ **Posts on this page:** 15\ **Page:** 3
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [August 31, 2023, 11:33pm UTC](https://boards.straightdope.com/t/pt-boats/18617/41 "2023-08-31T23:33:26Z")
> [@What\_Exit](#): > > I’m having trouble recalling a BB that went down to a single mine or Torp. > I’m almost certain no single mine sank a Battleship. HMS _King Edward VII_, **HMS Irresistible, HMS Ocean, and Bouvet** all sank with one mine reported-. To be fair, they were all Pre dreadnought battleships. [List of sunken battleships - Wikipedia](https://en.wikipedia.org/wiki/List_of_sunken_battleships#:~:text=A%20decade%20later%2C%20the%20Marine,Kong%C5%8D%20with%20over%201200%20casualties). I thought the HMS Royal Oak was sunk with one torp, but it took maybe 3. However, wiki says the HMS _Triumph_ was sunk by one torp, along with the HMS _Majestic_. So was the French battleship _Suffren_, and the French battleship _Gaulois_. It took two to sink the HMS _Cornwallis_, same with the SMS _Szent István_, which was sunk by two Italian Torpedo boats. The Japanese battleship _Asahi_ took two torps, and so did the Japanese battleship _Kongō_, The SMS _Kurfürst Friedrich Wilhelm_, renamed the _ **Barbaros Hayreddin** _ was sunk by one British torp. ---
**Author:** ![What\_Exit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/what_exit/32/10652_2.png) [@What\_Exit](https://boards.straightdope.com/u/What_Exit)\ **Post date:** [August 31, 2023, 11:46pm UTC](https://boards.straightdope.com/t/pt-boats/18617/42 "2023-08-31T23:46:24Z")
Fair enough, I’m wrong again. ---
**Author:** ![Capn\_Carl](https://avatars.discourse-cdn.com/v4/letter/c/838e76/32.png) [@Capn\_Carl](https://boards.straightdope.com/u/Capn_Carl)\ **Post date:** [September 1, 2023, 12:09am UTC](https://boards.straightdope.com/t/pt-boats/18617/43 "2023-09-01T00:09:45Z")
You would probably be correct if you excluded pre-dread battleships. ---
**Author:** ![Capn\_Carl](https://avatars.discourse-cdn.com/v4/letter/c/838e76/32.png) [@Capn\_Carl](https://boards.straightdope.com/u/Capn_Carl)\ **Post date:** [September 1, 2023, 12:27am UTC](https://boards.straightdope.com/t/pt-boats/18617/44 "2023-09-01T00:27:36Z")
_HMS Marlborough_ was in rough shape after Jutland, where she was hit by 1 torpedo. ---
**Author:** ![Dissonance](https://avatars.discourse-cdn.com/v4/letter/d/85f322/32.png) [@Dissonance](https://boards.straightdope.com/u/Dissonance)\ **Post date:** [September 1, 2023, 2:58am UTC](https://boards.straightdope.com/t/pt-boats/18617/45 "2023-09-01T02:58:51Z")
> [@Capn\_Carl](#): > > Failing to mention that _Kaga_ (or _Bismarck_, or _Hornet_, for that matter) was scuttled isn’t much of an oversight. She was probably sinking and was certainly a constructive loss. The _Manchester_ case is a bit different. A single smallish torpedo doesn’t sufficiently explain the loss of a 9500 ton cruiser. Additionally, and much more pertinent to the issue, is that the single smallish torpedo absolutely wasn’t the cause of the loss of _Manchester_. The commander issued the orders to scuttle because he feared repairs would not be affected before _Manchester_ was in danger of further attacks, not because she was in any danger from the sinking from the single torpedo hit. The commander issued orders to scuttle at 0250, and the initiation of the scuttling charges couldn’t be stopped when he was informed 5 minutes later that power had been restored to one turbine and steering - and had actually been restore at 0202, 45 minutes _before_ he gave the order to scuttle, so she wasn’t ever actually in danger of further attacks. ---
**Author:** ![Capn\_Carl](https://avatars.discourse-cdn.com/v4/letter/c/838e76/32.png) [@Capn\_Carl](https://boards.straightdope.com/u/Capn_Carl)\ **Post date:** [September 1, 2023, 7:57pm UTC](https://boards.straightdope.com/t/pt-boats/18617/46 "2023-09-01T19:57:08Z")
Oh, I agree. The ship was damaged, not sunk, by the torpedo. She was lost thru poor damage control. ---
**Author:** ![Dissonance](https://avatars.discourse-cdn.com/v4/letter/d/85f322/32.png) [@Dissonance](https://boards.straightdope.com/u/Dissonance)\ **Post date:** [September 1, 2023, 9:00pm UTC](https://boards.straightdope.com/t/pt-boats/18617/47 "2023-09-01T21:00:13Z")
Yeah, looking back I probably worded that weirdly and in a way that could make it sound like I was in some disagreement with what you wrote, I only meant to emphasize what you said. If I had it to do over again, I’d drop the “and much more pertinent to the issue, is that” from the first sentence. Apologies. ---
**Author:** ![Capn\_Carl](https://avatars.discourse-cdn.com/v4/letter/c/838e76/32.png) [@Capn\_Carl](https://boards.straightdope.com/u/Capn_Carl)\ **Post date:** [September 1, 2023, 9:05pm UTC](https://boards.straightdope.com/t/pt-boats/18617/48 "2023-09-01T21:05:21Z")
No offense was meant or taken. ---
**Author:** ![Mk\_VII](https://avatars.discourse-cdn.com/v4/letter/m/5f9b8f/32.png) [@Mk\_VII](https://boards.straightdope.com/u/Mk_VII)\ **Post date:** [September 2, 2023, 12:10pm UTC](https://boards.straightdope.com/t/pt-boats/18617/49 "2023-09-02T12:10:43Z")
Centerline bulkheads did for a lot of those older pre-dreadnoughts, also that torpedo warheads had become much bigger than the earlier ship designers had made provision for. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [September 2, 2023, 1:51pm UTC](https://boards.straightdope.com/t/pt-boats/18617/50 "2023-09-02T13:51:00Z")
> [@Mk\_VII](#): > > Centerline bulkheads did for a lot of those older pre-dreadnoughts I’m not disputing you, but can you expand on what you mean by this? What was different about the different eras’ ship designs and how did that increase vulnerability? ---
**Author:** ![Mk\_VII](https://avatars.discourse-cdn.com/v4/letter/m/5f9b8f/32.png) [@Mk\_VII](https://boards.straightdope.com/u/Mk_VII)\ **Post date:** [September 2, 2023, 10:31pm UTC](https://boards.straightdope.com/t/pt-boats/18617/51 "2023-09-02T22:31:27Z")
They thought a centreline bulkhead down the middle of the machinery spaces of the ship would limit flooding to one side of a compartment, but torpedo warheads had grown bigger and the explosive in them more powerful, the resulting weight of water, all on one side, affected stability until the ship capsized. This danger had been foreseen by naval architect Sir Edward Reade as long ago as 1871. _Irresistible_, which sank slowly, with only a small list, had the centreline bulkhead damaged causing free flooding across the whole compartment. ---
**Author:** ![Mk\_VII](https://avatars.discourse-cdn.com/v4/letter/m/5f9b8f/32.png) [@Mk\_VII](https://boards.straightdope.com/u/Mk_VII)\ **Post date:** [September 2, 2023, 10:39pm UTC](https://boards.straightdope.com/t/pt-boats/18617/52 "2023-09-02T22:39:04Z")
_Marlborough_ was hit at 1854hrs by a torpedo from _Wiesbaden_; initially she was able to maintain her place in the battle line, and the powerful pumps reduced flooding to manageable levels. About 0100 the following night it suddenly increased, perhaps due to worsening weather, after the Admiral transferred his flag she made for the Humber at 14kts and arrived there under her own steam, 37hrs after being hit. The damage was much worse than prewar tests, on the old _Hood_, had suggested. ---
**Author:** ![Capn\_Carl](https://avatars.discourse-cdn.com/v4/letter/c/838e76/32.png) [@Capn\_Carl](https://boards.straightdope.com/u/Capn_Carl)\ **Post date:** [September 4, 2023, 12:57am UTC](https://boards.straightdope.com/t/pt-boats/18617/53 "2023-09-04T00:57:37Z")
It’s surprising how much improvement there was in flooding control. A 10,000-15,000 ton pre-dread might sink after being hit by one torpedo with a ~400 pound warhead. A 25,000 ton WW1 batttleship might handle 2 torpedo hits with 600-800 pound warheads. By the 1930’s there were 10,000 ton cruisers that could do the same. The cruiser _Minneapolis_ survived 2 hits with 1100 pound warheads. ---
**Author:** ![TokyoBayer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tokyobayer/32/13989_2.png) [@TokyoBayer](https://boards.straightdope.com/u/TokyoBayer)\ **Post date:** [September 6, 2023, 3:42am UTC](https://boards.straightdope.com/t/pt-boats/18617/54 "2023-09-06T03:42:42Z")
> [@LSLGuy](#): > > The USN torpedos of the day were shite. Had they been better the PTs might have been more effective against larger IJN warships. It’s true that the USN torpedoes were shite, but there were other problems as well. How much more success would there have been only changing the torpedoes but not fixing the other issues is the premise for a good debate. First, while the issues with the Mark 14 torpedo is well known, early PT boats were outfitted with the older Mark 8 torpedoes which had their own set of issues, including their smaller warhead of less than 500 lbs. Another problem was with the black powder charge for launching the torpedoes from the launchers, where the humidity of the South Pacific caused frequent misfires. Sometimes flashes from the charge or burning oil in the tubes would give away the PT boat position to the enemy. Dry runs and other malfunctions also occurred. In 1943, the Mark 8 were started to be replaced by the Mark 13, designed as aerial torps. They weren’t ideal for PTs but their lighter weight while having a larger warhead, combined with the ability to be dropped from launching racks rather than requiring torpedo tubes saved more than 1,400 lbs each. For the question of given better torpedoes, how much more effective would they have been? Obviously, they would have had some more successes. There were a number of attacks, especially on destroyers, which possible torpedo failures may have contributed to unsuccessful results. Other attacks were broken up when the enemy discovered their position from the flashes. However, there were other issues which may have been more significant. One of the obvious flaws was the lack of radar for many boats. In the sea battles around Guadalcanal, the USN lacked the resources to maintain a constant presence in the immediate vicinity at night. The US ruled the seas during the day because of the air superiority, but lacked the number of ships to control the nights. PT boats were brought in to help with the coverage. This could have been the perfect opportunity to have made an even more significant contribution to the war. The appropriately nicknamed Iron Bottom Sound could only be approached from narrow channels to the east and around Savo Island to the west. The reinforcements to the IJA and supplies were delivered to a limited geographical area not far from the PT base. The lack of radar, bad coordination, inferior radios, inadequate training and insufficient numbers all contributed to limiting the results from the PTs. The PT program just wasn’t advanced enough to take advantage of the perfect opportunity. In a classical would’ves, could’ves, should’ves, had there been two squadrons of better trained, fully radar equipped boats, more of the shellings of Henderson Field and the reinforcements and supplies would have been prevented. ---
**Author:** ![Capn\_Carl](https://avatars.discourse-cdn.com/v4/letter/c/838e76/32.png) [@Capn\_Carl](https://boards.straightdope.com/u/Capn_Carl)\ **Post date:** [September 9, 2023, 11:34am UTC](https://boards.straightdope.com/t/pt-boats/18617/55 "2023-09-09T11:34:25Z")
Excellent post. Thanks for the info. [Previous page](https://boards.straightdope.com/t/pt-boats/18617.md?page=2)