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 Author  Topic: Bow Launched Torpedo Question
  Andy Small

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Post a Reply To This Topic    Reply With Quotes     Edit Message     View Profile of Andy Small  Posted on: Apr 15, 2016 - 6:11pm
I've been trying to figure out how the old coal/oil powered torpedo boats fired and managed to avoid running over their single bow launched torpedoes during an attack. This would also apply to a few later gas powered torpedo boats that also had a single bow torpedo. All the boats I've seen with a bow tube show the tubes angled down, and I assume compressed air was the launching force, but that takes me back to the "how did they avoid running over their own torpedo?", especially since we're talking of potential speeds of 25-30 knots or more.

Thanks!

Andy


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Andy Small

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Post a Reply To This Topic    Reply With Quotes     Edit Message     View Profile of Andy Small  Posted on: Jul 1, 2016 - 8:12am
In an 1916 issue of MotorBoat magazine I found my answer concerning bow launched torpedoes. In Feb 1915 when Navy representatives were putting Hickman's privately funded 4 engine sea sled motor torpedo boat through its tests, test #3 series were simulated torpedo attacks where the sea sled clipped along at 1400 rpm (full speed of approximately 35 knots - not bad for a 10 ton vessel with only 740hp) and then throttled down (average time during series was 4 seconds) to torpedo firing speed of about 8.5-10 knots.

I find it interesting that having companies privately fund torpedo boat projects is a full blown US Naval Tradition starting all the way back to 1885 with the Herreshoff Stiletto.


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Will Day

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Post a Reply To This Topic    Reply With Quotes     Edit Message     View Profile of Will Day   Send Email To Will Day Posted on: Jul 1, 2016 - 9:37am
Interesting...

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ROSS FISHER

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Post a Reply To This Topic    Reply With Quotes     Edit Message     View Profile of ROSS FISHER  Posted on: Jul 1, 2016 - 5:25pm
This puts me in mind of the Q-boats of the Philippine Off-Shore Patrol with their stern-launched, forward -running 18-in torpedos. Talk about a tricky process...
Basically a WWI British Thornycroft design, they managed 39 knots on three 600-hp gasoline engines. They were promised 55 boats by 1946 and had three on hand on December 7, 1941. Brave to the last, they fought alongside John Bulkeley's Ron 3 right to the end.

Ross Fisher

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  TED WALTHER

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Post a Reply To This Topic    Reply With Quotes     Edit Message     View Profile of TED WALTHER   Send Email To TED WALTHER Posted on: Jul 1, 2016 - 8:09pm
Andy;
Here is a link about the boats Ross is talking about. The photos were taken in November 1941 and were in Life magazine.

https://bataancampaign.wordpress.com/2014/02/22/they-were-expendable-too-the-torpedo-boats-of-the-off-shore-patrol/

Take carer,
TED


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Andy Small

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Post a Reply To This Topic    Reply With Quotes     Edit Message     View Profile of Andy Small  Posted on: Jul 1, 2016 - 8:50pm
Thanks! I've also enjoyed the article Q-Boats:Heroes of the Off-Shore Patrol, The Untold Saga of Philippine Army's PT Boats by Commodore Ramon Alcaraz, Philippine Navy (Ret.).

I've collected several post WW1 articles on the CMBs by Thornycroft. When they were doing the initial designs in the Summer of1915 after sending an Admiralty rep (Lieutenant G.C.E. Hampden) to see the Hickman's Sea Sled trials up in Boston, they first had the torpedo firing astern since this was the simplest arrangement. This meant turning away from the attack before launching the torp and was considered an unreliable tactic. In late 1915, dropping the torpedo fin first over the stern was tested with a somewhat slow boat. Results showed that if boats had a speed over 30 knots, this would work and by April 1916 the first three CMB's where complete. I think it also interesting that communist post WW2 torpedo boats continued to use this same method of launching fin first:

Andy


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Andy Small

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Post a Reply To This Topic    Reply With Quotes     Edit Message     View Profile of Andy Small  Posted on: Jul 2, 2016 - 3:44am
Here's a video showing a two man Italian MTSM launching a stern launch torpedo:

Stern Launch Torpedo

The video shows the loading of the torpedo and launch from the boat and from a chase boat. Also interesting is the stern image showing not only the tube, but two stored 95hp Alfa Romeo outboard motors that would fold down once in the water. Pretty cool innovative stuff since the MSTM units transported these small boats by trailer to where they were needed.

Not sure if these units ever went up against UK or US PTs during the war.


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