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» Forum Category: PT Boats of WWII
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» Forum Name: PT Boats - General
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» Topic:
torpedo tubes
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First of all I like to thank all of you helping me to solve the mystery of
the function of louvres, part of the Elcoplane System.
Now to my otherr questions:
As you all know that the torpedo tubes of the early Elco and Higgins are of different design. Can someone explain, in layman's language, the
two different systems, and why not the navy used one system to
simplyfy manufacturing and maintenance. Is one system better than the other?
Victor
Victor K Chun
Posted By: victorkchun | Posted on: Jan 24, 2009 - 1:37pm
Total Posts: | Joined: Unregistered
If I am not mistaken, Higgins came up with their own design torpedo tubes using compressed air to propel the torpedoes. Other Companies, such as Elco and Huckins Yacht Corporation used the Black Powder charged Tubes. In the cae of Elco and Huckins, they simply used what was available at the time, while Higigins experimented with the compressed air tubes. I am not sure if Elco did any testing on the air driven tubes, although I sem to remember a photo or two somwhere showing the boats with that type system. Of course, the roll of racks pretty much changed things for all the boats.
Posted By: Frank J Andruss Sr | Posted on: Jan 24, 2009 - 1:53pm
Total Posts: 3497 | Joined: Oct 9, 2006 - 6:09am
I forgot to mention that the black powder charge was an impulse cartridge that was inserted into the firing mechanism, using a special 3 inch case roughly 13 inches long. I think the Higgins boats caried an air compresser to refill the air resevoirs. Jerry Gilmartin can shed more light on them then I can.
Posted By: Frank J Andruss Sr | Posted on: Jan 24, 2009 - 2:06pm
Total Posts: 3497 | Joined: Oct 9, 2006 - 6:09am
Frank
Those Elco boats that had the compressed air fired tubes were the boats exported to the Soviets. They perferred them because their boats operated in extreme cold and the compressed air tended to operate better in those conditions.
Garth
Posted By: TGConnelly | Posted on: Jan 25, 2009 - 7:56am
Total Posts: | Joined: Unregistered
Thanks Garth:
I often wonder why Elco did noit switch to the Air Compressed Tube to rid themselfs of the problems associated with the B.P charged tubes they had, unless the shortage of tubes was the problem. Often many of the boats had their tubes installed after.
Posted By: Frank J Andruss Sr | Posted on: Jan 25, 2009 - 9:59am
Total Posts: 3497 | Joined: Oct 9, 2006 - 6:09am
You notice the Elco tubes in "They Were Expendable" were air-setups...
Will
Posted By: Will Day | Posted on: Jan 25, 2009 - 2:42pm
Total Posts: 1955 | Joined: Oct 8, 2006 - 4:19pm
Hi Victor,
I love your excellent PT Boats reference book by the way. It is definitely one of the more authorative sources of information about US PT Boats that I have seen. We even used one of the drawings in it of the torpedo aiming device to create a mockup to mount on the PT658.
Anyway, on the subject of torpedo tubes, what I know of the Higgins design is that they were installed on numerous Higgins boats and changed designs to accomodate the Mark 13 torpedo also. The original tubes had the curved air "Impulse Chamber" and was designated the
"21 inch Mark 19 Mod 4" tube. I am certain that below decks in the engine room was a torpedo tube heater as well as an air compressor, I suppose they could recharge the impulse chamber after firing the torpedo using the air compressor. These had the curved air chamber mounted on top of the tube. The other tube designed for the later Mark 13 torpedo had two straight parallel air chambers mounted beside one another on the top and were shorter. I got a lot of this info from looking at photos posted under "Higgins Factory Photos" on Gene Kirklands excellent site "PT King" [url]http://www.geocities.com/pt_king/[/url]
as well as the Louisiana Digital Library Higgins Industries Collection
[url]http://louisdl.louislibraries.org/[/url]
There are several drawings such as "Torpedo tube extractor control lines, heater and air compressor arrangement " that show some of these details. I hope this helps. Jerry
Jerry Gilmartin
Posted By: Jerry Gilmartin | Posted on: Jan 25, 2009 - 3:50pm
Total Posts: 1473 | Joined: Oct 8, 2006 - 11:16pm
Frank, the Osprey book mentions that the ELCO 21" x 20' 8" Mk 18 Mod 1 tube was provided by ELCO but subcontracted out. This caused delays and some boats were turned over to the Navy for shakedown without the tubes installed. They were later returned and the tubes installed. Larger 22.5" tubes were developed but only installed on about 20 boats before the rollover racks were made standard.
Google books has an excerpt:
[url]http://books.google.com/books?id=X1AvTqSg2QsC&printsec=frontcover[/url]
Posted By: Jeff D | Posted on: Jan 26, 2009 - 12:23am
Total Posts: 2200 | Joined: Dec 21, 2006 - 1:30am
Frank,
I cannot answer that for you, as I do not know.
Garth
Posted By: TGConnelly | Posted on: Jan 26, 2009 - 6:24am
Total Posts: | Joined: Unregistered
>...the Osprey book mentions that the ELCO 21" x 20' 8" Mk 18 Mod 1 tube was provided by ELCO but subcontracted out. ..<
You might want to confirm this with other sources. This particular book is the most error-filled book on PTs I have ever read.
Al Ross
Posted By: alross2 | Posted on: Jan 26, 2009 - 7:14am
Total Posts: 993 | Joined: Oct 30, 2006 - 8:19pm
You should know Al, I'll take the books information with a grain of salt and thanks.
Posted By: Jeff D | Posted on: Jan 26, 2009 - 12:26pm
Total Posts: 2200 | Joined: Dec 21, 2006 - 1:30am