The PT Boat Forum
http://www.ptboatforum.com/cgi-bin/MB2/netboard.cgi

ť Forum Category: PT Boats of WWII
http://www.ptboatforum.com/cgi-bin/MB2/netboard.cgi?cid=101&fct=showf

ť Forum Name: PT Boats - General
http://www.ptboatforum.com/cgi-bin/MB2/netboard.cgi?fct=gotoforum&cid=101&fid=102

ť Topic: Original ELCO Records and Drawings
http://www.ptboatforum.com/cgi-bin/MB2/netboardr.cgi?cid=101&fid=102&tid=4127

Hi All

I have happy news to report. It seems that when General Dynamics transferred their ELCO records and drawings to Mystic Seaport back in 1988, Mystic was only interested in the yacht info (I was told that they gave the PT Boat records to the 'Navy). Well it turns out that Mystic actually gave these front office ELCO records to the Naval War College (NWC) in Newport, RI. This includes hundreds of original and official copies of drawing starting with the 70 footer thru the 80 footers (they even have PT-9 drawings although I only found fittings and equipment). The front office records are very extensive (including correspondence drafts) and if anyone is interested in the Thunderbolt, you will be in Heaven! Had no idea there were so many versions and they even installed these on several Battleships near the end of the war. We have a 3x20mm version, a 4x20mm version, 4x20mm with 2x.50cal and a 6x.50cal with 2x20mm, and I'm sure there were more, just got tired of looking...

If anyone would like to see the records or has questions of the archivists, you may contact them at nhc@usnwc.edu. Dara Baker is the Head Archivist. Since this is on a naval base, it will be a wee bit of a project to get there. Even for us retired military it's an effort since NWC itself has restricted access. Dara mentioned that maybe they could set up a special Elco PT Boat Archive event(s) specifically to support us researchers. This is still at the brain storming point, but might be something worthwhile. She did point out that the ELCO records had not been electronically catalogued and was still pretty much as it was shipped back in 1990. They will now become a priority and she will forward the info to me as it is done. There just had not been anybody interested before. I mentioned that there was a good chance that was about to change.

They do not have onsite capability to make copies of the drawings, but she will work with archivists to determine the best way to preserve these items (many are very fragile). I did take photos of a few drawings. I apologize for the attached photo quality, but some of these drawing are huge and others have a massive case of the wrinkles! In order we have three 80' Elco starting with Drawing No 3001, 3002 (Dec 41), and 3014 (my favorite - the pencil work is very nice). The blue print is the C4 version of the Thunderbolt (4x20mm) from 1943.

Cheers,
Andy

.

Posted By: Andy Small | Posted on: Jul 27, 2016 - 3:17pm
Total Posts: 261 | Joined: Nov 20, 2013 - 9:04pm

OUTSTANDING.....

Will

Posted By: Will Day | Posted on: Jul 27, 2016 - 3:59pm
Total Posts: 1955 | Joined: Oct 8, 2006 - 4:19pm

Thank you and nice work Andy, hopefully they will get them digitized someday before they turn to dust. And thanks for the Thunderbolt info too, I found it surprising that they waffled about the configuration so much.

Posted By: Jeff D | Posted on: Jul 29, 2016 - 10:43am
Total Posts: 2200 | Joined: Dec 21, 2006 - 1:30am

Jeff;
Not waffle, adaptations. This way it could be utilized on several different platforms.
Take care,
TED

Posted By: TED WALTHER | Posted on: Jul 29, 2016 - 4:51pm
Total Posts: 3059 | Joined: Oct 16, 2006 - 7:42am

All,

Here are some interesting Thunderbolt photos The first is an early version with 6x.50 cal and 2x20mm that was temporarily install on PT-156. I did not happen to come across any supporting test data, but it's probably there somewhere. The second is one of my favorites since it has Rat Rod written all over it. This is another early version of the Thunderbolt with 2x.50 cal and 4x20mm. A slight modified version of this was the Thunderbolt tested on PT-160 in December 1942. The last is a photo of the actual production Thunderbolt which is the 4x20mm version. This is the type installed on the four Ron 29 boats and the ones installed on the seven Battleships. This production photo was taken in May 45. Correspondence indicated that ELCO was in the process of securing a big order for these to be mounted on various ship classes.

There are some earlier forum postings and speculation about the weight of these mounts. These mounts were actually lighter than the old single 20mm Mk 4 mounts. Sea Trial data shows little structural impact and implies less stress than the 40mm mounts. No issues with boat performance. Ron 29 was very happy with them and assigned one boat to their 3 boat patrols. The amount of intense firepower was very effective for neutralizing German targets. ELCO also was able to take Ron 29 feedback and update the follow on systems. In my mind, these are the forerunner to the 20mm Vulcan gun mounts and probably would have played an important suicide stopping role during the planned invasion of Japan.

All the ELCO documents and drawings are currently professionally stored, so no worries about these wasting away while the War College prioritizes. The drawing that mostly have issues are the cloth versions with the special protective coating. The drawings are mostly rolled and the plastic edges on these particular types have sometimes fused together making it necessary to have someone professionally handle them in order to open them. The actual drawings in these are in great shape, although some look like the were actively referenced on the factory floor during boat production (very nice patina).

Cheers,
Andy

Posted By: Andy Small | Posted on: Jul 29, 2016 - 7:58pm
Total Posts: 261 | Joined: Nov 20, 2013 - 9:04pm

Interesting stuff, Andy. Thanks!

Will

Posted By: Will Day | Posted on: Jul 30, 2016 - 10:58pm
Total Posts: 1955 | Joined: Oct 8, 2006 - 4:19pm

I'm not sure how relate-able this may be, however, the Norfolk And Western (railway) Historical Society was able to save [long story] a vast amount of original steam locomotive drawings a number of years ago. They have done an amazing job of sorting and cataloging the information.

Most of the drawing were drawn on linen rather than as "blueprint". They also have been able to acquire a couple of machines that smooth out the drawings. These amount to what is very basically a large roller type of ironing machine.

Hopefully something similar can be accomplished with the PT boat drawings.

Posted By: Big Jim | Posted on: Aug 4, 2016 - 4:22am
Total Posts: 10 | Joined: Mar 1, 2016 - 4:53pm

What a great find! Just when you thought it had all been discovered too! I'm glad to hear they're interested in preserving it too.
Dave

David Waples

Posted By: David Waples | Posted on: Aug 9, 2016 - 7:07pm
Total Posts: 1679 | Joined: Jan 2, 2007 - 9:55pm

Another visit to the NWC today and have more info to share. As for the drawings I went through 24 boxes of drawings, which is probably about 1/20th of what they have. I did see the original ELCO Plane drawing 3107 (including a little cartoon face along the edge) as well as the original fuel appendage drawings 3095/96/97. I had not previously observed that the ELCO Plane employed a small bow fin. For the profiles, I've only been able to find the original PT103 and copies of the PT139 (3014) and Profile drawing 3033 which has the Mk13 torpedoes with 20mm fore and aft. They also have the original drawing of a proposed bridge windshield (3256) dated Oct 42. Several early original drawings from Dec 41. Several detailed construction drawing including the bridge and things such as the forward 37mm and 20mm gun mount pad (did not know these were two layers of mahogany topped with plywood) as well as the aft 40mm steel mount. My best guess is that about 1/2 are originals (mostly later ALTs) and I'm happy to update my previous report, that most are in excellent condition.

Another interesting find was a proposal for an 80' PTC and PTG which would have had various configurations with a forward 40mm and Thunderbolt Aft. Date of proposal was Feb 43 and the PTG proposals were using the Bullfrog (tested on PT 196) to launch MK13s (one proposal had 6 torpedoes!). The proposals are supposedly ELCO drawings 1088 and 1099, but those numbers correspond to 77' drawing numbers, so who knows if they still exist. Be interesting to see these very heavily armed boat profiles.

Found a copy of the Dewandre Turret Operating Manual and lots of info on smoke dispensers including the airborne versions mounted and tested in late 1945 on F6Fs and P-47s for covering amphibious landings (P-47 worked better due to the mounts being farther from the prop wash). In July 45, the updated Mk15 thunderbolt (Mk 14s were on the Ron 29 boats) was being evaluated against other mounts such as the twin 20mm and the quad .50cal for anti-suicide ship defense. It seems it was the difficulty in shooting targets due to the rough ride of the ELCO PTs that was a major contributing factor to these mounts not being further employed on ELCO PTs. Mount stress on the hull does not seem to have been an issue, although deck flex was a concern. Navy was looking at other more stable platforms such as LCIs and larger ships for these mounts.

Also looked through a great deal of info on the Russian ELCOs including tests of the Mk19 Mod 4 torpedo tubes (PT 731) in Oct 44 using Mk 15 torpedoes.

Will keep you posted.

Posted By: Andy Small | Posted on: Aug 12, 2016 - 8:02pm
Total Posts: 261 | Joined: Nov 20, 2013 - 9:04pm

Andy;
Wow! What a ELCO PT Treasure trove! Interested in all! I hope this will be available someday.
Take care,
TED

Posted By: TED WALTHER | Posted on: Aug 13, 2016 - 5:07am
Total Posts: 3059 | Joined: Oct 16, 2006 - 7:42am

It is a treasure, and nice to finally have a honey pot near where I live.

Another interesting rabbit hole. PT 731's Oct 1944 Mark 19 Mod 4 torpedo tube firing of the Mark 15 torpedo got me wondering. Doing a quick internet search, the Mod 4 was for the longer 21 25' torpedoes which corresponds to the Soviet 53-39 torpedo (295.3 long, weight 3,924 lbs, warhead 698 lbs) which had a top speed of 51 knots. Pretty vicious big torpedo. For a comparison, the Mark VIII was 256.3 long, 2600 lbs, warhead 466 lbs and speed 36 knots. Explains why they only had two tubes. Quite a sting!

- Andy

Posted By: Andy Small | Posted on: Aug 13, 2016 - 5:30am
Total Posts: 261 | Joined: Nov 20, 2013 - 9:04pm

Just found this... wow just wow!

I'd like to point out that it's preferable of course, but not necessary to scan such engineering drawings... good images can be obtained with a cell phone camera!

I was researching a line of old marine engines earlier this year, the Hicks engine famous for powering much of San Francisco's small fishing boats in the 1920's. Old blueprint work shop copies are all that's left of the the hundreds of drawings, and the SF Maritime museum needed $20 each to have them scanned. No way I was going to pop for that.

But could I just come in and take snap shots? Why sure! So I spent a day there and filled up my memory card with carefully shot images of the prints... an example below.

Note that with the dimensions on an engineering drawing, the part doesn't need to be scaled off the paper... the dimensions are right there! So the image can be cockeyed and stained, no matter.

Typical blueprint (stamped 1927):

[image]http://static.rcgroups.net/forums/attachments/4/9/6/5/9/a8698057-250-20160204_134211a.jpg[/image]

My CAD model created from such prints:

[image]http://static.rcgroups.net/forums/attachments/4/9/6/5/9/a8716378-19-asy217.JPG[/image]

Patrick Matthews
Matthews Model Marine
http://matthewsmodelmarine.wordpress.com/

Posted By: Patrick Matthews | Posted on: Aug 24, 2016 - 6:04pm
Total Posts: | Joined: Unregistered