Topic: What is it? (diagonal pipe, rail, structure on hull) (Read 7521 times)

big_bri · « **on:** April 02, 2016, 01:29:03 pm »

I wonder if any of you very knowledgeable people could help me?
I`m building an armed trawler and when looking at various photos, I noticed that some of the trawlers had twin rails running up/down the hull amidships.

I wonder if anyone could shed any light as to what these were used for, I`ve had suggestions of raising/lowering of asdic, and for streaming paravanes.
Any help would be most appreciated.

imsinking · « **Reply #1 on:** April 02, 2016, 01:49:50 pm »

De-gaussing coils perhaps ?, to foil magnetic mines.
Bill

Sandy · « **Reply #2 on:** April 02, 2016, 02:04:10 pm »

Hi Brian,

I still think, because of the location, it is something to do with the Asdic dome, possibly for raising it and lowering it.

I checked out where I had read about removing the dome before entering harbour and it is in the book 'Darkest before Dawn' when HMT Northern Wave returns to Londonderry with the survivors from Empire Heritage and the rescue ship Pinto and has to stop at Moville to remove her asdic dome before proceeding up river.

Flicking through Lenton and Colledge's book it seems to me that they are only on A/S trawlers and not M/S trawlers.

Ironically the Northern trawlers don't have those rails which may tie in with the fact that Wave had to have hers removed rather than raised.

Just my 2p.

All the best
Sandy

big_bri · « **Reply #3 on:** April 02, 2016, 02:16:07 pm »

After doing some research, I know type 122,123 and 145 asdic was installed in some trawlers. These were portable asdic sets.
Most trawlers had hydrophones fitted to the inside of the hull, both port and starboard just aft of the bow.
I still cant find any concrete information on how these sets were installed!

big_bri · « **Reply #4 on:** April 02, 2016, 02:32:27 pm »

Reading a bit more into the detachable sets.... these seem to have been fitted internally with the transducer attached to the inside of the hull as with the hydrophones, highly inefficient and the next improvements were asdic domes.

John R Haynes · « **Reply #5 on:** April 03, 2016, 03:20:33 pm »

I have a plan of the Armed Trawler Lady Shirley by David Macgregor that shows this feature and describes this as " Asdic Dome inhaul/hoist wire " which I guess is a sort of slide that carries a wire, port and starboard to the bottom of the ship some 20 degrees ahead.
Incidentley I am , when time allows ,asked to make the Armed trawler Kingston Topaz . I have searched for pictures but only have one of KingstonTurquoise.
I need plans and detail, a photo ? any help out there ?
John

big_bri · « **Reply #6 on:** April 03, 2016, 08:10:34 pm »

Many thanks to all, especially Sandy and John for the info, my curiosity is now abated

I`m afraid I can`t help with Kingston Topaz John, sorry.

DavieTait · « **Reply #7 on:** April 03, 2016, 08:19:14 pm »

http://trawlerphotos.co.uk/gallery/showphoto.php?photo=133649
http://uboat.net/allies/warships/ship/13530.html

She was built by Cook, Welton & Gemmill (Beverley, U.K.) and I believe the Hull Museum holds the plans from that yard John

tonyH · « **Reply #8 on:** January 19, 2018, 10:25:37 am »

Mornin' All,

Regarding the diagonal pipe, rail, structure on the hull.

This is on the port side of a USN converted Flower. It appears on lots of them but not all. The vast majority of the photos on Navsource etc are from the port side so I've not confirmed whether it appears on both sides. It's probably obvious but I'm not in thinking mode.

Any ideas?

derekwarner · « **Reply #9 on:** January 19, 2018, 10:51:02 am »

Tony......you will find these angular [facing aft] external pipes below the main deck on British and American Naval vessels up till say the 1980's

They were as you suspect, to take bathroom wastes and waters overboard

Still a great progress on HMS Victory when the Heads were at the bow...

Derek

TailUK · « **Reply #10 on:** January 19, 2018, 11:27:19 am »

I don't think it's a waste pipe. It's angled forward towards the bow which could result in back pressure in heavy seas. I should imagine that the results could be very unpleasant.
It's possible that it's degaussing cables or something like that

tonyH · « **Reply #11 on:** January 19, 2018, 11:38:19 am »

Thanks Derek and now you've said it, it does look like the downpipe on the side of a house! It also seems logical that the angle of the main pipe would allow the bottom section to be flushed out when going ahead.
That said, any excess of pressure...................................

derekwarner · « **Reply #12 on:** January 19, 2018, 11:54:09 am »

De-gaussing cables were laid & secured on deck level...and around the full perimeter of the vessel.....thus to create a discharge of electrons or reduce the magnetic signature of the vessel

The circuit of a de-gaussing cable run were never intermixed or piped in waste water overboard pipes

The value in the weight of copper cabling in vessels de-gaussing systems was such that the Admilitary had this removed prior to an vessel being scrapped or sent to the breakers

Derek

TailUK · « **Reply #13 on:** January 19, 2018, 12:01:14 pm »

Having consulted with the John Lambert drawings he shows it as "Asdic Dome, Inhaul wire-stowed position".

As Derek said not a degaussing cable but not a waste pipe either.

gingyer · « **Reply #14 on:** January 19, 2018, 12:51:00 pm »

this was fitted to many armed trawlers too

it was used for sonar, there was small hand winches inside the bulwark that lifted and lowered the sonar head...

EDIT: I knew this had been discussed before..
topic,54423.msg563068.html

tonyH · « **Reply #15 on:** January 19, 2018, 08:00:18 pm »

Right Chaps,

I've done some more research on the types of Asdic/Sonar (depending whether I was reading British or American stuff) and there is only 1 setup which could pertain, except where the dome had 'just in case' preventer lines.
This is for the modification when the basic Type 123/4 was augmented by the addition of the Type 147 which was sword shaped and could be levered up or down for deep-diving targets.
It could be moved by lines or from inside the vessel.
I've also checked the photos of all the US Flowers and the only ones that have the strange pipework are the ones that were Canada built and then remodified by the USN. It's s**s law that it's that type I'm reworking for Warwick

None of the 'normal' Canadian ones have the fittings.

I just think that what now appear to be rope or chain ducts are so overworked and the 'brackets' seem so large that I'll keep looking.

Cheers for now

derekwarner · « **Reply #16 on:** January 19, 2018, 10:43:08 pm »

Goodness I do stand corrected

...the example pipe as attached to a hull certainly was not a waste water pipe ... which were also attached to Warship hulls

...anyway....Asdic/Sonar ...it's all Under Water stuff.....not for the feint hearted Above Water people

I am sure gingyer is correct that these Asdic/Sonar components were previously discussed

Akira · « **Reply #17 on:** January 20, 2018, 01:23:27 am »

A quick review of photos of Canadian Flowers x-ferred to the US during the war does not show a consistent mounting of this pipe. Further, images taken later in the war, 1944ish, pretty much show the fitting removed. Updated Sonar? Lastly, there are several photos that appear to show this fitting stopping well short of the waterline and at the same time quite well braced upon the hull. Inquisitive minds want to know....

John R Haynes · « **Reply #18 on:** January 20, 2018, 01:03:12 pm »

These were part of the primitive asdic arrangement and were visible port and starboard , to run a cable under the hull where the director was carried

Akira · « **Reply #19 on:** January 20, 2018, 01:16:15 pm »

Thank You John!

Netleyned · « **Reply #20 on:** January 20, 2018, 03:05:05 pm »

Not so primitive when used on the Tupperware Mine hunters

We had a dome cover to go under the hull.
Ask Jerry C
Think he was one of our RNR Mining Officers.

Ned

tonyH · « **Reply #21 on:** January 21, 2018, 04:05:51 pm »

Many thanks indeed John!

Do you know whether they were power cables or just lines to enable the units to be lifted for maintenance/repair etc?
There's a decent article on http://jproc.ca/sari/asd_gen.html which gives a description of the lengths they had to go to to replace bits etc. so if they were the latter they must have been trying a more 'professional' system which must have been abandoned at some later stage?

Cheers

Tony

John R Haynes · « **Reply #22 on:** January 21, 2018, 05:11:30 pm »

On David MacGregor plans of the A/S trawler Lady Shirley he shows the asdic dome inhaul wire running at a forward angle from the bulwark top to run under the hull. So I assume this enabled the dome to be pulled out at some point , maybe for servicing. The cable runs from the bulwark through fairleads situated and on the bulwark rail and then again presumably to a deck fixing .

tonyH · « **Reply #23 on:** January 21, 2018, 07:09:23 pm »

Yes, it's certainly the most logical option and the drawing and photo that Les (TailUK) put on earlier in the thread follow the same line in that the rig could be carried up to deck level as or if required.
It's just that a quick measurement of the fitting from the photo gives what appears to be a pipe that could easily be as much as 9" diameter, or even more, with fittings of similar bulk.
There is a line that appears to be running from the lower end into the water, so could it just be happenstance that there is a second application and that the line runs behind the fitting, rather than through it.
For example, sonobuoys and dipping sonar were being developed by us just at that time. They were trialed in 1942 as anti-mine sonar under the code name High Tea (At least according to Wiki

)
A drop pipe would be feasible, since they would enter the water at the point where the rolling of the ship would have least effect?

Anyhow, whatever the reason, they're going to have to be incorporated in the model!!!!

Cheers

Tony

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Author Topic: What is it? (diagonal pipe, rail, structure on hull) (Read 7521 times)