Diesel Headcode Disc Positions...

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John Donnelly
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Diesel Headcode Disc Positions...

Postby John Donnelly » Tue Dec 03, 2013 10:11 pm

I wonder if anyone can tell me if there is a standard for diesel headcode disk positions when double heading or at the rear of a single engine.

Using the picture (photo by Bill Jamieson used with permission) below as an example:

Image

Clearly the headcode on the front denotes the type of the train but how would the discs be arranged at the rear of the leading locomotive and how would they be arranged at both ends of the second loco?

John

John Duffy

Re: Diesel Headcode Disc Positions...

Postby John Duffy » Wed Dec 04, 2013 10:46 am

The rear loco would be ignored and carry whatever head code it last displayed. Same with the rear of a single engine.

John

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John Donnelly
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Re: Diesel Headcode Disc Positions...

Postby John Donnelly » Wed Dec 04, 2013 11:16 am

Thanks for that, it confirms my suspicions.

John

Pannier Tank
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Re: Diesel Headcode Disc Positions...

Postby Pannier Tank » Wed Dec 04, 2013 7:09 pm

I seem to recall that the trailing loco (and the rear of the leading loco) would have the disc's closed to obscure the lamps i.e show full yellow end.
Regards

David

Natalie Graham

Re: Diesel Headcode Disc Positions...

Postby Natalie Graham » Wed Dec 04, 2013 7:15 pm

Pannier Tank wrote:I seem to recall that the trailing loco (and the rear of the leading loco) would have the disc's closed to obscure the lamps i.e show full yellow end.

I'll bet they very often didn't bother.

John Duffy

Re: Diesel Headcode Disc Positions...

Postby John Duffy » Wed Dec 04, 2013 8:29 pm

I don't think I ever saw a loco with all yellow discs. Unless us kids had been messing about with it!

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John Donnelly
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Re: Diesel Headcode Disc Positions...

Postby John Donnelly » Wed Feb 08, 2017 8:27 pm

I've got a further query on headcode discs. The photo at the top of the thread that I posted shows a Tyne Dock - Consett iron ore train in 1971. The photo below (copyright Bill Watson) shows the same train but in 1966/7:

Image

The headcode on the earlier train is different. As I understand it, the 66/67 train is displaying a code for a Class 4 train whereas the 71 train has a Class 5 headcode.

Excuse my ignorance but why the difference? Ignoring the bankers on the 66/67 train, the only difference I can see is that the 71 train doesn't have a brake van, would that be enough to explain the headcode difference?

John
Last edited by John Donnelly on Wed Feb 08, 2017 10:00 pm, edited 1 time in total.

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grovenor-2685
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Re: Diesel Headcode Disc Positions...

Postby grovenor-2685 » Wed Feb 08, 2017 9:49 pm

Pannier Tank wrote:I seem to recall that the trailing loco (and the rear of the leading loco) would have the disc's closed to obscure the lamps i.e show full yellow end.

I don't know of any such rule, nor would there be any logic to it, both the headcodes and the yellow ends are only required on the front of the train.
However the requirement for the rear of every loco when pulling a train was that threr should not be any red lamps.
Regards

PS. I would expect those trains to be class 4,
Express partly fitted, with the automatic brake operative on not less than 90% of the vehicles
A class 5 would be
Express train pipe fitted throughout with the automatic brake operative on not less than half of the vehicles
But it probably made very little difference given everybody on the route would know what those trains were anyway.
I don't think brake vans made any difference but the train showing class 5 may have had some wagons with duff brakes so failed the 90% rule.
Regards
Keith
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John Donnelly
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Re: Diesel Headcode Disc Positions...

Postby John Donnelly » Wed Feb 08, 2017 10:01 pm

Thanks Keith.

I plan on doing a 66/67 and a 71 version of the train so at least I've got the perfect excuse to use two different head codes...

John

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Noel
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Re: Diesel Headcode Disc Positions...

Postby Noel » Thu Feb 09, 2017 11:32 am

The earlier train is class 4 as Keith states, with at least 90% of the vehicles with VB, but the codes changed in 1969 it appears http://www.2d53.co.uk/Headcode/headcodeC.htm (or 1968 according to another source), and the later train is actually a class 6, fully fitted company or block train, etc. Presumably the change is down to the disappearance of non-fitted stock and the change to air brakes and different methods of calculating brake force?
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Noel

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grovenor-2685
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Re: Diesel Headcode Disc Positions...

Postby grovenor-2685 » Thu Feb 09, 2017 1:19 pm

Sorry, I had forgotten or never knew about the 1969 change.
Regards
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Keith
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Albert Hall
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Re: Diesel Headcode Disc Positions...

Postby Albert Hall » Thu Feb 09, 2017 7:37 pm

It is also easy to forget that we went through a phase with fully fitted freights whereby the brake van was abandoned and the guard travelled in the rear cab. Presumably on a double headed consist he would travel in the rear loco to keep a watchful eye on the trailing load. I cannot quote dates but it certainly applied during the 1970's when I attended my first fatal accident. That was a class 6 which ploughed into the rear of another train, the guard losing his life when the wagons behind piled into the rear cab. (Bridgwater, Somerset 1975).

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Re: Diesel Headcode Disc Positions...

Postby garethashenden » Fri Feb 10, 2017 6:24 am

Albert Hall wrote:It is also easy to forget that we went through a phase with fully fitted freights whereby the brake van was abandoned and the guard travelled in the rear cab. Presumably on a double headed consist he would travel in the rear loco to keep a watchful eye on the trailing load. I cannot quote dates but it certainly applied during the 1970's when I attended my first fatal accident. That was a class 6 which ploughed into the rear of another train, the guard losing his life when the wagons behind piled into the rear cab. (Bridgwater, Somerset 1975).

This one? http://www.railwaysarchive.co.uk/docume ... er1974.pdf

Albert Hall
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Re: Diesel Headcode Disc Positions...

Postby Albert Hall » Fri Feb 10, 2017 12:22 pm

That's the one albeit I was a year out. I have never read the official report but will do so thanks for the link. Ironically, had the guard of the train which was struck from behind not been in the rear cab of his loco he would no doubt have been killed instead as the rearmost wagons were all but destroyed on impact.


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