Why Gun Tractor Shape

[Lang]

I have often wondered why gun tractors have such a weird shape. If there is one thing an artillery tractor needs to do is to carry lots of stuff (not only ammunition but crew gear, tents and all the other gear that Artillery people can not live without).

It seems to me that if they built them with a decent standard back they could almost dispense with the limber which must have driven the crew insane with no reversing ability, completely destroying any cross country ability with 90hp trying to drag not only a gun but a heavy trailer as well, finding parking places for such long combinations would have required extra effort.

It would take much longer to come into action having to deal with two heavy bits of equipment instead of one just getting its ammunition directly out of the back of the tow vehicle.

They obviously found it inefficient as limbers are long gone and it would appear that by the end of WW2 they had been replaced largely by more efficient standard trucks.

Artillery people - Is it just fashion or why?

Lang

[Mike Cecil]

Hi Lang,

I think there was a thread about this subject some time ago that explained the odd shape. Can't locate it now, but I'm sure Hanno can (if my memory is right!)

Aust field artillery tractors parted from the British 'odd shape' by being 'full bodied' (Nos 1,2,3, with rag roof, Nos 8 & 9 with solid body) but still used the artillery trailer until the end of WW2, when only the No.8 & 9 were retained, and the trailer No.27 Mk.1 was dispensed with.

CCKW353 and 'tractors, tracked' were also employed by Australia as field artillery tractors in the latter period of WW2.

The No.8 & 9 tractors were retained into the 1960s being used by the CMF. (Whereas the Regular Army had moved to the GMC CCKW353 and Studebaker US6 as tractors).

Mike

[Lang]

Bruce

Could be, but why retain it when the 25 pounders had self-contained rings?


Thanks Mike

When I was a 17 year old kid I was a member of 11 Field Regiment (CMF) in Queensland in 1964. Our battery (at Southport) had GMC's while the rest of the regiment had replaced them with Studebakers.

The GMC's had been in use for many years in our unit. I remember watching them from the classroom window (the Army depot was next door to the primary school) when I was only 13 or 14.

The only Blitz I ever saw on any exercise was a long-wheelbase water tanker from the central transport pool, not a regiment vehicle. I was the 2i/c's driver in a Landrover and remember we had to regulate the speed of the entire GMC/Studebaker/Landrover regiment convoy the whole 300km to Tin Can Bay to cater for the poor old blitz.

A regular Army unit would probably have blasted off as normal and given the Blitz a free-running licence to get there in his own time. At worst they would have put him in the last packet so only a few vehicles had to suffer the pain.

Lang

[Bruce Parker (RIP)]

Just a guess but I expect the traversing base for the 18pdr was stowed on the back roof and the slope was to let the gunners manhandle it up there.

[David Herbert]

At the start of WW2 they had only just moved on from pulling guns with horses. The limber was there to carry the tools and ammo. The tractor was just to pull it and carry the crew and their kit. It needed to be manoeverable so was as short as possible and easy to hide when the gun was in action. As the war went on the thinking changed and tractor and limber morphed into a full sized truck.

David

[Mike Cecil]

Interesting, Lang. Always good to have first-hand observation.

The Studebaker was the front-line, overseas deployable truck for the regular army from the late 50s (when they were pulled out of storage) until progressively replaced by the No.1 Mk.3 Inter 2.5 ton trucks from the early 1960s.

By 1964, sufficient Studebakers had been replaced in reg units by No.1 Mk3 Inters to see them with CMF units, as you observed. In Victoria, 2 Fd Regt remained with CCKW353 and Tractors No.8 & 9 until the early to mid-60s. Don't remember ever seeing Studebakers with 2 Fd Regt, and as a young lad, I was a frequent visitor (father was BSM, Q Bty) but I may be wrong - it was a long time ago. Studebakers were retained until sold off in the early 1970s. I wrote an article on their Aust use a long time ago, for Army Motors. I think there were about 1,300 in total in Aust service.

Still, that is getting us away from your original question: why the odd shape of the British FAT? (Morris, CMP, Guy, etc)

Mike

[Dan Martel]

Originally Posted by David Herbert

At the start of WW2 they had only just moved on from pulling guns with horses. The limber was there to carry the tools and ammo. The tractor was just to pull it and carry the crew and their kit. It needed to be manoeverable so was as short as possible and easy to hide when the gun was in action. As the war went on the thinking changed and tractor and limber morphed into a full sized truck.

I think Dave has hit the nail on the head. The first tractor-limber-gun set was made to replace the horse-drawn set, and the horse-drawn set didn't carry anything but two members of the gun crew. A tractor could carry the entire crew. A real step forward for the Artillery. Large trucks capable of carrying men, equipment and ammunition were in short supply in the late 30's, and not as capable as they would become later in the war.

The C8 tractor was designed to replace six horses and three riders, and tow the limber and gun, nothing more. The Artillery wasn't looking to make radical leaps in technology at that time, but in a couple years they would be leading the Army in change. and had the trucks to prove it.

Just my 2 pfennings.

Cheers,
Dan.

[Lang]

Apart from the 18 pounder ring theory (later replaced by a spare tyre carrier)
why did they continue to have the strange shape cutting their potential load and usefulness by 50%.

The same number of people were in the crew regardless of horses or trucks. The riders were all gun crew members just like later gun-truck drivers are also just a member of the crew.

The short wheelbase theory does not explain the sloping back as a square box would hold so much more on the same wheelbase.

I am currently of the opinion it is one of those mindless "we have always done it that way" decisions to continue to produce that shape after the traverse ring storage problem had long passed.

Lang

[rob love]

I think Bruce had it right. The early trucks had run flat tires so no need for a spare. The ring for the 25 pounder was not kept on the gun for any long distance...it was stowed on that slanted back. After Burma fell, and rubber became scarce, the vehicles were built without runflats, so needed a spare. At that time the stowage location for the firing platform went onto the top of the limber, and the spare tire location was the slanted backside of the truck.

The move to mechanization was the death of the limber. As mentioned, the limber removed the weight of the gun trail from the backs of the horses. But with mechanization, the towed loads actually need the weight on the hitch for stability. And why not just build a bigger truck so you can carry all the ammunition, tooling, and the gunners kit as well as the gunner? The limber also would have made it a real bitch to back up more than a couple feet.

The Canadians actually built artillery tractors in the early 30s out of locally sourced Leyland trucks. The purpose built DND designed bodies had a large stowage capacity, but the setup still retained the 18 pdr limber. I suspect that when we started building trucks for the British, we ended up following their basic design of the artillery tractor.

[Lang]

Why didn't somebody say "Give us a proper truck so our regiment workshop guys don't need to build racks on the sloping back to carry all the required gear".

[Richard Scott]

Originally Posted by rob love

I think Bruce had it right. The early trucks had run flat tires so no need for a spare. The ring for the 25 pounder was not kept on the gun for any long distance...it was stowed on that slanted back. After Burma fell, and rubber became scarce, the vehicles were built without runflats, so needed a spare. At that time the stowage location for the firing platform went onto the top of the limber, and the spare tire location was the slanted backside of the truck.

The move to mechanization was the death of the limber. As mentioned, the limber removed the weight of the gun trail from the backs of the horses. But with mechanization, the towed loads actually need the weight on the hitch for stability. And why not just build a bigger truck so you can carry all the ammunition, tooling, and the gunners kit as well as the gunner? The limber also would have made it a real bitch to back up more than a couple feet.

The Canadians actually built artillery tractors in the early 30s out of locally sourced Leyland trucks. The purpose built DND designed bodies had a large stowage capacity, but the setup still retained the 18 pdr limber. I suspect that when we started building trucks for the British, we ended up following their basic design of the artillery tractor.

I have some memory that the odd Shape was for the ease of chemical decontamination?

[Richard Scott]

https://www.awm.gov.au/collection/C2135093

The 'beetle back' pattern was so named because of its distinctive sloping rear section, manufactured between 1938 and 1944. The unique shape was derived from a design to make the vehicle easier to decontaminate in the event of a gas attack. The 'beetle back' Quad is believed to be the only vehicle to employ this design feature.

from Australian War memorial web site

[Lang]

Ah, the origin of the gas decontamination furphy. There are hundreds of misnamed or misidentified photos and objects in the AWM. Mike Cecil would know more than most that a degree in museum or film conservation does not a military expert make.

Apart from the fact the sloping back made almost no difference to any washing with 2/3 of the upper surface still horizontal, a division might have 3,000 vehicles but the only ones they wanted to wash down easily were 100 gun tractors?

Lang

[Hanno Spoelstra]

To add to the confusion, some sources state the "The Canadian Chevrolet CGT Artillery Tractor came with both a fully armored cabin and a partly armored one"

Hope the confusion is complete now!

H.

[Mike Cecil]

Lang,

To be fair, the AWM were not the originator of the furphy about the shape being for gas decontamination, but made the error of quoting an otherwise reputable source without checking or thinking about it. The origin, as far as I can make out, was as indicated by this post in another MLU thread:

"Reference to the design shape is contained in a Mechanisation Board minute featured in Ventham and Fletcher’s Moving the Guns : the Mechanisation of the Royal Artillery, 1854-1939, p81...."

And I agree with you: just because an individual is in the employ of the AWM (or any other military oriented museum) does not mean he or she has a sound knowledge of military matters or history.

Mike

[Hanno Spoelstra]

Originally Posted by Mike Cecil

The origin, as far as I can make out, was as indicated by this post in another MLU thread:

"Reference to the design shape is contained in a Mechanisation Board minute featured in Ventham and Fletcher’s Moving the Guns : the Mechanisation of the Royal Artillery, 1854-1939, p81...."

Here is a cross link to the relevant posting in the thread AWM acquisition?.

Thanks for bringing that source up again, Mike.

HTH,
Hanno