Trailer, Dummy Axle, Recovery, 10/30 Tonne

[MilitantGraham]

I've just bought one.

I only know of five, including the one at the REMEmuseum . Mine is the only one I have seen at a rally after I collected it on the way to Hanbury this weekend.

It all seems to work OK. There's a few odds and ends missing and it's covered in moss, but I should have it ready for work and show by next year.

 

http://www.aecmilitant.co.uk/pictures/dolly1.jpg[/img]

 

http://www.aecmilitant.co.uk/pictures/dolly2.jpg[/img]

 

Has anyone got any pictures of one in use or any information on them.

I believe they were intended to tow a fully ballasted Antar at 32 tons. Would they tow the trailer and Centurion at the same time, the full 102 tons ?

What about the half shafts ? The outer rear wheels on an Antar are mounted on the half shaft flanges. This give three options;

1 Remove the outer wheels and half shafts, overloading the inner wheels.

2 Remove the outer wheels and halfshafts, fit four dummy half shaft flanges, refit the wheels.

3 Tow it with the half shafts in, back driving the worm diffs and epicyclic gears.

 

The front wheels of the Antar would need to be removed to clear the trailer wings as the trailer relies on bringing the weight up over its own axle, not hanging it out the back like a recovery vehicle. That's why it can lift twice as much as the Militant.

[Mark]

That is a nice looking bit of kit the Militant, how old is it Graham

[MilitantGraham]

All Militant Mk3 Recoverys were built in one batch of about 200 around 1969/1970.

The FJ registration on the towing dolly was issued in 1969/1970 as well.

The chassis number is "ROFN No4". I'm guessing it was built by either the Royal Ordnance Factory or Rubery Owen.

I think I'm going to have to make another photcopying trip to the REME Museum over the winter to get some more information.

[Richard Farrant]

 

The chassis number is "ROFN No4". I'm guessing it was built by either the Royal Ordnance Factory or Rubery Owen.

 

 

hi Graham,

 

Your Dummy Axle was made by Royal Ordnance Factory, Nottingham. Going back to your first message, I do not think it was intended to tow the full Antar and trailer, although there were times when Scammell EKA 's towed full trains in order to clear obstructions. In the SEME Recovery Data, it lists recovery of a fully laden Antar and semi trailer as N/A, a tractor on its own would require a front lift of 5.5 tons, rear lift being 8 tons 8 cwt, which could be reduced by 1 ton, which may indicate removing rear wheels (?). Using a dummy axle for a Antar plus trailer, would not impose any weight on to the driving wheels of the towing vehicle, so lack of traction could occur. My only experience of this Dummmy Axle was load testing them when working in REME workshops.

 

Richard

[MilitantGraham]

Thanks Richard. I'd never really thought much about ROF before and assumed there was only one, probably at Chertsey or Chobham. I just looked it up on Wikipedia and there were dozens of them. I've learned something new today.

 

The figures you quote are for the Semi-Trailer Antar. I thought the Dummy Axle trailer was for towing the Ballast Tractor Antar, looking at these pages taken from www.aecmilitant.co.uk/downloads/recoverymanual.pdf it looks like it was capable of doing so, but only from the front.

 

http://www.aecmilitant.co.uk/pictures/temp/recoverymanual297.jpg[/img]

 

http://www.aecmilitant.co.uk/pictures/temp/recoverymanual298.jpg[/img]

 

I assume the second "a. Front" under 3 should read "b. Rear" and the asterisk means that the Antar chassis would not stand having most of its 36 tons suspended from the extreme rear end.

[Richard Farrant]

 

I assume the second "a. Front" under 3 should read "b. Rear" and the asterisk means that the Antar chassis would not stand having most of its 36 tons suspended from the extreme rear end.

 

 

Graham,

 

According to my data here, your assumption is correct, "b" is rear. Also, it appears that a rear suspend could only be done when the 10 ton ballast load is removed, bring vehicle rear suspend weight down to 11 tons.

 

Richard

[antarmike]

My Antar is 32.5 Tons, that is 10.5 tons on front Axle, 12 Tons per rear Axle.

 

Because you are lifting from the front bumper the load would be a little less, but I can't see how it can be 5.5 Tons.

 

Lifting the rear end needs to raise both axle clear, and that is 24 Tons, or very slightly less cos the rear end lifting points are only a very short distance behind the rear axle.

 

I am only carrying 12.5 of the max 15.5 Ballast that was intended.

 

[Richard Farrant]

 

Because you are lifting from the front bumper the load would be a little less, but I can't see how it can be 5.5 Tons.

 

 

 

hi Mike,

 

Just checked the REME recovery data again, and the Unladen figures I quoted were for a Tractor, semi-trailer, 30 tons, Mk3., with a GVW (unladen) of 21tons 5cwt.

 

Now the info here for the Mk3 with ballast body is as follows;

Fully laden

Front suspend tow, 6t 10 cwt

Rear suspend tow, N/A

GVW 36 tons

 

Unladen

Front suspend tow, 4t 15cwt

Rear suspend tow, 11t

GVW 22t 14cwt

Rear suspend can be reduced to 10tons, (assume this is by removing the wheels?)

 

 

I am only quoting from the Recy Mech training book.

 

Richard

[antarmike]

The axle weights I am using are the figures from the Ministry of Transport weighbridge at Didcot, when I got pulled in for being (alledgedly over length...When they found nothing wrong with my length they decided they would try axle weights and that didn,t work either....

 

What I don't understand is My antar is a C6T.

 

I have two less cylinders than the Mk 3 and the Turbo has to be lighter than the Supercharger on the Mk3.

 

Admittedly my gearbox being bolted to the back of thew bell housing is further foward than the Mk3 where there is a shaft between the clutch and the two remote gearboxes, so how come my front axle weight is that much higher than the Mk3?

[Richard Farrant]

Mike,

 

You cannot disagree with a Ministry weighbridge test results. I checked the MVEE vehicle data book and that coincided with the REME recy data.

 

Have you found any manuals, data, etc on your specific model of Antar?

 

Richard

[Richard Farrant]

Mike,

 

I have just noticed something in your earlier post, the sum total of both rear axles and front comes to 32.5 tons, where as the recovery data gives front and rear lift weights, which added together to not come to the gross weight. Looking at other vehicles in this recy data, they also do not add up.

An example;

Saracen

Front lift 3 ton 19 cwt

Rear lift 3 ton 19 cwt

GVW 10 ton 4 cwt

 

(On this vehicle, when doing a lift from either end, the centre axle has to be free of the ground, and centre wheels removed)

[antarmike]

But lifting from the front end you have a mechanical advatage. ( a lever if you like.

 

The Centre of gravity is somewhere between the axles. The weight on the front axle is greater than the force needed to lift the front of the vehicle from the bumper simply because the axle is nearer the CofG and the Bumper is further away. the longer the handles of your weheel barrow the easier it is to lift and push the same load in the barrow.

[antarmike]

Manual, yes and no. The Antar was picked up from Basingstoke by Geoff markaham and he was the only RAF driver. After 2 years the antar transferred to MPBW and Geoff was given a civvy job. He stayed with the Antar for a couple of year but then they moved him. He was so miffed they had taken "His" antar that he kept the manual.

 

Forty years later I got to hear of him and rung him up. We chatted and got on and without warning he said "I have the original drivers handbook, do you want it"

 

What could I say

[antarmike]

Managed to get A C6T Antar Tech Handbook from Thornycroft Society, largely useful but the model in the handbook has engine/ clutch as unit, prop to remote Main and Aux boxes which form another unit, mine has engine/ clutch/ main gearbox as unit then prop to remote Aux box which sits on its own. otherwise manual is useful..