Antar Gallery

[radiomike7]

Would this be replacement for the Antars and Rottinofs in the oil industry

 

http://www.roadtransport.com/StaticPages/nicolastractomas.htm

 

That is the baby one, Rotran use a 10x10 version in Africa for heavy haulage.

[antarmike]

I wish to do a bit of "myth busting" regarding the Antar

As many of you know I own the Ex RAF Mighty Antar ex 40 AT 81.

 

I get no end of people referring to it as a Mk3 or a Mk3A Antar.

 

I wish to correct this myth . There was a separate model of Mighty Antar called the R6 (when fitted with the Rolls Royce C6TFL engine) or the R8 (Rolls Royce C8SFL)

 

The R6 is not a Mk3 Antar. It is a different model entirely. The R6 retained the 12 speed/ two gear lever arrangement of the Mk1/ Mk2. (the Mk3 had only 6 gears available for use) And like the Mk1/ Mk2 it had no third differential.

 

It had a fixed ballast body, identical to the Mk2 ballast box, and no fifth wheel. ( although there was a fifth wheel model of the R6).

 

It had the Darlington type 70 winch, not the Turner of the Mk3.

 

The transmission was different in as much as the Mk3 had the Main gearbox bolted to the Auxiliary gearbox. These being shaft driven from the Clutch, which bolted to the bell housing.

 

The R6 moved the gearbox onto the clutch bell housing, on the rear of the engine, and from there was a shaft drive to a separately mounted Auxiliary gearbox. The Mk3 had different gear ratios in under drive and overdrive, giving a higher road speed than the C6T.

 

The C6T was rated at a gross train weight of 140 Tons, but the Mk3 was only rated at 106.5 Tons.

 

The batteries lived under the passenger seat in the R6 not in boxes in the walkways around the winch as in the Mk3. The Air cleaners were paper elements above the offside wing on the R6 whereas the Mk3 had oil filled filters set into the wings themselves. However I am not sure of the Air filter arrangement on the Pakistan C6T's. These may well have had oil wetted filters set into the wings.

 

 

By kind permission of Thornycroft Society Ltd.

 

The above photo has appeared previously and it is sometimes captioned as a Pakistan Army Mk3 Antar.

 

However it is neither a Mk3 Antar nor is it a Pakistani Antar.

The Pakistan Army Antar are often captioned as being Mk3 Antars.

 

 

Both Thornycroft Society Ltd.

 

These two pictures have previously been posted on the message board, but I will refresh your memory, these are shots of the Pakistan army R6 Mighty Antars.

 

Looking carefully you will see that there are four windows in the back of the cab, on the Pakistan vehicles, Two large windows, one above the other, and a smaller window on either side of the top window. The windows are all protected by horizontal bars. The exhaust pipes are clearly visible, bolted to the front of the fixed wooden ballast body. This is clearly not the smaller, removable ballast box of the Mk3A. The fuel tanks have pressed sheet steel guards bolted to the skeletal frame.

 

Comparing these pictures of the Pakistan Army Antars with first picture in this post (wrongly identified as a Pakistan Army Mk3 Antar), you will see that picture shows only three unprotected windows in the back of the cab. There are no exhaust pipes visible. The fuel tank guards are skeletal. Referring back to the Argentina contract AEE Mighty Antar pictures below you will see these R6/ R8’s had the exhaust wholly under the vehicle.

Courtesy of Thornycroft Society Ltd.

 

The first picture in this post is actually another shot of the AEE model R6 Mighty Antars.

 

This Picture of the RAF Diesel Antar 40 AT 81 has been posted on this board before but elsewhere it has been described as a Mk3 Antar.

 

By kind permission of Thornycroft Society Ltd.

 

 

Extracts from the Manual for 40 AT 81show the model to be

 

Thornycroft Mighty Antar C6T.

 

The Electrical wiring Diagram shows the alternative designation of R6.

 

 

A view of 40 AT 81 taken from a similar angle as the Antar in the first photo in this post is shown above. Without doubt we are looking at an Antar R6 not a Mk3. Like the Pakistan Army R6/R8 there are four protected windows, but the fuel tank has skeletal guards.

 

The front on shot of 40 AT 81 has in the past been linked to the FV12007, a Mk3 Antar which was basically civilian fifth wheel tractor ,intended for use with a 20-Ton semi-trailer, but modified for military service.

 

40 AT 81 is a ballast tractor, not a fifth wheel tractor. It is not a civilian model modified for military service. It is almost identical to the 21 Pakistan Army Mighty Antars.

 

It is also identical to this Mighty Antar R6 , one of a contract supplied to a middle eastern Army.

 

It was not built to work with a Semi-trailer.

 

It was bought to work with the Standard RAF 50 Ton drawbar Dyson Plant trailer, as used behind the Mk1 Petrol RAF Antars.

 

 

I hope I have done enough to stop the model R6 or C6T being misidentified as a Mk3/3A Antar

Edited March 28, 2009 by antarmike

[antarmike]

Antar mythdebunking part 2 . The Mark3 transmission myth.

 

A myth is doing the rounds that the Mk1/ Mk2 Antar transmission, which was a four speed Main gearbox, driving into a three speed auxiliary gearbox, was totally redesigned for the Mk3, The theory goes that main gearbox and the auxiliary gearbox where combined into a single gearbox. The myth goes as far as identifying a Thornycroft code for the new gearbox. It was apparently either a G14/1 or a AG14/2, these being alternatives. The new transmission is described in this rumour as a gearbox with just six speeds.

 

I intend to dispel this myth by showing that there was no major resign to the gearboxes of the Mk 3 Tractor.

 

The earliest Antars had the Clutch bolted to the front of the main gearbox (which was a G14/1), which itself was directly bolted to the Auxiliary gearbox (an AG14/1)

 

Top photo shows clutch on right, Gearbox centre, Aux gearbox on left, all three being bolted together.

Lower picture shows other side of assembly.

 

The main and auxiliary gearboxes were separate units bolted together. Each had its own oil supply, Oil level, and drain plugs. There were no common oil-ways between the gearboxes.

 

The Mk1/Mk2 shared this arrangement with the early civilian Antars.

 

The Mk3 had the clutch unit unbolted from the front of the Mk1 /Mk2 Clutch/gearbox/Aux gearbox assembly. The Clutch moved to the back of the engine in a conventional bell housing and the drive was taken to the main gearbox ( again the G14/1) via a prop shaft. A separate Auxiliary gearbox was bolted to the rear of the main gearbox. The Auxiliary gearbox was a minor re-design of the AG14/1 now called the AG14/2.

 

Although this illustration shows a variation of the Antar C6T gearbox/Auxiliary gearbox assembly, the Mk3 arrangement only differs in the gear lever arrangement. In this view the Gearbox is on the left, Auxiliary gearbox is on the right.

 

The only difference between the AG14/1 and the AG14/2 was the ratios of the Auxiliary gearbox which became 1.608:1 in underdrive, remained 1:1 in Direct, but became 0.628:1 in overdrive.

The Ag14/1 of the Mk1, Mk2 and the C6T/R6 had gear ratios of 1.728:1 in underdrive, 1:1 in direct and 0.732:1 in overdrive.

 

Essentially the AG14/2 of the Mk3 was identical to the AG14/1 of the Mk1/ Mk2.

 

The rumour says the combined six speed gearbox of the Mk3 was Either a G14/1 or a AG14/2, suggesting that these were alternative Thornycroft descriptions for a combined gearbox.

 

Thornycroft used a very simple system G stood for Gearbox, AG stood for Auxiliary Gearbox. Whoever started this rumour does not seem to appreciate the system.

 

The A14/1 gearbox and the AG14/1 or AG14/2 Auxiliary gearbox were totally separate units. The G14 gearbox was bolted to the AG14 Auxiliary gearbox in the Mk3, but in some, but not all of the Antar C6T or the Antar R6/ R8 the two were unbolted. The G14 gearbox in this model was bolted to the Bell housing , from where drive was taken by a prop shaft to a separately mounted AG14/1 or AG/14/2 auxiliary gearbox. This proves the Gearboxes were not Combined in the sense I understand the rumour to be saying.

 

Lubrication drawing is a good place to see the G14 separated from the AG14.

 

(Other C6T variants kept the two gearboxes Bolted together. Having a clutch in bell housing on back of engine,/ propshaft/ bolted together main and Aux boxes ,exactly as in the Mk3.)

 

G14/1 gearbox showing it to be self contained.

 

AG14/1 (AG14/2 is almost identical) showing it as a separate item to the main gearbox.

 

So what had Thornycroft done, if they had not redesigned the gearboxes, and combined them in one unit?

 

They had simply redesigned the gear lever mechanism, inside the cab.

 

 

This Handbook drawing of the Gearbox/Auxiliary Gearbox assembly, shows two separate gear selector operating rods leaving the assembly, (top left of drawing) One comes from The main gearbox, the other comes from the Auxiliary Gearbox. (note the drawing describes the view as main and Auxiliary gearbox unit.)

 

The text on page 46 of the manual reads The main gearbox provides four forward speeds and the Auxiliary three, the change speed system being by a single lever.

 

This is the clearest statement that the Mk3 still had a four speed main gearbox driving into a three speed auxiliary box. An identical system to the Mk1 / Mk2, but with a change to the gear lever arrangement.

 

The drawing above shows two separate selector rods entering the Gear change box,( from the right) and a single gearlever. There was an internal interlocking system that allowed the gear lever to move between selector rods. Once fourth gear had been reached on the main gearbox, the same gear lever moves over sideways to engage the Auxiliary box gear selector, and then the Auxiliary boxed can be moved out of underdrive, into direct, and then into overdrive. Only when the gear lever moves the Auxiliary gearbox into under drive again , can the lever move across into fourth gear on the main gearbox, to effect further down changes.

 

This forces the gear lever to only access six of the 12 gears that are all still in the gearbox, available for selection, if only you could get past the interlocking in the gear change box mounted in the cab, above the bell housing. There has been no redesign of the gearbox. The only change it a very simple device to allow one gear lever to engage either of two selector rods, according a set allowed pattern of gear changes.

 

It is possible on a Mk3 Antar without doing any work the Gearbox, or Auxiliary gearbox, to uncouple the “new” gear change box, from the front of the selector rods and to fit two normal gearlevers and then you are back with all twelve gears within the two separate gearboxes again available for use as was the case with the Antar Mk1 / Mk2 and Model C6T/ R6.

 

The myth that the Mk3 had a redesigned transmission, replacing the old Gearbox/ Auxiliary gearbox , with a single new gearbox, containing six gears cannot be more wrong. There was a change in Auxiliary gearbox ratios more suited to the extra power available and a minor design change to the gear levers within the cab, and that is all.

 

I hope I have done enough to dispel the new, completely redesigned six speed, from a single combined gearbox, transmission myth.

 

Added 08-06-09 Sadly not, just bought a recently published book looking back on heavy Haulage, produced from recycled magazine articles (commercial and Military type magazines) and it contains this statement. In 1958 the mark 3 appeared...The transmission was simplified with a six speed main gearbox in place of the more complex 4x3 arrangement of the Mk1 and Mark2. Oh well... I tried.....

 

Added 30-12-09 Also quoting Army User handbook. (for those who still think there is only one gearbox!)

 

Power Take Off

Position... Top Of Aux Gearbox.

Edited December 31, 2009 by antarmike

[antarmike]

Myth busting 3 the role conversion of the Mk2 Antar

 

A few years ago it was suggested that like the Mk3 / Mk3A Antar, the Mk2 Antar was designed to be converted between the Artic Tractor and the Ballast tractor role. The claim is that the Mk1 Antar had a fixed steel Ballast body, and was only used as a ballast tractor, but the Mk2 was designed as an Artic tractor, and later a version came out of the Mk2 that had a removable wood/steel composite body.

 

The removal of this body would allow the Ballast Tractor Mk2 to convert to an Artic role, and when required the box could be put back on to resume operation as a Ballast tractor.

 

However only the Mk3A Antar was designed with a quickly detachable body.

 

The Mk3/ Mk3A was designed so the Ballast box, when unloaded , could be quickly removed from the vehicle (with only four attachment points to unbolt) to reveal a fully functioning fifth wheel and all the systems needed to connect and run an Artic Trailer. Equally a Ballast body could be dropped onto an Artic tractor, and when bolted down and Ballasted the tractor could immediately connect to a full trailer and drive off.

 

One reason why this was possible is because the wiring loom on the Mk3/3A was attached to the Chassis. However the wiring loom is attached, and passes through parts of the Mk2 Ballast body. Removing the body means cutting the wiring loom.

 

The Electrical difficulties of converting Antars between roles only mount because on the Mk2 Artic Tractor, the rear lights are on the back of the tool boxes, above the fuel tanks, approx two thirds the way along the Chassis. There are no lights at the rear of the vehicle itself.

 

On the Ballast tractor version of the Mk2 the lights are on the rear mudguards, which are themselves attached to the Ballast body. Removing the Ballast body therefore leaves the Antar with only part of its wiring loom and no rear lights.

 

There are two totally different wiring diagrams in the manual for the Ballast Tractor and the Artic Tractor.

 

Changing roles would involve a pretty major rewiring of the vehicle, not least because the ballast tractor had only one set of lighting sockets at the rear of the tractor, for full trailer operation. It did not have a second set of electrical connections just to the rear of the tool boxes, that were fitted only to the Artic tractor, so that the semi-trailer lighting cables could be plugged in..

 

A more fundamental reason why the Mk2 Antars can’t change roles, by removing the Ballast body is that the Antar Mk2 Antar for semi-trailer had a Hydraulic pump, mounted on the Auxiliary gearbox, driven by PTO. This lead to quick release couplings just ahead of the Fifth Wheel.

 

The Trailers the Mk2 worked with has Hydraulically operated tail ramps and jacks, but the trailer did not have a hydraulic power pack. The Tractor and couples trailer formed the complete hydraulic system. The trailer could not be used without the tractor mounted pump.

 

The Users Handbook WO Code 17769 says in the general description of the Vehicle,

 

Vehicles intended for drawing semi-trailers are fitted with a fifth wheel…and an hydraulic pump and connections for operating Jacks and ramps on the trailer.

 

And in section 18, the Hydraulic system it says

 

256. The hydraulic system on the tractor is only part of the complete system, the remainder being on the semi-trailer. The system is not fitted on vehicles with ballast bodies, as these are used only with independent trailer.

 

Removing the Ballast Box from a ballast box Antar leaves you with a Chassis without thie Hydraulic circuitry need to work the trailer.

 

The next fact that precludes a change of roles is the Mk2 Antar had two different braking systems, one for the Ballast tractor, one for the Artic.

 

The Artic shared the pair of palm couplings on the rear cross member, so both could tow a full trailer, but the Artic tractor had another set of palm couplings, mounted just ahead of the fifth wheel coupling.

 

For the Mk2 Ballast tractor to change role, there would be major reworking of the air braking circuitry, since these extra couplings would have to be provided.

 

The last reason that the Ballast tractor Mk2 could not be converted to Artic operation, simply by removing the Ballast body, is unlike the Mk3A, it had no fifth wheel. All versions of the Mk3/3a had a permanently fixed fifth wheel, and the ballast body was designed to fit over it.

 

It would not be possible to fit a fifth wheel to the Ballast tractor Mk2 having removed the Ballast box, because the Winch roller arrangement for the Artic, and the Ballast tractor were completely different

 

On the ballast tractor the winch rollers are carried in a vertical frame, one above the other, attached to the ballast body frame . On the Artic Mk2 the rollers are incorporated in the Fifth wheel ramps, bolted to the chassis . The ramps are intended to lift and guide the kingpin/ wear plate of the semi-trailer as it was coupled up. And because of the slope of the ramp, one winch roller could not sit above the other. The bottom roller is in a broadly similar position to the Ballast tractor version, but the top roller is roughly 18 inches further forward.

 

The Ballast tractor winch rollers would be unbolted from the chassis as the ballast box is removed. This leaves the Antar without rear winch rollers The Ballast tractor also has another pair of vertical axis pulleys bolted to the chassis, directly under where the fifth wheel would have to mount. These wheels are omitted on the Artic version, because of this clash.

 

So upon examination is a claim that the ballast bodies were removable from the Mk2 tractor , and it was possible to convert the Mk2 from the fifth wheel role to ballast tractor and back again?

 

I say no it was not. The Electrical systems, the lack of a hydraulic pump, the Air braking systems and the rear winch rollers make this totally impractical. Clearly, it could be achieved in a major rebuild, if the cost and time justified it, but certainly it was not a switch roles/ switch back again, as it was with the Mk3A were all the services were the same and contained totally on the chassis.

 

The Mk3A ballast body had four lifting eyes attached at the corners of the Ballast box, enabling it to be removed. The feasibility of taking the Mk2 Ballast body on and off, is called into further doubt, because no lifting eyes are provided, and the box has wooden walkways attached to the lower edges. Although these rest on the cross members under the ballast body, I feel the effect of trying to lift the box off with slings passed under the box, would be to pull off these walkways. If the ballast box was intended to be removed, it would have provision for lifting similar to the Mk3A ballast Box?

 

The Mk3A ballast box has four easy to reach attachment points to unbolt. The Mk2 ballast body is attached by 14 bolts! What does that say? How do you store the removed ballast body, it still has flimsy mudguards attached that hang below everything by several feet. You would need a purposed designed frame to sit it on, or spend more time unbolting the mudguards. (and further disturbing the integral electrical harness.

 

I feel this adequately dismisses the myth that the FV12003 Ballast version of the Antar could convert, by removing the Ballast body, into the FV12002 Artic version, and vice versa.

Edited March 29, 2009 by antarmike

[antarmike]

Myth Busting and the Antar part4 The Antar's FV3601 trailer

This is a widely published picture of an FV 3601 50 ton full trailer. This shot was taken from an MVEE catalogue.

 

I have heard it said that this is a Mk1 version of the trailer and you can tell the Mk1 trailers from the later marks because they were fully decked to carry other types of cargo other than tanks.

 

I would like to dispel the myth that you can tell a Mk1 transporter from later marks by whether they are fully decked or not.

 

This is an extract from the User Handbook for the trailer (W.O. Code 1879 with ammendment1) is shown below.

 

 

The most notable identifying features are the Mk1 trailer does not have a suspension point for the drawbar, so when uncoupled, the eye of the drawbar rests on the ground.

 

The Mk3 trailer, has the drawbar suspended when uncoupled.

 

The Mk1 trailer has a raised breather for the airbrakes, on the triangulated derrick at the front of the trailer. The Mk3 does not have this pipe.

 

These features of the Mk1 are clear in the above photograph, taken from the manual.

 

 

The photo from the MVEE catalogue shows the drawbar is suspended when uncoupled, and there is no breather pipe. It ,or photographs of other trailers, that have the drawbar suspension chain or do not have the raised breather are not of Mk1 trailers.

 

Are there other ways to tell a Mk1 trailer from later types? Yes

 

The plan of the Mk1 trailer in the handbook shows the deck of the trailer to be 10’ 0” wide. Extra bolt on angle sections bring the width out to 10’ 6” wide.

 

 

The Mk3 trailer has a one piece deck that is 10’ 6” wide. This leave the trailer with plain sides.

 

The bolt on angle that stretches the width of the Mk1 trailer by 6 inches is visible in this view, taken from the manual.

 

 

Note the 3” wide unequal angle has a series of triangular gusset plates reinforcing the top lip, as it is bolted onto the trailer, note also rope hook under top lip of angle.

 

A view of the deck of the trailer, also taken from the manual also shows a clear line, three inches from the edge of the deck, where this angle bolts onto the narrower deck.

 

To the right of the wooden scotch can be seen another identifying feature of the Mk1 Trailer. In the bolt on angle is a square socket.

 

These sockets were to carry 18 stanchions, that allow 41 chains to be rigged around the deck of the trailer to allow the safe carriage of boxed ammunition.

 

This feature was deleted on the Mk2 and Mk3 trailer, but these trailers remained fully decked.

 

 

Note in this photo from the manual, the angle along the side of a Mk1 trailer is very visible.

 

The picture above shows a fully decked Mk2 or 3 trailer.

 

This has to be a Mk2 or 3 since it has an extra roller, on the break over point, between the sloped deck, and the Beaver-tail. This roller was not fitted to the Mk1 trailer.

 

Another myth surrounding this trailer is that it had 10.00”x20” wheels.

 

The User manual WO code 1879 states

 

Tyre size 36in. X 8in.

 

The rumour I hear is talking about wheel size, not Tyre size, but I presume 10.0” X 20.0” refers to the tyre size.

 

To put things straight 36x8 equates in modern sizes to 8.25” x 20” (which is slightly smaller) or 9.00”x20” which is slightly larger).

 

10.00 x 20” is significantly larger and is not the closest match for a more modern tyre.

 

If the rumour relates to Rim width then again it is a myth that needs dispelling. I own a 50 ton Dyson trailer, still on its original wheels. The width of the wheel rim is 6 ½” I have just been out in the dark with a torch and a tape measure. If My trailer is untypical because it was RAF not Army, I welcome anyone else to go out and measure a nearby Dyson, and tell me if they find one that is 10” wide.

 

The wheels incidentally are a close match to the 36”x8” wheels of the early Leyland Hippo.

 

Regarding the braking system, most sources including the MVEE publication from which the first illustration is taken, say the trailer has a two line air braking system, operated from the tractor, and a mechanical handbrake, operating on the rear wheels only.

 

Technical descriptions often fail to mention that there was a second air tank on the trailer, whose secondary purpose was to provide air to a trailer mounted hand valve, that could apply all the trailer brakes, by air pressure. The idea being that the trailer could be separated from the tractor, if for example forward progress could only be made by the solo Antar, which having driven forward would then have winched the trailer up to the Antar. A brake man stood by the trailer valve and applied and released the trailers air brakes, to all wheels, as this process was repeated, until all the stored air in the Trailers tanks was used up. In practice this gives about 10 full brake applications. After this the tanks have to be recharged from the tractor. The hand valve simulates the tractor’s actions of putting air down the yellow service line when brakes are applied. I feel any full description of the tractors brakes really ought to include this information. The position of this hand valve is another way to tell the Mk1 transporter from later marks., but it is not normally possible to see the location of this valve on most photos.

Edited March 24, 2009 by antarmike

[antarmike]

Myth Busting and the Antar part5 Antar winches.

Thornycroft society Ltd.

 

It has got around that the above pictures show a “definitive” FV12003 Fifth wheel Mk3 Antar .

 

I do not know why this Antar isn’t built to the Mk3 Antar spec, but two factors at least mean that it cannot be regarded as the “Definitive” Mk3. It varies in two ways from the standard production FV12004. The Batteries should be in boxes let into the walkways, above the fuel tanks, and they are not.

 

(I suspect this Mk3 may have the batteries back under the passenger seat).

 

However there is a more fundamental reason why this vehicle cannot be considered “definitive” is that it has a non standard (for the mark) Darlington type 70 winch fitted, not the normal Turner expected on a production Mk3 Antar.

 

Below is a line drawing of the Mk3 Turner winch.

There is no resemblance between this winch, and the one fitted to the vehicle above.

 

The 1963 Commercial Motor show Antar specially prepared by Transport Equipment Thornycroft (TET 1963) is carrying the same winch as the one on the photo below,. This winch has in the past been published with the caption that it is a turner winch fitted to a Mk3 Antar.

Thornycroft Society Ltd.

 

 

The vehicle is not a Mk3, it is a C6T/ R8 (see separate post) , but the winch is a Darlington type 70 the type fitted to the Antar C6T/ R6, not a Turner winch.

 

Here are two line drawings from the Antar Model C6T/ R6 Handbook showing the Darlington type 70 with and without spooling gear.

 

Thornycroft Society

The same winch is shown in the photo above, and has on occasions been associated with a comment to the effect that British Army Mk2 Antars did not have spooling gear fitted as this one does.

 

I believe there is no reason to suggest MoS vehicles did not have spooling gear to the Darlington winch.

 

The User Handbook for the Mk2 ( amendment 4 , section 75 Paying out the winch cable) says that disengaging the Dog clutch, upsets the synchronisation between the drum, and the paying on gear, and the dog should be left engaged to avoid this.

The Lubrication Diagram for the winch in the same handbook shows the lubrication points on the paying on gear.

 

A picture has been published of a British Army Fv12002 Mk2 during wading trials that shows that paying on gear (spooling gear) is fitted. (the relevant detail of which is reproduced below.)

Parts book for the Mk2 shows Makers part number 70/31/P26 Winch assy. W/pay-on gear M.T. part number LV7/DW/70/31/P26

 

Here for information is the range of Darlington winches Available.

I put this Darlington winch info on the board for your consideration since another myth I want to dispel is that the Mk1 Steel bodied Antar was fitted with a Darlington type 70. I believe the Mk1 actually had a Turner winch. Although not the same model Turner as the Mk3. I remember climbing over the REME Museum Mk1and feel sure that the winch plate said Turner! However whatever it is the Mk1 Steel ballast bodied Antar does not carry any model of the Darlington type 70

The Mk1 winch for comparison. Clearly NOT a Darlington type 70!

Edited February 5, 2010 by antarmike

[Guest catweazle (Banned Member)]

Wow you could write a book with that lot.No wonder Tom Thornycroft stuck to boats.:-D

[antar]

Quite impressed Mike, I thought I knew a bit about Antars, but the above even taught me a few things. About time someone corrected all the errors in a certain publication a few years ago !!!

John.

[antarmike]

Myth busting and the Antar part 6 Fifth wheel loading

 

A story is circulating saying that The turntable of the fifth wheel was intended to carry a maximum load of 34 Tonnes.

 

It is my opinion (though it may not be the opinion of the Forum) that this figure is incorrect.

 

User Handbook for the Mk2 Antar gives on Page 17 an Unladen (tractor only) weight of 19 Tons 6 Cwt.

 

It gives a Laden weight (tractor, plus imposed load of trailer and load of 51 Tons 0 Cwt.

 

Taking the unladen weight from the laden weight gives 31 Tons 14 Cwt.

 

This is the Maximum imposed load on the Mk2 Artic tractor‘s fifth wheel.

 

The manual for the Mk 3 gives (page 10) Laden weights NOT to be exceeded of

Front Axle 10.65 Tons

Rear Bogie 40.9 Tons

 

Giving a Maximum laden weight of 51.55 Tons or 51Tons 11 Cwt.

 

It gives an Unladen weight (page 11) for the Mk3 Antar of 21 Tons 0 Cwt

 

Taking the Unladen Mk3 weight from its maximum laden weight gives 30 Tons 11 Cwt.

 

This is the maximum imposed load permissible on the Mk3 Tractor‘s fifth wheel.

 

How do these two figure compare to the 34 Tonnes that the rumour states the Antar fifth wheel can carry?.

 

Taking a conversion factor of 1 Ton = 1.01 Tonnes,

 

34 Tonnes equates to 33.663 Tons or 33 Tons 13 Cwt.

 

It is my opinion that the loading capability of 34 Tons is wrong for both the Mk2 and the Mk3, Antar which vary slightly, but neither can reach his figure.

[antarmike]

Myth busting and the Antar part 7 Loading AFV's by winch

 

REME Museum

 

This picture has appeared elsewhere captioned to the effect that although a winch operator is at the controls of the winch, there is no winch rope visible. But it Appears that the AFV is being winched onto the trailer.

 

For someone to say that the winch rope is not apparent, it shows a general unfamiliarity with winch loading of AFV's and where to look for the cable.

It is normal practice to pass the rope under the tank to pass round a pulley block attached under the tank to the rear towing shackles. The rope is reeved several times back an forth to another pulley block attached to the front of the trailer.

 

The winch rope comes from the Antar, through the centre of the triangular derrick on the front of the trailer, passing over a roller just above the deck of the trailer.

 

If anyone is expecting the rope to go to the front towing shackles, and expects to see it higher of the trailer deck, then they will miss the winch rope in the photo. However the winch rope is perfectly visible in the photo if you know how a tank is loaded by winch onto one of these trailers. (Ie with the attachment point at the rear of the hull, the rope lays under the belly plates.)

 

It is my opinion that the winch rope is apparent in the photograph, , as is half of the snatch block!,and the line of the rope follows the angle of the trailer deck, and is a few inches above thie deck. In fact you can see several returns of the rope, as it passes back and forth between pulley blocks.

 

I suspect it is unfamiliarity with tank loading methods that may have lead to the mis-captioning of the photo to say the winch rope is not visible.

Edited March 25, 2009 by antarmike

[antarmike]

Myth busting and the Antar part 8 the Electrical Equipment.

 

A myth is circulating that with the exception of the rear lamps, which for some reason, used Conventional chassis-earth return, all components were connected using double pole wiring.

 

Is this statement Correct?

 

The Wiring Diagram for the Mk2 shows that the Headlamps, Turn lamps Slave socket, inspection lamp socket, Instrument panel warning lamps, booster coil etc. also use Chassis-earth return.

 

The drawings for the Mk3 Antar clearly shows ALL lamps and ancillaries employ conventional chassis-earth return.

 

Another related myth states the Antar had a 24Volt negative earth system. Mk1/Mk2 vehicles had either four 6V 110Ah Batteries or 18 separate 1.5 Volt 160 Ah cells.

 

18 1.5 volt cells does not give a 24 volt system.

 

If the vehicle had seperate 1.5 Volt cells there would be 16 not 18 of them.

 

The myth goes on to say that documentation suggests the Mk1 RAF Antars were fitted with six Nickel-Cadmium alkaline (NIFE) batteries, each consisting of 3 cells.

 

This gives 18 cells in total which is right for NIFE cells since each cell produces a lower voltage than the Lead Acid cell, so more are required.

 

However NIFE cells are not Nickel-Cadmium Alkaline cells, They are Nickel-Iron Alkaline Cells. (Fe, as every school kid knows being the Chemical symbol for Iron {Ferrous})

I hope that clears up any misunderstanding about these aspects of the Antars electrical equipment.

Edited March 25, 2009 by antarmike

[antarmike]

Myth Busting and the Antar part9 Self Recovery

 

A myth has circulated for some time saying the winch winch was provided for the purpose of loading and unloading disabled AFV’s to the vehicles trailer, rather than for self recovery, and no provision was made for winching from the front of the vehicle.

 

Although this staement may be true for many Antar models, it is not true for all of the Antar Production.

 

The RAF mark 1 Antars differed from the Army Mk1 by being able to self recover using the winch fed out under the front bumper.

Rear view of an RAF Petrol Antar shows a third winch pulley. (two pulleys are placed paired centrally further forward in the chassis, ahead of the horizontal guide rollers)

Thornycroft Society

The Army version did not have the third left hand pulley. The winch could not feed to the front.

MoD

The RAF Antars that transferred to the Army gained ZB registrations. Here 75ZB98 shows that the winching forward capability was retained on transfer. Note the winch rollers hanging under the front bumper. The Army, as well as the RAF had models of Antar clearly designed to winch to the front for self recovery.

 

47AN09 Thornycroft Society

Note again rollers under RAF front bumper. But this Thornycroft works photo was taken before the Turner winch was fully fitted.

[croc]

Interesting reading Mike, I was unaware that there was so much misinformation circulating.

[antarmike]

Some sources of information are accurate, others are less so,....

[antar]

Some sources of information are accurate, others are less so,....

 

Can't possibly imagine who or which publication you are refering to Mike ????

John.

[antarmike]

47AN09 Thornycroft Society

Another myth (10) is that this photo shows the Antar with the winch brake clearly visible, even though the winch is not Fitted.

 

The Thornycroft Antar had a forward reverse PTO to drive the winch, allowing it to power out as well as in. The lever we see here engages the PTO in either direction, and is part of the Antar, as built by Thornycroft.

 

The winch fitted to this model had two sligtly different brake arrangements, on different chassis' . On some winches the brake band was wound tight by a hand wheel. The handwheel is visible on this shot of a ZB Antar

MoD

and also on the REME Museum Antar

 

On others a second lever worked the brake . This lever, which is part of the winch, sat alongside this lever (Thornycroft built PTO engagement.) The second lever is integral with the winch, and would only be visible, when the complete winch was bolted onto the chassis!

 

 

As I say don't beleive everything said about the Antar, even if you see it in print.

 

On the Mark2 and C6T Antar this PTO engagement lever moved into the cab, from where all the other winch controls were to be found.

 

On the Mark 3 this lever, found in the cab also selected the Hydraulic pump drive.

 

The photo immediately above also shows 02 BD 16, and this Antar now has a single lever. Can I suggest that there was a delay in sourcing winches and many photographs exist of the Mk1 Antar with no winch fitted. I beleive there were problems with the winch brake, and that 02 BD 16 did not remain in this form for long but the winch was reworked, the unstaisfactory lever operated winch brake being replaced with a brake band wound on with a hand wheel.

Edited May 20, 2009 by antarmike
I can't spell

[antarmike]

Myth busting and the Antar part 11, the steering sytem.

 

This rumour says says the steering gear was "partially redesigned" on the Mk3 to overcome shortcomings with the Mk2 steering.

 

Here is the Mk2 system,

 

Now for the Mk3 system

 

 

The Mk 3 Manual, shows that the Hydraulic pump has been moved to inside the front bumper, driven directly from the crankshaft, so it runs at engine speed. It used to be gear driven in the Mk2. The two single acting pistons on the LH side of the vehicle are replaced by a single double acting piston on the RH side. But the actuating valve is now incorporated actually as part of the steering box, instead of a remote unit, operated via a relay arm.

 

The new system is easier to maintain, as it has become self bleeding, and doesn’t need the bleed screws that had to be attended to whenever work was done on the old Mk2 steering, and air got into the system.

 

Whether you view this a "Partial redesign" or a totally revised system, with no common components whatsoever, I will leave to your judgment. The systems seems totally different to me.

 

The Antar C6T/R6 uses the Mk3 system, virtually as drawn here. for which I am very greatful, the Mk2 Antar suffered from loss off power assistance at low engine revs, the secret of driving being to keep in low enough gears to be able to rev the engine quite fast when turning is to be effected. The C6T is not as bad and although there is some loss of assistance at tickover, the system provides far more help at low revs than the Mk2 ever did.

Edited March 27, 2009 by antarmike

[antarmike]

Myth Busting and the Antar 12

 

This myth says the military called the Antar the Antar not the Mighty Antar, a name associated with some of the commercial models. The myth goes that by the late fifties Thornycroft were using the name Antar for the 80 ton 6x4 tractor and Mighty Antar was only used for the 30 ton payload Oilfield tractors.

 

The RAF plate from inside my cab 1961

Thornycroft manual

Meteorite parts book

Edited December 31, 2009 by antarmike

[antarmike]

Curious method of attaching plate to fibre glass inner skin of the cab....good old Thornycroft!

[antar]

Ex Beverley ANTAR'S and Dyson trailer have just re-emerged virtually on my doorstep, see latest copy of MMI. Will post more info when I have it.

[Rick W]

Antar I think? Apologies if it isnt!

[antar]

Certainly is, a Mk 3 with Sankey 60ton trailer.

[antar]

Ex Beverley ANTAR'S and Dyson trailer have just re-emerged virtually on my doorstep, see latest copy of MMI. Will post more info when I have it.

 

Spent all day Friday getting the Mk 3 running, there are some electrical problems and there are no belts on the compressor so could not build up its own air.

 

The trips in the distribution box are both faulty, the 10A has already been wired out with an external 10A fuse, the 30A one pulls the coil in as soon as any load is put on it, so I think the main contact must not be made. This will get modified into someting more modern.

 

Hot wiring a positive supply to the SOL wire engaged both starters but without pulling in the contactors on the starter control panel so no rotation. Removed the cover off the starter control panel and pushed each contactor in by hand, each starter works perfectly well and the engine turned over.

 

All other checks carried out oil, water ect, fuel primed up and this time when the contactor pushed in the engine started after half a turn.

 

Next I hooked up an air line to the front emergency coupling and charged the air system up to 100 psi. With the new owner in the cab for his first ride in a MK3 ANTAR we were off around the yard. Two circuits of the yard and we were back to charge the air system with the air compressor. This time the new owner had his first drive, he soon had the hang of the gear change getting up into 5th without any problem.

 

There is still plenty of work to do but basically the truck is in full running order.

 

The Mk2 is in very nice condition from a bodywork point of view but was misfiring badly on the day I was there, the new owners nephew was busy most of the day removing all the spark plugs for checking and cleaning.

 

John Riley

[6 X 6]

With the new owner in the cab for his first ride in a MK3 ANTAR we were off around the yard.

 

 

Thanks for your report, and pictures, of what must have been a very enjoyable day spent with two very nice looking Antars. :thumbsup:

[gritineye]

John Attlee at Beltring, having trouble with the jack legs that kept sinking in the ground, despite stacks of timber under them, very hot work. :sweat:must have been the hottest day for years.