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If you want to read more about there, there is a very good interview with the people concerned in this book.

https://www.amazon.co.uk/Brixmis-Untold-Exploits-Britains-Mission/dp/0006386733/ref=sr_1_2?keywords=brixmis&qid=1563348953&s=gateway&sr=8-2

 

As you will see reading it, we had plenty of technical data of Soviet equipment from digging through their rubbish dumps. Its cerainly possible they had enough to inspire them to replicate an autoloader I suppose, or at least elements of one. I dont think it can have been much more than that, I just dont see where we could have got hold of one and picked it apart. T64's were pretty rare on Ebay in those days as I recall. :)

Thanks Stuart. Your recommendation for 'Tank Factory' was spot on - great read.

 

Ebay is dangerous - don't think the wife would be impressed if I stuck an AFV on the drive!

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Is it possible that this is not a British autoloader project, but a design study to envisage how a Soviet autoloader worked, and figure out what the rate of fire might be? Has this been confirmed as being part of the pip project mentioned above? Because ive seen no tinware of that project existing anywhere, not even a model in the Tank museums collection.

 

Just an idle thought.

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Is it possible that this is not a British autoloader project, but a design study to envisage how a Soviet autoloader worked, and figure out what the rate of fire might be? Has this been confirmed as being part of the pip project mentioned above? Because ive seen no tinware of that project existing anywhere, not even a model in the Tank museums collection.

 

Just an idle thought.

I have that idea, too. Because "the thing" looks so unfinished and uninspired.

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  • 1 month later...

Burlington bisquit no.4 (1968)



25mm steel -/air gap/ 6,35mm polyester on 6,35 steel plate-/air gap/ 6,35mm polyester on 6,35 steel plate-/air gap/ 6,35mm polyester on 6,35 steel plate-/air gap/ 6,35mm polyester on 6,35 steel plate-/air gap/ 6,35mm polyester on 6,35 steel plate-/air gap/50mm backplate whole block 16 inch thick



and side modules is 1-2mm stainless steel 3,175-6,35mm plastic, whole block 8 inch thick



16" block when it's sloped at 60° gives protection from 6" HC(643mm pen) and from 120mm APDS is equivalent to 136mm of RHA(both by weight and by level of protection)



TcNx7U827IA.jpgwKrXAusA2WY.jpg




1968, Burlington bisquit No. 4



tested by the British in the mid-late 60s, the type of combined armour, at an angle of inclination of 60deg, provided protection from 6 in (152 mm) HC with penetration of 643 mm (cone angle 60, copper), and also provided protection equivalent to 136 mm steel from 120 mm APDS L15A4 ( 1300-1500 yards), the assembly weighed the same way as a 135-136mm steel plate, with an inclination angle of 68 deg the entire assembly protection was achieved from 7 and 8 in HC (penetration unknown, cone angle 40, approximately penetration something around 800 and 900- 1000 mm)


at the beginning of 1965, bisquit No. 1 was tested to provide protection against a 5-in HC; by May 65 they switched to No. 4.


the presented scheme was compiled according to a handwritten report, in which only plate thicknesses and overall assembly dimensions are exactly given, the air-gaps could be a little different if more accurate data appear, I will correct the scheme.


Edited by Wiedzmin
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I have a question about the Leyland engine installed in the Chieftain. When it was being developed the military were not very convinced about it and "asked for a conventional diesel engine from an unspecifed European country to be developed in pararell in case the L60 proved troublesome, but the Trasury refused to fund it".

 

Chieftain Main Battle Tank Manual: 1966 to Present (Owners' Workshop Manual), by Dick Taylor. J H Haynes & Co Ltd (2016), page 45.

 

Any candidates for this alternative engine? Germany could offer Leopard 1 MTU with 819 HP and the US the Continental AVDS-1790-2 with 750 HP. The issue I see is that the Chieftain's engine compartment was very tight due to smaller volume of 2 stroke engine. As a consequence large modifications would have been needed - see Shir 1 case-.

Edited by alejandro_
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Well we were supposedly designing with a common turret ring so we could utilize any American turrets that took our fancy, so it wouldnt be a stretch we were thinking of buying American engines. That might have been more preferable than buying West German, because obviously in the late 1950's, it was perhaps a little too recent.

 

I dont know what engine the AMX30 has?

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Well we were supposedly designing with a common turret ring so we could utilize any American turrets that took our fancy, so it wouldnt be a stretch we were thinking of buying American engines. That might have been more preferable than buying West German, because obviously in the late 1950's, it was perhaps a little too recent.

 

Now I need a Space-Chieftain with a M60 A2 turret. :D

 

I dont know what engine the AMX30 has?

 

Hispano-Suiza HS-110 four-stroke Diesel engine with varying horses from 680 to 720 depending on the exact version.

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Hmm, always liked the name Hispano Suiza. Was it reliable?

 

Space Chieftain, thats a thought. It was if I remember rightly the American T95 project, so I dont know whether they envisaged mounting missile turrets like the M60A2 on it or not. I always thought it was a strange thing that we wanted to swap out the strongest part of the Chieftain, the turret, and not the sodding engine.

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Hmm, always liked the name Hispano Suiza. Was it reliable?

 

Space Chieftain, thats a thought. It was if I remember rightly the American T95 project, so I dont know whether they envisaged mounting missile turrets like the M60A2 on it or not. I always thought it was a strange thing that we wanted to swap out the strongest part of the Chieftain, the turret, and not the sodding engine.

The 85" turret ring diameter became the US standard size with the M48 and as both the US and UK were simultaneously attempting to design the next generation tank, it stands to reason they would, as NATO partners, at least notionally work together. If one accepts that the tank would have a turret, the most fundamental aspect of that vehicle would be the turret ring diameter, from that everything else follows.

 

As for the powerplant, the US was, like the Brits, experimenting with engine designs such as an X-12, with one T95 even being equipped with a gas turbine. In the end the US went with a the diesel version of the tried and true AV-1790. Brits, on the other hand, always enamored with exotic engine types, stuck with the 2 stroke opposed piston six cylinder diesel. I am quite sure that the AVDS-1790 could have been fitted to the Chieftain had there been a desire to do so.

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Hmm, always liked the name Hispano Suiza. Was it reliable?

 

Space Chieftain, thats a thought. It was if I remember rightly the American T95 project, so I dont know whether they envisaged mounting missile turrets like the M60A2 on it or not. I always thought it was a strange thing that we wanted to swap out the strongest part of the Chieftain, the turret, and not the sodding engine.

The 85" turret ring diameter became the US standard size with the M48 and as both the US and UK were simultaneously attempting to design the next generation tank, it stands to reason they would, as NATO partners, at least notionally work together. If one accepts that the tank would have a turret, the most fundamental aspect of that vehicle would be the turret ring diameter, from that everything else follows.

 

As for the powerplant, the US was, like the Brits, experimenting with engine designs such as an X-12, with one T95 even being equipped with a gas turbine. In the end the US went with a the diesel version of the tried and true AV-1790. Brits, on the other hand, always enamored with exotic engine types, stuck with the 2 stroke opposed piston six cylinder diesel. I am quite sure that the AVDS-1790 could have been fitted to the Chieftain had there been a desire to do so.

 

 

It makes perfect sense we would combine knowledge and work together, particularly on things like engines, which clearly we failed to do. I just dont quite get the logic of why we would feel the need to swap a 120mm turret with what was probably at that point the best designed turret armour for a tank to date for a 152mm missile turret. We dont seem to have wanted it, or prototyped for it. It makes even less sense for us to go backward to a 105mm turret, as much of the reason to trade up from Centurion was to get a 120mm gun turret.

 

Unless the US was thinking of adopting a 120mm turret a generation earlier than they did in a MBT, but ive seen nothing that suggests that was on the cards. Perhaps there was some other gun other than the 152mm or the 120mm in the offing? Its hard to see what both sides were aiming for, when both sides were developing weapons the other side wasnt remotely interested in.

 

Yes, im sure you are right, it could have been done. And in light of subsequent events clearly should have been done. We were certainly aware of Israeli efforts to fit one in Centurion, so we presumably would have become well aware of its capabilities in the study of material we received from the Israeli's to develop Chieftains armour layout.

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Hmm, always liked the name Hispano Suiza. Was it reliable?

 

Space Chieftain, thats a thought. It was if I remember rightly the American T95 project, so I dont know whether they envisaged mounting missile turrets like the M60A2 on it or not. I always thought it was a strange thing that we wanted to swap out the strongest part of the Chieftain, the turret, and not the sodding engine.

The 85" turret ring diameter became the US standard size with the M48 and as both the US and UK were simultaneously attempting to design the next generation tank, it stands to reason they would, as NATO partners, at least notionally work together. If one accepts that the tank would have a turret, the most fundamental aspect of that vehicle would be the turret ring diameter, from that everything else follows.

 

As for the powerplant, the US was, like the Brits, experimenting with engine designs such as an X-12, with one T95 even being equipped with a gas turbine. In the end the US went with a the diesel version of the tried and true AV-1790. Brits, on the other hand, always enamored with exotic engine types, stuck with the 2 stroke opposed piston six cylinder diesel. I am quite sure that the AVDS-1790 could have been fitted to the Chieftain had there been a desire to do so.

 

 

The T-95 Pilot #1...

 

T-95_US_Pilot%201_90mm_1_1.jpg

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It makes perfect sense we would combine knowledge and work together, particularly on things like engines, which clearly we failed to do. I just dont quite get the logic of why we would feel the need to swap a 120mm turret with what was probably at that point the best designed turret armour for a tank to date for a 152mm missile turret. We dont seem to have wanted it, or prototyped for it. It makes even less sense for us to go backward to a 105mm turret, as much of the reason to trade up from Centurion was to get a 120mm gun turret.

Backward to the 105mm? Early prototype Chieftains were sporting 20 pdrs. You're assuming that the final decision to equip the new tank in the fleet with the Conqueror's 120mm was the first decision chiseled in stone? That wasn't at all the case. Guns discussed by both the Brits and the US included the smooth bore 120mm, the rifled 120mm as fitted on the M103, the 120mm as eventually equipped the Chieftain, 105mm versions rifled and smooth bore, and 90mm both rifled and smooth bore. At the time of the T95 and the beginning of the Chieftain project, a guided missile configuration was merely conceptual. I wouldn't look at the Chieftain being designed with an 85" turret ring compatible with US turrets* a resignation to regression, rather a decision to keep options open.

 

*The US was talking about turret rings conceptually as large as 136" with 78" and 110" in serious discussion for the T95/96 respectively. In the end it was determined that all the armament being seriously considered would fit within a 85" turret ring.

Edited by DKTanker
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No Chieftains had 20pdrs. You are probably thinking of 40ton Centurion that had a similar shaped turret. Even the earliest Chieftain prototype has the L11 120mm. It was a new gun, it may have been inspired by the L1 which was an American gun used in Conqueror, but it was an all new design.

 

What was the 120mm smoothbore that was under discussion?

Edited by Stuart Galbraith
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No Chieftains had 20pdrs. You are probably thinking of 40ton Centurion that had a similar shaped turret. Even the earliest Chieftain prototype has the L11 120mm. It was a new gun, it may have been inspired by the L1 which was an American gun used in Conqueror, but it was an all new design.

 

What was the 120mm smoothbore that was under discussion?

Guess I was on a roll. Perhaps I should have instead mentioned the rocket propelled 105mm ammunition being discussed or the nuclear powered turbine engine. But in any case the point remains, Brits undoubtedly went with the 85" turret ring to keep future options open. It did in fact allow the discussion, 50 years later, to perhaps fit the Challenger II with an M1A1 turret.

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Yes, they did it to keep options open, but for which side? Because as I see it, you had a 90mm gun, a 105mm gun, and a 152mm gun, none of which for various reasons we seem to have had much interest in. We already had Malkara and Swingfire under development, we didnt need another ATGM as far as I can see. The others would have been a step backwards from the L11.

 

I guess the point im trying to make is, how sure are we this was not done at the behest of the Americans to try and get a 120mm tank gun in a medium tank chassis? Because there seems to be very little, other than the 165mm demolition gun, that would be a step forward for us.

 

Ok, so part of that was down to the subsequent Vietnam war, there wasnt enough money for innovation to provide the next generation of tank guns you wanted. But what im asking is, was there some new technology gun the US was working on in the late 50's and early 60's that looked a better bet than the L11 for us? Was there a drive to get the the West Germans to have a similar ring in the Leopard 1 so we could all have a common nato standard gun? For us alone, I really dont see what we were expecting to get out of it. We would have been far better off specifying a common engine bay size.

Edited by Stuart Galbraith
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