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Author Topic: Chieftain Tank Development  (Read 18569 times)

Offline Abraham Gubler

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Chieftain Tank Development
« on: July 18, 2010, 04:31:55 pm »
Here are a few pictures of the British Army development of the Chieftan tank. The first was the original concept for the Leyland FV4201 medium tank to replace the Centurion when Conqueror production was due to end in 1957. Then there is the '40 ton Centurion' FV4202 to prove the reclined driver's position and also with a turret sans mantlet. Then of course the first Chieftan mockups which looked quite nice without all the boxes that covered it in production.
"There is a tendency in our planning to confuse the unfamiliar with the improbable." Thomas Schelling

Offline JFC Fuller

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Re: Chieftain Tank Development
« Reply #1 on: September 18, 2010, 08:15:36 am »
Does anybody have any information / details about the L11A4 105mm that was developed for the Chieftain??? Apparently it had an autoloader in an effort to reduce crew size and speed up engagement time but, perhaps inevitably, never worked.

As a side note, an external gun was considered in the early design stages for the Chieftain but never got off paper.

Offline red admiral

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Re: Chieftain Tank Development
« Reply #2 on: September 18, 2010, 08:33:27 am »
Does anybody have any information / details about the L11A4 105mm that was developed for the Chieftain???

"Cheiftain" by Rob Griffin has quite a lot of information in it, but little mention of an automatic 105mm gun. First mention is of initial design work being carried out around the US 105mm gun in the early 1950s. By the mid 1950s there was a 105mm gun with a bagged charge la 120mm L11. Some comments that the 120mm L11 would have been interchangeable with the US 90mm smoothbore on the T95.

There's also a section on AFVs in "Cold War, Hot Science" by Richard Ogorkiewicz which is very detailed, but no mention of a 105mm L11A4. There is mention of the 110mm EXP-7 which had brass cartridges and was interchangeable with the 105mm L7. Then there was a 110mm EXP-14 with semicombustible cartridges. Things moved on to the 120mm M7, then redesigned into the 120mm M13A with one piece cartridges that came a close second to the Rheinmetall 120mm L/44 in competition for arming the M-1.

External gun doesn't seem to have been for Cheiftain, but was from around the same time period for a much smaller and lighter tank - even some one-man tank designs with 2x120mm recoilless guns.

Offline JFC Fuller

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Re: Chieftain Tank Development
« Reply #3 on: September 18, 2010, 08:42:17 am »
Red Admiral,

Thank you for the reply, having double checked my notes I realise that the L11A4 was actually a 120mm (not one of my finer moments! :-[). I have a copy of Cold War Hot Science and I must say that it is an outstanding publication. Does Rob Griffin's book discuss the autoloader for the L11A4?

Thanks again.

Offline JFC Fuller

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Re: Chieftain Tank Development
« Reply #4 on: September 18, 2010, 08:56:57 am »
It would appear that the tank they used to trial the autoloader made it back into service: http://www.arrse.co.uk/rac/138682-so-ive-got-tank-l11a4-marked-gun-breech.html

Offline Old_ROF

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Re: Chieftain Tank Development
« Reply #5 on: October 22, 2010, 11:33:30 am »
To clarify the information in "Cold War, Hot science" book.

The correct designation for UK experimental ordnance took the form EXP##-M#x. The 120mm ordnance's referred to should actually be 120mm EXP19-M7 and EXP19-M13A. The latter was the UK proposal for the US XM1 MBT up against the US improved 105mm M68 and the then new GE 120mm SB.

Re: L11A4. This was a variant of the L11 breech which incorporated a different breech mechanism for the interlocks to the steel obturator seal. This was superseded by revisions to the existing design which were adopted and produced as the L11A5.

Re: Autoloaders. There was one worked on/built in the ROF in (I believe the 1960's) but this was for a 105mm L7 as it used full length cased ammunition.

Offline PMN1

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Re: Chieftain Tank Development
« Reply #6 on: November 03, 2010, 02:19:38 pm »
. Then there is the '40 ton Centurion' FV4202 to prove the reclined driver's position and also with a turret sans mantlet. T

Does anyone know if these features were possible in earlier smaller tanks?


Offline PK

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Re: Chieftain Tank Development
« Reply #7 on: November 26, 2010, 08:15:44 am »
Does anyone no any drawings for the FV4202 40ton centurion and where to get them?

Offline PMN1

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Re: Chieftain Tank Development
« Reply #8 on: January 21, 2011, 03:27:57 pm »
Does anyone know what the specs for the A45 Universal tank were to be?

Offline PK

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Re: Chieftain Tank Development
« Reply #9 on: January 28, 2011, 12:46:09 pm »
The A45 was intended to share a number of components (i,e turret tracks etc) with the A41 but with thicker armour. it was finally chosen as the basis for FV201 which turned into conqueror. There is on picture in Modern Combat Vehicles :2 by Simon Dunstan and published by Ian Allan. Good luck getting an inexpensive copy of the book as they don`t come cheap. The same picture (there may be som elsewhere) is also available in the Squadron Signal book Centurion in action.   
  There may well be a more comprehensive description in the Conqueror book published by Crowwood which is fairly easy too come by.
 Sorry , not much but I hope it helps.
 

Offline PMN1

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Re: Chieftain Tank Development
« Reply #10 on: February 22, 2011, 12:23:04 pm »
I'm reading the New Vanguard book on the Centurion and its says that fundamental to the Universal Tank design, was the ability to adapt it to specialised roles and it was thought the Centurion could not be adapted to do so.

What was it about the Centurion that made the General Staffs think this and what was it about the Universal Tank design FV200 series that would have made it adaptable?

Offline xiaofan

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Re: Chieftain Tank Development
« Reply #11 on: February 24, 2011, 11:02:32 pm »
Found this photo on flickr by emdjt42

"This is the prototype Chieftain with a 1000hp engine, whose development was not carried forward, and was donated to the Yorkshire Air Museum by Vickers Defence Industries, and is seen there on October 5th 2008."

 

Offline JFC Fuller

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Re: Chieftain Tank Development
« Reply #12 on: February 24, 2011, 11:58:23 pm »

Offline PMN1

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Re: Chieftain Tank Development
« Reply #13 on: February 26, 2011, 04:09:11 am »
Why develop a 1,000hp Chieftain when you already have a 1,200hp engine in the Shir 1 (Khalid)?

Offline Sea Skimmer

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Re: Chieftain Tank Development
« Reply #14 on: March 24, 2011, 01:27:12 am »
Low cost, these would be the third rate last ditch reserve tanks, plus standardization with certain foreign units. The 1000hp engine fitted was basically the same German engine being used for a German M48 upgraded program which was expected to spread to other NATO states. It was also used in several other European armored vehicles, I think Italy used it for tanks and SPHs. This however was all taking place around 1990 and you know what happened next. Not much needed to be developed, both engine and transmission existed and other then that all you need are different mounting bolts and a wiring harness.