I think if you do a rewrite there's a couple concepts worth exploring. The Chieftain was initially supposed to be replaced by the MBT80 of which there are a few concepts and prototypes floating around, the Challenger was a low cost replacement based off the Shir 2 for Iran so I'd like to see a TL where it comes to fruition. Also the Jaguar concept you created was cool but maybe pursue the BAe P.110 and have Britain go it alone, grease some palms so the Saudis buy and fund it to make it easier financially. Being that it resembles a twin-engine Gripen the design should lend itself better to navalization so you maintain CATOBAR capability and have a single fighter for both the RN and RAF.
A series of assumptions: a Britwank on a budget?
- Thread starter Riain
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Another good idea would be to replace the Chieftans engine in the later marks after its apparent that it won't ever be sufficiently reliable
But....but.....but what about the Chieftain scream?
Seriously though Chieftain can be easily fixed with 2 things
1: Tell NATO to fuck right off with the multi fuel bollox - it was never used and reeks of good idea fairy to me
2: Actually purchase enough spare engines - the whole intention of the design was to have an engine that could be replaced very quickly in the field (like inside of 1 hour) so that the tank crews could rag the fuck out of it (as had been the case in combat for the previous 20 years that the British and everyone else for that matter) and replace the engine often and allow the removed engines to be worked on in a workshop while keeping the tank in the field. This concept fails when on average each tank has, hang on, carry the 3, divide by the square root, oh yeah, zero spare engines, because of penny pinching treasury twats! Which meant that when the engine did pack up there was no spare engines to replace it meaning that a large % of Chieftains at any given time where U/S simply for want of a spare power pack.
Riain
Banned
@Have Blue-117 @Spencersj345.346 @Cryhavoc101 The Chieftain is a good idea, it's my favourite 60s tank and not going along with NATO because it doesn't suit Britain lines up well with not going balls deep with NBMR 3 & 4 because the RAF already has stuff going on.
However will simply stating diesel as the fuel make a decent engine? If they still go with the L60 will the Mk1-4 have 485hp, the initial/pre-production Mk4A 585hp and definitive production Mk4A2 650hp? Or perhaps will it start further along the development path with prototypes having 585hp, initial/pre-production 650hp and definitive production 720hp and go from there?
I've read that with so little power the drivers had to really 'work' the gearbox which tended to shit itself as a result, but as the engine power slowly increased this became less of a requirement and lasted that bit longer. I've also read that the Vickers MBT used the same L60 and transmission without nearly as much trouble because it was so much lighter.
Of course the overriding principle is that Britain can only make 1 good decision, either be design or fluke. If Britain decides to go diesel not multi-fuel, she cannot also chose a better engine than the L60 to work with. Similarly if Britain chooses a better engine than the L60 she is stuck with multi-fuel until the idea was abandoned. BTW was multi-fuel abandoned, I thought the Leopard 1 could use almost anything?
However will simply stating diesel as the fuel make a decent engine? If they still go with the L60 will the Mk1-4 have 485hp, the initial/pre-production Mk4A 585hp and definitive production Mk4A2 650hp? Or perhaps will it start further along the development path with prototypes having 585hp, initial/pre-production 650hp and definitive production 720hp and go from there?
I've read that with so little power the drivers had to really 'work' the gearbox which tended to shit itself as a result, but as the engine power slowly increased this became less of a requirement and lasted that bit longer. I've also read that the Vickers MBT used the same L60 and transmission without nearly as much trouble because it was so much lighter.
Of course the overriding principle is that Britain can only make 1 good decision, either be design or fluke. If Britain decides to go diesel not multi-fuel, she cannot also chose a better engine than the L60 to work with. Similarly if Britain chooses a better engine than the L60 she is stuck with multi-fuel until the idea was abandoned. BTW was multi-fuel abandoned, I thought the Leopard 1 could use almost anything?
AIUI the L60 was chosen in part because it could do multi fuel. The original choice was an RR diesel V8. The requirement for multi fuel changes the spec. So not going multi fuel will likely get you a different engine as a matter of course.
The Chieftain originally was going to have a RR V8 Diesel engine before the multifuel decision was 'inflicted' on it late into the design process
So given Rolls Royce's Pedigree in its and Rovers V12 Meteor Engine based on the Merlin I suspect that the V8 would have been a better engine than the L60
The other option is to use the same US AVDS 1790 as the M60 and Merkava I through III used?
My understanding was that only the L60 and a US heavy Truck engine actually entered service with the requirement but I just google fu'd and yes the Leo 1 Power Pack is listed as multi fuel so maybe use a version of that engine?
Well if need be you could steal the engine the US used in their T95FV4021 prototype...and yes that was a thing
Riain
Banned
I'm doing a bit of reading and I'm not sure sure about replacing the L60.
Does anyone know what V8 RR was going to use? The only ones I could find were the petrol 18L Meteorite in the Antar with 285hp in the early 50s and the 18 litre inline 8 C series with 330hp of the early 60s. Also the early Chieftains, when the RR V8 was selected, were to weigh 40 tons and the FV4202 was the vehicle built in early 1956 based on Centurion components used to test the reclining driver's position intended for FV4201. It was also referred to as the '40-ton Centurion'.
The multi-fuel policy came out in 1957 the Rolls-Royce engine an unsuitable option and so a new engine with this capability was required. Leyland Motors was asked to develop an opposed-piston two-stroke diesel of similar design to those previously produced by Napier and Tilling-Stevens, the latter's Commer TS3 engine being particularly highly regarded. This configuration, apart from being well-suited to multi-fuel use, also had the advantages of being of simple design with a low parts count, had low bearing loads, and possessed good cold-starting characteristics. The use of the two-stroke cycle allowed for a greater power for a given displacement, the 19 litres of the projected diesel engine being expected to be capable of around the same power as the previous, larger displacement, 27 litre, 600 hp Rover Meteor petrol engine.
As for the Chieftain, it was supposed to weigh 40 tons and I think the 1956 prototype weighed close to that but by 1959 changes meant that it had increased in weight to almost 50 tons. Would the 1954 RR V8 be able to handle this increase in weight, or does the more modern 2-stroke L60 need to be developed from 1957 no matter what?
Does anyone know what V8 RR was going to use? The only ones I could find were the petrol 18L Meteorite in the Antar with 285hp in the early 50s and the 18 litre inline 8 C series with 330hp of the early 60s. Also the early Chieftains, when the RR V8 was selected, were to weigh 40 tons and the FV4202 was the vehicle built in early 1956 based on Centurion components used to test the reclining driver's position intended for FV4201. It was also referred to as the '40-ton Centurion'.
The multi-fuel policy came out in 1957 the Rolls-Royce engine an unsuitable option and so a new engine with this capability was required. Leyland Motors was asked to develop an opposed-piston two-stroke diesel of similar design to those previously produced by Napier and Tilling-Stevens, the latter's Commer TS3 engine being particularly highly regarded. This configuration, apart from being well-suited to multi-fuel use, also had the advantages of being of simple design with a low parts count, had low bearing loads, and possessed good cold-starting characteristics. The use of the two-stroke cycle allowed for a greater power for a given displacement, the 19 litres of the projected diesel engine being expected to be capable of around the same power as the previous, larger displacement, 27 litre, 600 hp Rover Meteor petrol engine.
As for the Chieftain, it was supposed to weigh 40 tons and I think the 1956 prototype weighed close to that but by 1959 changes meant that it had increased in weight to almost 50 tons. Would the 1954 RR V8 be able to handle this increase in weight, or does the more modern 2-stroke L60 need to be developed from 1957 no matter what?
Riain
Banned
It looks like the RR V8 was all new.
.....the original design work took the form of a water-cooled V-8 four-cycle [four-stroke] engine of 1,460 cubic inches swept volume (23.9L) which was designed for production in either a spark-ignition or compression-ignition form. It was developed by the Rover Company, which for many years had been responsible for the Meteor V-12 gasoline engines of the British Centurion and Conquerer tanks. It was exhibited in mock-up form at the British Fighting Vehicle Research and Development Establishment in 1956 but it was never put into production, either in its diesel of gasoline form.
Therefore it's a simple decision, don't design the L60 because the RR V8 is already developed and the April 1957 defence cuts means they can save the money.
EDIT: I'm thinking how much power the 24 Litre RR V8 would make.
.....the original design work took the form of a water-cooled V-8 four-cycle [four-stroke] engine of 1,460 cubic inches swept volume (23.9L) which was designed for production in either a spark-ignition or compression-ignition form. It was developed by the Rover Company, which for many years had been responsible for the Meteor V-12 gasoline engines of the British Centurion and Conquerer tanks. It was exhibited in mock-up form at the British Fighting Vehicle Research and Development Establishment in 1956 but it was never put into production, either in its diesel of gasoline form.
Therefore it's a simple decision, don't design the L60 because the RR V8 is already developed and the April 1957 defence cuts means they can save the money.
EDIT: I'm thinking how much power the 24 Litre RR V8 would make.
- 19 litre L60 made 650hp in 1965 and 720 in 1971,
- 29 litre HS-110 made 720hp
- 37 litre MB838 made 830hp
- 29 litre AV1790 made 750hp
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My copy of Jane's Main Battle Tanks (Second Edition) says that the Iranian Army was considering the possibility of refitting its complete Chieftain fleet with the Rolls Royce CV12 diesel, developing 800hp (against the 1,200hp of the Shir 1, Shir 2) and a re-engined Chieftain (Chieftain 800) was shown at the 1980 British Army Equipment Exhibition.
The book also mentions the prototypes of the Chieftain 900 that appeared in 1982 and were so called because they had CV12 engines that developed 900hp.
I'm guessing that the CV12 wasn't available early enough for the British Army's Chieftains to be built with this engine. However, was it available in the second half of the 1970s? Would it have been an improvement on refitting the Chieftains with L60 Mk 8A engines? If the engine was available and if it was an improvement would it have been more expensive than refitting them with the L60 Mk 8A engine?
Edit
The entry on the Khalid tank say that Iran ordered 125 Shir 1 and 1,225 Shir 2 in December 1974 and that the first three Shir 1 prototypes were completed in January 1977. It goes onto say that by that time production of the Shir 1 was well under way at Royal Ordnance Leeds with the first production tanks scheduled for delivery in 1980. All of these tanks had the 1,200hp version of the CV12 engine.
The completion of the Shir 1 prototypes in January 1977 makes me think that refitting the British Chieftains with the 800hp version in the second half of the 1970s was possible. Am I right?
The book also mentions the prototypes of the Chieftain 900 that appeared in 1982 and were so called because they had CV12 engines that developed 900hp.
I'm guessing that the CV12 wasn't available early enough for the British Army's Chieftains to be built with this engine. However, was it available in the second half of the 1970s? Would it have been an improvement on refitting the Chieftains with L60 Mk 8A engines? If the engine was available and if it was an improvement would it have been more expensive than refitting them with the L60 Mk 8A engine?
Edit
The entry on the Khalid tank say that Iran ordered 125 Shir 1 and 1,225 Shir 2 in December 1974 and that the first three Shir 1 prototypes were completed in January 1977. It goes onto say that by that time production of the Shir 1 was well under way at Royal Ordnance Leeds with the first production tanks scheduled for delivery in 1980. All of these tanks had the 1,200hp version of the CV12 engine.
The completion of the Shir 1 prototypes in January 1977 makes me think that refitting the British Chieftains with the 800hp version in the second half of the 1970s was possible. Am I right?
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The Canadian brigade was part of BAOR from 1951 to 1971. Had it not been moved the logistical problems that @Bougnas mentions would apply to the Leopard instead of the Chieftain.
My copy of Jane's Main Battle Tanks (Second Edition) doesn't say when Canada ordered its Leopard 1s. However, it does say that the total value of the Canadian order, for 114 MBTs, six bridgelayers and 8 ARVs, was C$187 million, of which C$115 million was for the vehicles, C$2.7 million for the loan of 35 Leopards until the Canadian Leopards were ready and the remaining C$69.3 million for logistics supplies, ammunition and other equipment. The first Leopard 1A3s, called C1 by the Canadians, were handed over in June 1978.
Therefore, is it possible that the Canadian Chieftains would be fitted with the CV12 engine in its 800hp or 1,200hp form regardless of whatever the British did with their Chieftains in the second half of the 1970s? An important argument against the Canadians fitting their tanks with a different engine is less standardisation, which would be the main reason for buying Chieftain in the first place. That is provided the 4th Canadian Infantry Brigade wasn't moved to the south of Germany.
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Vickers also developed a 1000 HP prototype of the Chieftain using a German engine and Gearbox in the 80s to retrofit the Kuwaiti Chieftains
However before the refits could be rolled out Saddam invaded and the upgrades never happened and as a result this one off was the most powerful Chieftain ever built
However before the refits could be rolled out Saddam invaded and the upgrades never happened and as a result this one off was the most powerful Chieftain ever built
Is Victor a typo for Vulcans?
You did mention the Victor in Post 527, but wrote that 31 Mk 1s were converted to tankers instead of 30 and that No. 215 Squadron was "canned" in 1977 instead of No. 214 Squadron was disbanded in 1977.
FWIW I'd forgotten about the Hercules and Vulcan tanker conversions, which was why they weren't mentioned in Post 524.
(The last No. 215 Squadron was a transport squadron equipped with AW Argossies. It was formed on 1st May 1963 at RAF Benson and moved to RAF Changi the following August, where it remained until it was disbanded on 31st December 1968. Source: RAFWEB)
I also consider the Chieftain the overall best tank design with steel armor and manual loaders (my hypothetical ideal WW2-era tank has more elements from the Chieftain than any other tank).
I made a post on another thread about the L60, and the problem seems to be that it is an opposed-piston engine. I had found some other threads on the Internet that indicated as such:
Those were taken from this site.
Those were taken from this site.
This seems to be why such opposed-piston engines weren't used in ground vehicles that much. The original designs all stem from the Junkers Mo3 (which is described along with its entire engine family here), which was eventually developed into the Jumo 204 family of aircraft engines. They were developed into the Jumo 223 and 224 aircraft engines (detailed here). Meanwhile Napier had licensed the Jumo 204 and 205 as the Napier Culverin and Cutlass, but built very few, and eventually developed the Napier Deltic (detailed here) along the same general lines of the Jumo 223. This seems to have inspired the Leyland L60 and the RR K60 engine used in the FV430 series, as well as the 5TDF family used in Soviet tanks (more on this below). But the earlier Junkers and Napier engines were used in aircraft, boats, and locomotives, where they were connected to either propellers or generators which mostly ran at a constant speed and variable load- the Leyland L60 as mentioned was also used as a generator. At the variable speeds and loads of tanks and ground vehicles it seems the opposed-piston engines were less suitable.
The Soviets also used studies of the Jumo engines to develop a tank engine at the request of Alexander Morozov (the most influential tank designer in the USSR). It was multi-fuel, though the main purpose of the design was to allow an engine layout that made the engine compartment far smaller than other tanks. The engine was used in the T-64 family and had problems just like the L60. The problems and work to solve them are covered in great detail on this page, so that may give some insights into the problems of the L60.
However unlike the T-64, the Chieftain was apparently over its design weight to start with, and most improvements in engine power after that were canceled out by the introduction of Stillbrew armor in the 1980's which increased weight further.
Riain
Banned
The RR V8 seems too good to be true.
Given it was ready in mock-up for by 1956 whereas the L60 didn't start design until 1957 as the WP came out looking for 100 million in savings it's a simple matter of saving money first and meeting NATO policy with the next vehicle.
As a conventional design it looks like it would avoid the teething troubles of the L60's horizontally opposed layout, with seals and the like, so would be as reliable as tank engines of the 60s get. Also it likely would have made its designed initial power early enough to uncover the shortfalls with the TN12 transmission in the prototype testing phase.
The production V8 would likely have made the required ~720hp from initial batch so the Chieftain would not spend its life desperately trying to play catch up in terms of engine power and reliability which hurt its sales prospects. I doubt there would be any need for the CV12 in the 70s if the V8 was specified in 1957 as it would have development potential to exploit rather than reliability and power shortfalls to fix.
However does that mean that Leyland needs to be compensated for not getting the tank engine? RR built the K60 horizontally opposed 6cyl multi-fuel used in the FV432 as far back as 1955, can it build both tank V8 and K60?
Given it was ready in mock-up for by 1956 whereas the L60 didn't start design until 1957 as the WP came out looking for 100 million in savings it's a simple matter of saving money first and meeting NATO policy with the next vehicle.
As a conventional design it looks like it would avoid the teething troubles of the L60's horizontally opposed layout, with seals and the like, so would be as reliable as tank engines of the 60s get. Also it likely would have made its designed initial power early enough to uncover the shortfalls with the TN12 transmission in the prototype testing phase.
The production V8 would likely have made the required ~720hp from initial batch so the Chieftain would not spend its life desperately trying to play catch up in terms of engine power and reliability which hurt its sales prospects. I doubt there would be any need for the CV12 in the 70s if the V8 was specified in 1957 as it would have development potential to exploit rather than reliability and power shortfalls to fix.
However does that mean that Leyland needs to be compensated for not getting the tank engine? RR built the K60 horizontally opposed 6cyl multi-fuel used in the FV432 as far back as 1955, can it build both tank V8 and K60?
Does anyone know how many Chieftains were actually manufactured? I’ve had trouble sorting between new builds and (possibly factory) upgrade packages that may basically be factory rebuilds. My estimate is almost 2,000.
I posted the quote because it made me think that Trudeau would buy Leopard 1 tanks regardless of the merits of the Chieftain ITTL. Instead he has to be a close personal friend of the British Prime Minister, who was Harold Wilson until 5th April 1976 when he was succeeded by James Callaghan.