Sir John Valentine Carden survives.

[marathag]

As far as reliability is concerned, from what I managed to find out online, Valentine was rather well off in that regard, probably because it was not: a cruiser tank, or powered by Nuffield Liberty or repurposed Bus Engines.

Before the GMC Diesels, mkI had the Gasoline AEC A189 six cylinder engine,mkII the AEC A190 diesel, Bus motors.
Not all Bus motors are bad, that GMC 4-71 and 6‐71 were successfully in that role too.
Every British Tank would have track issues until the alloy was changed in late 1941.
Now it wasn't any sort of high tech alloy, just few percent more MMolybdenum.
Could have been done any time in the 1930s, but wasn't.

 

[MattII]

Here's the thing. Yes Christie suspension has its problems however it is not bad per-se in a WW2 context. In fact in certain situations it's the best thing for the job.

Imagine if you will a Cromwell like tank armed with a 6 pound'er gun running around North Africa shooting up Italians and possibly Germans if the new speedy tanks dont over-run most of North Africa before the Germans can respond.

In fact i would say I don't care if the tank that is produced has Christie suspension, it needs to be reliable. That was the real Achilles heel of pretty much all WW2 British tanks.

Christie suspension takes up a ton of internal space, and half of it is hidden behind armour plates, so maintenance is a serious issue. There's a reason the Americans dropped it.

 

[MarcH]

Christie suspension takes up a ton of internal space, and half of it is hidden behind armour plates, so maintenance is a serious issue. There's a reason the Americans dropped it.

I know, still doesn't invalidate my argument. Yes it has it's flaws but given the number of flaws British tanks had it's hardly the worst and in the correct circumstance (charging across northern Europe or North Africa) can actually be the best option. Reliability was the major issue British tanks had, mainly to do with the engines and cooling. Yes maintenance on Christie suspension is a pain but if that's the biggest headache an early war British tanker faced he would be very happy.

Now, if given the choice I would not use Christie suspension in a tank, ever. The thing is Britain did and it is likely they will be in TTL as well. Given that, I was replying with speculation on how a Christie suspension-ed tank might perform if well designed in the early part of the war.

 

[Wet Coast]

It wasn't about members being replaced, it was about a loss of power and control. In shipbuilding at least riveters had an entirely union based training scheme, that meant it took ages to train anyone up and the supply of workers was in the control of the unions. You'd spend two years as an apprentice riveter, working on site and you still wouldn't be that quick at the end of it, it was reckoned an experienced team was anything up to 4x faster than an freshly qualified apprentice. And of course if you didn't express the correct pro-union views then you might not even qualify at all.

In contrast the employer could train a welder in a couple of months, in a classroom/workshop with no union input and the new worker would be maybe 90% as fast as an experienced welder. Of course the Unions hated that, it cut at one of the planks of their power-base, so use of welding always came with the threat of massive strikes from your existing riveters.

Maybe it was different in Vickers, but given their large shipbuilding interests I'd be amazed if the Unions weren't carefully watching the tanks side to make sure welding wasn't 'sneaking in' outside of their control.

Thanks for the information. I knew the unions had issues with welding and had heard various different rationales but nothing definitive so went with the most obvious.

 

[MattII]

I know, still doesn't invalidate my argument. Yes it has it's flaws but given the number of flaws British tanks had it's hardly the worst and in the correct circumstance (charging across northern Europe or North Africa) can actually be the best option. Reliability was the major issue British tanks had, mainly to do with the engines and cooling. Yes maintenance on Christie suspension is a pain but if that's the biggest headache an early war British tanker faced he would be very happy.

Now, if given the choice I would not use Christie suspension in a tank, ever. The thing is Britain did and it is likely they will be in TTL as well. Given that, I was replying with speculation on how a Christie suspension-ed tank might perform if well designed in the early part of the war.

Christie suspension tanks also have restricted space in the fighting compartment, which was another problem the British suffered from a lot.

 

[MarcH]

Christie suspension tanks also have restricted space in the fighting compartment, which was another problem the British suffered from a lot.

True again but that was exacerbated by the position of the gun in the Turret. Change that and you lessen the impact.

A compromised tank that works is better than an Ideal one that doesn't. Give the British a Centurion with the reliability of my old KIA it's of no use to anyone.

 

[Schlock]

Considering that Vickers used Horstmann type suspension for their tanks in this era, it's likely that Carden would have stayed with that type. Going from a pair of triple bogies to three doubles would give better weight distribution and improved redundancy as well.

Simple, robust, easy to replace and worked historically on the Centurion and Chieftain post war, so it's not like there isn't precedent.

 

[MarcH]

Considering that Vickers used Horstmann type suspension for their tanks in this era, it's likely that Carden would have stayed with that type. Going from a pair of triple bogies to three doubles would give better weight distribution and improved redundancy as well.

Simple, robust, easy to replace and worked historically on the Centurion and Chieftain post war, so it's not like there isn't precedent.

Depends on what the Army specification is. If it's Christie or no orders then it's going to be Christie.

 

[Peg Leg Pom]

True again but that was exacerbated by the position of the gun in the Turret. Change that and you lessen the impact.

A compromised tank that works is better than an Ideal one that doesn't. Give the British a Centurion with the reliability of my old KIA it's of no use to anyone.

Just confine the Liberty Engine to the dustbin of history and buy the tooling for the Kestrel from Rolls Royce. That should solve most of the reliability problems. Christy suspension may not be ideal but it works well enough and up until 1942 for the 2pdr and 1944 for the 6pdr the guns are fine.

 

[Dan]

What are the odds of ditching petrol engines entirely and switching to diesel instead?

 

[yulzari]

Just confine the Liberty Engine to the dustbin of history and buy the tooling for the Kestrel from Rolls Royce. That should solve most of the reliability problems. Christy suspension may not be ideal but it works well enough and up until 1942 for the 2pdr and 1944 for the 6pdr the guns are fine.

The tooling went off to Merlin production. If you dispense with the Peregrine the same will happen to that tooling. If you want diesels for large road vehicles then the USA is the place where that was happening. Have Bedfords make GMC diesels in the UK? It is the same company. POD being a change in UK tax and excise on lorries.

 

[Wet Coast]

What are the odds of ditching petrol engines entirely and switching to diesel instead?

One of the drivers for using gasoline instead of diesel is logistics. If your entire vehicle fleet uses the same fuel then it makes it much easier to keep your units supplied. If you have two different fuels then you effectively need a doubled (for fuel) logistical tail and you have a lot of extra coordination to ensure that the right fuel is delivered to the correct unit. Also generally speaking at the time gas engines had a better power to weight ratio, were smaller and could use more compact and lighter transmissions and cooling systems. Pretty much all nations used gas engines in their tanks at the start of the war.

 

[ArtosStark]

One of the drivers for using gasoline instead of diesel is logistics. If your entire vehicle fleet uses the same fuel then it makes it much easier to keep your units supplied. If you have two different fuels then you effectively need a doubled (for fuel) logistical tail and you have a lot of extra coordination to ensure that the right fuel is delivered to the correct unit. Also generally speaking at the time gas engines had a better power to weight ratio, were smaller and could use more compact and lighter transmissions and cooling systems. Pretty much all nations used gas engines in their tanks at the start of the war.

Valentine and Matilda were both diesel in OTL

 

[tomo pauk]

sadly, the appearance of the US Liberty, the BT-2 had a Soviet built version of that 1918 V12 engine, the M-5.
The BT-7 had the 2,864 cubic inch M-17 Radial, based off the BMW VI V12

M-17 was a V12 engine, too.

 

[Wet Coast]

Valentine and Matilda were both diesel in OTL

The original Valentine had a gas engine, it switched to diesel in the Valentine II in 1941. The Matilda used two bus engines which would have been somewhat difficult in a lighter cruiser tank but I concede the point that diesel was used. I was simply pointing out some of the drivers that pushed tanks towards gas engines rather than diesel.

 

[ArtosStark]

The original Valentine had a gas engine, it switched to diesel in the Valentine II in 1941. The Matilda used two bus engines which would have been somewhat difficult in a lighter cruiser tank but I concede the point that diesel was used. I was simply pointing out some of the drivers that pushed tanks towards gas engines rather than diesel.

True enough. Apologies for the nitpick

 

[MattII]

True again but that was exacerbated by the position of the gun in the Turret. Change that and you lessen the impact.

Only slightly, as no-one sits behind the gun anyway, they sit beside it. A narrow turret ring as needed to accommodate the Christie suspension simply doesn't allow a three man crew with a very large gun.

Christy suspension may not be ideal but it works well enough and up until 1942 for the 2pdr and 1944 for the 6pdr the guns are fine.

No they're not, neither has a decent HE round, which is a serious flaw for any tank.

 

[pjmidd]

Only slightly, as no-one sits behind the gun anyway, they sit beside it. A narrow turret ring as needed to accommodate the Christie suspension simply doesn't allow a three man crew with a very large gun.

No they're not, neither has a decent HE round, which is a serious flaw for any tank.

Ordnance 75mm QF is basically a 6pdr bored out to 75mm and fitted with a muzzle break so just use that ( basically just speed ~OTL up )

 

[MattII]

Ordnance 75mm QF is basically a 6pdr bored out to 75mm and fitted with a muzzle break so just use that ( basically just speed ~OTL up )

Yes, bored out and using American ammunition. Note that the USA was using the 75mm cannon from 1941, before they even had a decent tank.

 

[steamboy]

And the US's 75mm cannon was basically a more modern version of the French 75 from WW1 and could indeed fire the same ammunition.