I’m sure some of you are familiar with this vehicle – the Cromwell. Officially designated as
Tank, Cruiser, Mk VIII, the Cromwell combined good mobility with a decent gun and reasonable armour.
But it was designed back in 1942 and by the end of the war it’s fair to say it was showing its age.
So you may be shocked to discover that there was a variant of the Cromwell still serving in 1993.
In this video I’m going to discuss what I like to call the Super Cromwells – the
Challenger, Avenger, and Charioteer. To discover what on earth possessed the
British engineers to create these vehicles, we must travel back to the Second World War,
and more specifically, the North African campaign, where British tanks were struggling against their
German counterparts in the wide open plains of the Sahara. The Brits 2 pounder guns,
their most common tank armament of the time, was pretty much useless and had been for a while. More
capable guns were on the way, with the British 6 pounder and the American 75mm starting to appear.
However the British designers weren’t stupid, and they knew that soon enough the enemy would
start fielding more heavily armoured tanks and they would need a bigger gun to deal with them.
This gun was developed as fast as possible, and would become the 17 pounder,
one of the best anti-tank weapons of the entire war. But this was a towed AT gun and the
British wanted to be able to mount it in a tank. Multiple ideas were put forward – like mounting
the gun on the aging crusader, the failed Vickers vanguard assault tank, or in the M4 Sherman.
All of these were rejected. Instead, the gun would be mounted on the valentine hull as the “Archer”,
the M10 hull as the “Achilles” and on the Cromwell hull as the A30 “Challenger”.
The Cromwell hull, if they could make it work, was ideal. Cromwell used the Rolls
Royce Meteor engine and was a relatively light tank. This combination made it fast,
with early models capable of 64 km/h before it was modified to make it slower as going that
fast was wearing the vehicles out. Having a 17 pounder armed tank with that sort of mobility
would be a major boost for the Brits. Mounting it on the Cromwell chassis, which was going to
be in production anyway, also served to reduce cost and development time. A perfect solution.
Almost immediately, the designers realised that a new turret was required,
as the Cromwell turret was nowhere near large enough. The 17 pounder was a big gun,
but it also had big recoil – after firing a round the entire gun would move up to a metre backwards,
so space was needed behind the breech. On top of this, the British wanted the new
turret to hold 4 crew members, the commander, a gunner, and 2 loaders for the massive shells
that the 17 pounder fired. To hold 4 men and a 17 pdr gun the new turret was big and boxy.
The very front armour was 102mm thick, with the cheeks being 63mm and angled backwards
at 40 degrees. The sides and rear were 40mm, and the top was 20. This meant the Challenger
had slightly more armour than the Cromwell, offering protection similar to the M4 Sherman.
This new turret was huge, but more importantly, it was heavy – an extra 6 tons compared to Cromwell.
This meant, to have similar ground pressure, the hull would need to be lengthened so an
extra road wheel could be added on each side, spreading out the extra weight. The hull machine
position was also removed, providing more space to store ammunition for the main gun.
The first prototype was ready in August 1942.
Challenger had gone from drawing board to prototype in under 8 months,
which is an insane achievement. But, perhaps as a result, the vehicle was extremely flawed,
and even the improved 2nd prototype presented in January 1943 wasn’t up to scratch.
It was at this point the British stopped and had a think. Was the Challenger really necessary?
The 6 pounder gun and the American 75mm were enough to tackle even the Panzer 4.
They’d been expecting much more heavily armoured German vehicles by this point in the war.
But, as they were poised to cancel Challenger, reports came in of a new German tank – the Tiger I.
The introduction of the Tiger caused chaos in British tank design offices.
They needed a vehicle that could destroy it, and they needed it ASAP.
But it was fine - Vickers had been working on a high velocity 75mm gun that would do the job,
but somehow, they only discovered very late on that this gun would not fit in the Cromwell
as planned, and a new turret would need to be designed for this gun as well. The Challenger,
like it or not, was their best option, and 200 Challengers were ordered in February 1943.
But British tank production at that point in the war was slow. D-Day was looming, and the
British were desperate, so they revisited an old idea of sticking 17 pounders into M4 Shermans.
A gang of rogue engineers had been working on the problem for months, and the ministry of supply
begrudgingly accepted that this may actually be a good idea. This design would become the iconic
Sherman Firefly, which was a stop gap for the A30 Challenger, which itself was a stop gap for the
A34 Comet. It was all a bit of a mess.
So. They’d pulled it off - the British would have two 17 pdr equipped tanks by D-Day. There
is a narrative sometimes that the Firefly was a good tank, and the Challenger was a bad one. This
wasn’t really the case. Yes, Challenger had a tall turret when compared to Cromwell, but it was still
10 inches shorter than the Firefly. It didn’t have sloped frontal armour like the Firefly, but had
double the gun depression, enjoying 10 degrees of depression while the Firefly only had 5. It
was just as fast as the Cromwell, making it significantly more mobile than the Sherman,
and also had a higher rate of fire due to the extra loader. The Challenger and the Firefly
were deployed interchangeably, with a typical tank troop having 3 75mm armed vehicles, and one
17 pdr. 3 Cromwells and 1 Challenger, for example. The reason for all this Firefly propaganda may be
that the Challenger couldn’t actually participate in D-Day. It had no deep wading capability,
so had to wait until ports could be captured or mulberry harbours could be built to be deployed
in Normandy. It did see service from July 1944 onwards however, and performed well,
many crews preferring it to the Firefly. However only 200 were ever built, with the
A34 Comet poised to enter service and the Sherman Firefly proving a capable substitute until then.
The Royal Armoured Corps had been responsible for the Challenger, as it was a tank.
Tank destroyers fell under the jurisdiction of the Royal Artillery, and they,
being stuck with the Archer and Achilles for their 17 pounder needs, wanted a more capable vehicle.
This program would result in the A30SP Avenger. The Avenger took a
lot of inspiration from the Challenger. It too was a modified Cromwell mounting a 17
pounder in a new turret. But the approach was different. Armour was not as important for a
tank destroyer. The emphasis this time was on visibility for the crew and a low silhouette.
As a result, the Avenger’s turret was significantly shorter than Challengers. The top of
the turret was open with a metal cover and canvas flaps to protect the crew from the elements.
The mostly open top made it significantly easier for the crew to see out of the vehicle,
and gave them more space to work in. The hull was also lower, giving the
entire vehicle a much smaller profile.
Like the Challenger, the Avenger had a lengthened hull to incorporate another road wheel.
It was planned that Britain would order around 500 of these vehicles, but only 80 were ordered
and much less were produced by the time the war ended. Avengers built during the war used the
Cromwell hull as planned, but post-war avenger vehicles used the Comet hull, easily spotted by
the presence of return rollers above the tracks. The vehicle remained in trials until 1950, when
it became clear that the Comet and Centurion were superior vehicles with the same firepower.
After all it was the 1950s, you couldn’t get away with slapping a huge gun into a tank designed in 1942.
Or could you...?
Early Centurions were armed with the 17pdr. By the time the Mark III Centurion entered service,
it had a new gun, the 20 pdr, which was far superior. But the British were making 20
pounder guns much faster than they could make Mark 3 Centurions to put them in.
The FV214 Conqueror was meant to be the primary anti-tank threat of the
British army against a potential soviet invasion, but it was still in development.
And so, once again, British tank designers turned to the Cromwell for help. The 20 pounder
offered more power than the 17 pounder but was significantly more compact. This meant that
it could be mounted on a relatively unmodified Cromwell hull, and didn’t require any lengthening
or extra roadwheels. They welded a big plate over the hull machine gun, widened the turret
ring and called it a day. This did mean that the weight of the turret was severely constrained,
and as a result the vehicle’s turret armour was thin, with all round protection being only 30mm.
The new vehicle, in service from 1952, would be known as the FV4101 Charioteer,
and 442 would be built, more than Challenger and Avenger combined.
The Charioteer was better than nothing, but not much better. The 20 pounder gun would struggle
if the Soviets did decide to invade, with questionable performance against the new T-54.
The gun was soon replaced on the Centurion by the 105mm L7, which made the Charioteer obsolete.
Some went to the Territorial Army back in Britain and many were exported abroad,
with Austria, Finland, Jordan, Lebanon and Palestine all using the vehicle at some point.
Many of these Lebanese vehicles fell into the hands of paramilitary groups, and some were
reportedly used until 1993 as I mentioned earlier.
Challenger, Avenger and Charioteer were 3 attempts to do the same thing, with mixed results.
But it’s an interesting story. Maybe they’ll put
a laser on the Cromwell hull next. Or a railgun or a cruise missile or something.
As always, thanks for watching. And thank you SO much for 5,000 subscribers!
That is such a huge milestone and I'm so happy about it :)
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