thanksthe group link:Log into Facebook
Log into Facebook to start sharing and connecting with your friends, family, and people you know.www.facebook.com
the AH Saladin link:
Alternative History Armoured Fighting Vehicles Part 3
- Thread starter Claymore
- Start date
- Status
Finished reading P.M. Knight's A13 Mk I and II: A technical history (yes already read 5-6 of them in a few weeks), and this one truly is a banger when it comes to giving info on British tank development right before WW2. Beyond the A13, it indeed discusses A14 through 18, as well as A9, A10 and A11. It would be especially useful for Britbuff scenarios like John Valentine Carden survives and Munich Schuffle (or would have been).
It does a neat job of explaining how infantry and cruiser tanks were not created as a conscious move to compliment each other, but rather were the result of divergent factions existing in the British tank design departments, with men like John Davidson and Sir Hugh Elles being concerned about the power of AT guns and emphasizing heavy armor while radicals like Martel instead thought speed and inconspicuousness was more sensible as they thought AT power would always surpass armor increases. Indeed neither tank class ended up complimenting each other as they remained largely separated, and the armoured brigades equipped with Cruisers even largely ignored combined arms, something which would hurt the British for the first 2 years of war.
It does a neat job of explaining how infantry and cruiser tanks were not created as a conscious move to compliment each other, but rather were the result of divergent factions existing in the British tank design departments, with men like John Davidson and Sir Hugh Elles being concerned about the power of AT guns and emphasizing heavy armor while radicals like Martel instead thought speed and inconspicuousness was more sensible as they thought AT power would always surpass armor increases. Indeed neither tank class ended up complimenting each other as they remained largely separated, and the armoured brigades equipped with Cruisers even largely ignored combined arms, something which would hurt the British for the first 2 years of war.
In any case, one of the observations as early as the battle of France was that the need for heavier armor was vindicated, with 14mm being completely obsolete, 30mm being the bare minimum but really 40 or even 50mm was the minimum desired. In March 1937, a report had already advocated a minimum of 40mm but Martel had rejected it on the assumption that it would not be enough anyway and 60 or even 70mm would be needed to meet the expected threat. A perfectly valid assessment in the long term (armoring to meet the threat instead of incrementing by 10mm), but 40mm would still have been useful for the tanks sent to France as the German 37mm was weaker than expected and the decision of keeping 14mm (later increased to 30mm prewar) and higher speed was incorrect. As early as mid 1940 it was accepted to put the heaviest armor possible as long as a top speed of 20 mph and a power reserve for offroad driving were maintained, something which was only followed by WW2 belligerents after 1943-44 (this is also a very similar argument as the one used to design the Centurion).
Anyway, what I'm leading to in particular here is the topic of the two Vickers Cruiser tanks, A9 and A10. During 1940, it was found that due mainly to their suspension, they couldn't keep up with the faster Christie Cruisers and even wore down too quickly trying to catch up at the highest speed (A9 and A10 being both geared to achieve 40kph, although the latter was slower on average). Indeed this is the same suspension Vickers built the slow Valentine on, and knowing that A10 originally was a pseudo-infantry tank derivative of the A9, it was sensible of Vickers to double down on armor and reduce top speed to a level that was more mechanically achievable by the suspension.
In this regard, I think that a lot more value could have been extracted out of the A9/A10 if Vickers had not tried to design them for the Medium and then Cruiser role they were poorly suited for. Instead, they could have made neat intermediate infantry tanks between the Matilda II and Valentine (and a good interim to Matilda II/Valentine chronologically), as they could be armored to 40-50mm while keeping a 3-man turret (this seems possible because just such a configuration had been offered when the 2-man turret Valentine had been initially rejected). Even better, the infantry tank role meant that a hull MG or MG turrets wouldn't be required, which means that the original concept for the A9/A10 as envisionned by Carden could have been used. That is, having a sloped hull front to achieve lower weight for the same protection (the real argument at the time). A Valentine developped out of this alternate A9/A10 (the distinction wouldn't really exist) could have kept the same arrangement for slightly better performance than OTL. This setup could have been applicable to other MG-less British tanks of the time, eg A13 Mk I and II, Tetrarch and Matilda II.
TL: DR: this with gearbox set up for Infantry tank speed levels but the thickest possible armor up to 16 tons, most likely 50mm basis.
Anyway, what I'm leading to in particular here is the topic of the two Vickers Cruiser tanks, A9 and A10. During 1940, it was found that due mainly to their suspension, they couldn't keep up with the faster Christie Cruisers and even wore down too quickly trying to catch up at the highest speed (A9 and A10 being both geared to achieve 40kph, although the latter was slower on average). Indeed this is the same suspension Vickers built the slow Valentine on, and knowing that A10 originally was a pseudo-infantry tank derivative of the A9, it was sensible of Vickers to double down on armor and reduce top speed to a level that was more mechanically achievable by the suspension.
In this regard, I think that a lot more value could have been extracted out of the A9/A10 if Vickers had not tried to design them for the Medium and then Cruiser role they were poorly suited for. Instead, they could have made neat intermediate infantry tanks between the Matilda II and Valentine (and a good interim to Matilda II/Valentine chronologically), as they could be armored to 40-50mm while keeping a 3-man turret (this seems possible because just such a configuration had been offered when the 2-man turret Valentine had been initially rejected). Even better, the infantry tank role meant that a hull MG or MG turrets wouldn't be required, which means that the original concept for the A9/A10 as envisionned by Carden could have been used. That is, having a sloped hull front to achieve lower weight for the same protection (the real argument at the time). A Valentine developped out of this alternate A9/A10 (the distinction wouldn't really exist) could have kept the same arrangement for slightly better performance than OTL. This setup could have been applicable to other MG-less British tanks of the time, eg A13 Mk I and II, Tetrarch and Matilda II.
TL: DR: this with gearbox set up for Infantry tank speed levels but the thickest possible armor up to 16 tons, most likely 50mm basis.
allanpcameron
Donor
I have used these books fairly extensively in Carden Survives, and I would agree that the A10 could have been a much better tank. In fact, I would argue that your description of the A10 is what my Carden design ended up as. Because Leslie Little took over design/development he wouldn't have been quite so cavalier as Carden would have been about giving the War Office what they needed rather than what they wanted. At least I think so.
Allan
Yes, if I recall your proposal was to use A9 with A10 hull MG setup, and the original A10. My proposal would in effect kill the A9 itself, beef up your A10 and accept a lower speed and infantry role. This would definitely be a good path to your proposed Valiant since a more heavily armoured A10 would make an OTL Valentine quite redundant (maybe 10mm more armor but 2-man turret). The logical follow up for that is to upscale the powertrain and drivetrain to retain a 3-man turret but allow greater armor (in the infantry role) and address the mechanical limitations of the A10, eg your Valiant. The book also mentionned that the British had been looking at Christie (including volute spring version), Vickers Horstmann, torsion bar (studied for a bit for A16), Tetrarch setup and the "Japanese" suspension of the A12, so turns out your choice of Vickers Horstmann was valid after all (used on A14). It also mentions that an A12 armored to 30mm was proposed for the cruiser role, which makes your idea of the Cruiser Valiant also logical.
In effect, the path you took for Vickers is pretty much what Davidson and Elles would have liked, and what the War Office needed.
Last edited:
1) How hard would it be to convert unguided rockets into short range guided anti air missiles?
2) How hard would it be to convert a self-propelled unguided rocket artillery system into a self propelled guided anti aircraft missile system?
Ex: Could I put radar on a BM-21 Grad, convert the rockets into guided short range missiles, and then spam forty 122mm missiles at incoming aircraft in under 20 seconds?
2) How hard would it be to convert a self-propelled unguided rocket artillery system into a self propelled guided anti aircraft missile system?
Ex: Could I put radar on a BM-21 Grad, convert the rockets into guided short range missiles, and then spam forty 122mm missiles at incoming aircraft in under 20 seconds?
so essentially you want 122mm rockets with mistral/stinger/SA-7 heads
Yes, that can be rapid fired from preexisting (yet modified) system like a BM-21 Grad rocket launcher.
You know we have guided and self propelled artillery shells using both rocket and ramjet power right?
Randy
You want to do this in a WWII chronology?
The Germans developed automatic guidance based on optical sensors for several late war missile systems. They didn't get any of those systems working well enough to bother trying to use them. Are you proposing that the country responsible for your subject-system, if not Germany, also would do that inventing and development? Do you want it done sooner? Presumably you also want it to work pretty well. The Germans didn't come very close, and they were ahead of everyone else.
You mention radar. There was no radar technology during WWII that was sufficiently miniaturized to fit in a missile. Vacuum tube radars were big, and power hungry, and hot. And, vacuum tube computers were the same. Do you also expect to invent solid state electronics, and particularly solid state radar signal processing?
Anything can be postulated in Alternate History, but what you propose has a lot of major departures from OTL.
OTOH, if you want to do this now instead of during WWII...why? There are plenty of guided missile systems intended to down aircraft, using rockets that were designed for high speed and high G turning rather than low cost and maximum payload.
Last edited:
BM-21 Grad is a Cold War design still used today. I'm confused about the WW2 references.
No I don't know that. I'm a amateur compared to 90% of the posters on this thread.
RamscoopRaider
Donor
1) Pretty much impossible. You need to completely redesign the rocket, because instead of a small fuse in the nose you need to fit a seeker head in, and you need to include moveable control fins to actually aim it, which means you need to redesign the front of the rocket, the warhead, the fins and the rocket motor. Essentially you need to build a new missile that fits in the same launch rails as the artillery rocket. Yes the guided conversions of existing artillery rockets generally only have to redesign the front, but that is because they don't have to maneuver much, and only need to make small adjustments to fine tune their course, rather than chase a maneuvering aircraft
2) Pretty hard as the MLRS isn't meant to rapidly track targets, it's rockets are aimed slower, and they often only have limited elevations, something difficult to fix. You would also need to fit a lot of electronics, and then power generation capacity on the chassis, which depends on the chassis used as to the practicality, or use a second vehicle
For a BM-21 it really depends on the chassis whether there is room for the radar and electronics or not, a few yes, some no, most I don't know enough to say. The original Ural 375 chassis? No, maxed out in weight
AH of course is not time limited, and this particular thread has discussed AFVs from multiple periods, but it's an odd question to contemplate radically redesigning an artillery rocket system to do a complete different job, when that other job already has lots of systems in service that do it well. It wouldn't make economic- and time-sense to go to all that effort, when you could just obtain the right weapon for the job in the first place.
If OTOH you were considering whether in an AH WWII timeline something like you propose could be made to occur...well, maybe, with enough fairly radical PODs. The BM21 was just a technical descendant of prior Russian artillery rocket systems. But the general nature of some of the major PODs would result in considerably changed history, so the context of the changes might now be unrecognizable.
Are there any self propelled AA missile systems that can "spam" or "rapid fired" dozens of missiles in a small period of time?
shipmounted VLS launchers (they are technically self-propelled
)buit with guided missiles, i think a pod of 4 is the max.
remember this isn't a game in the sandbox mode, in RL guided missiles cost money - a lot of money
even a stinger missile costs 100K, and something like the SM-2 missile 20M+
The other thing about firing a cloud of missiles at the same target is the interference effect of each of the missiles trying to distinguish, not just the target from all the target's decoys, but also all the other missiles. Metal oxides in rocket exhaust can be "seen" at some microwave frequencies; obviously an infrared seeker that's behind another missile will "see" that frontward missile's exhaust plume and still-hot exhaust trail; and a visual-band or UV-band seeker would have a very hard time flying through rocket exhaust streams that might be opaque at those wavelengths.
In any case, the only way that "spamming" a large number of missiles at a given target at once would make sense is if the missiles, instead of being self-seeking and therefore all trying to follow the target, were all ground-controlled and sent toward the target in an array...so that a last-second break by the target might exceed the turn rate limitation of a missile on the target's tail, but other missiles offset in the "break" direction then could intercept it. But ground-controlled missiles are a very different design challenge than self-seeking ones.
And as noted above, that'd be a hugely expensive way to design a missile system...and you certainly wouldn't start with the low performance of artillery rockets.
In any case, the only way that "spamming" a large number of missiles at a given target at once would make sense is if the missiles, instead of being self-seeking and therefore all trying to follow the target, were all ground-controlled and sent toward the target in an array...so that a last-second break by the target might exceed the turn rate limitation of a missile on the target's tail, but other missiles offset in the "break" direction then could intercept it. But ground-controlled missiles are a very different design challenge than self-seeking ones.
And as noted above, that'd be a hugely expensive way to design a missile system...and you certainly wouldn't start with the low performance of artillery rockets.
RamscoopRaider
Donor
Yes but not in the way you are thinking
There are plenty of systems that can do it, but a system in this case would consist of multiple vehicles operating as a network unit including multiple launch vehicles, a radar vehicle or two, a command vehicle, etc. So say an air defense battalion acting as a single unit might be able to spit out 3 dozen missiles pretty fast, but using 9-12 separate launcher vehicles. Or some guided missile destroyers/cruisers but that is a different thread
The most missiles carried by any single land based vehicle is 16 missiles on the newest Russia Tor system, but it can only control 4 at a time
I'm now off to read P.M. Knight's Comet: A Technical History, and so far the first 58 pages are already a goldmine regarding the British tank programme as of 1943-44.
@MarcH You had been looking for months already for an explanation regarding the weird history of the Vickers 75mm HV, and luckily this book contains some info about that.
What is worth knowing is that based on experience with Grants and Shermans, the British had decided to study a Cromwell rearmament with the 75mm M3 or a medium velocity gun capable of shooting US 75mm ammunition for commonality. This is what led Vickers to offer what would become the OQF Mk V. At this point many officers and in particular director of artillery E.M.C Clarke wanted a gun with greater velocity to punch through heavier armor. Vickers was unofficially approached by Sir Robert Micklem (former managing director at Vickers and now in the war office/ministries) to develop a more powerful gun which would combine the HE performance of the 75 with higher hole punching capability to hopefully replace both the 6pdr and the medium velocity 75mm, to fit in the Cromwell.
While medium velocity 75mm ammo was to come entirely from the USA, the HV 75 could use American projectiles but the British would design a new HE projectile and modify US APCBC so they could manufacture HV 75mm rounds in Britain. As such, the choice of caliber most likely was not really for commonality since the ammo would be built locally anyway, but rather because Vickers was already familiar with 75mm projectiles as it had developped the medium velocity 75 first (the mounting was however delayed quite a lot). Initially only 2400 fps muzzle velocity was expected, but then this was 2750 fps in a new gun, 150 fps greater than the US 76 due to the ability to handle greater pressures, and twice the bursting charge weight. Penetration was slightly better. As such it seemed to be a great gun.
Eventually, as you know the story of "the 75 can't fit" would happen because the 75 HV lacked a semi-automatic mechanism and adding it would make it too big, so a new turret and mounting would be designed. At this point the idea of using the US 76mm M1 resurfaced (it had been considered in December 42, but at the time a new turret was not intended and since it did not fit in Cromwell it was not accepted). However, the 76 would have introduced many ergonomic and turret design difficulties that the British did not like (longer rounds so harder to load, poor compatibility with the BESA, sight and crew layout, unbalanced mounting mounted further forward which led to a King Tiger-style narrow front turret, gun can't be removed from the front, worse frontal arc protection).
However, this now led the British to compare the 75 HV with the 17pdr. It was found that the 75 HV had a more sensible and stronger tied jaw breech while the 17pdr had an open jaw breech (google, you will see what they look like). The stronger tied jaw breech meant that even accounting for the difference in raw power, the 75 HV's breech was a more compact and efficient design. Thanks to improved production capacity, the British assessed that they could now design an optimized tank version of the 17pdr which would use this style of breech and relocated mouting lugs for the recoil buffers to fit any optimized tank mounting. Although I can't confirm it, it appears this would inspire the versions of the 17pdr developped for the Sherman Firefly and Centurion. If necessary, the case of the 75 HV would be used to obtain shorter rounds.
In the meantime, it was finally chosen to adapt the 75 HV to use 17pdr projectiles because manufacturing would be simplified and it could immediately use 17pdr APCR/APDS when these rounds would become available. So there it is.
The first 58 pages of the book also feature interesting other bits on some British projects of the time. For one, since the Aussies had shown a 17pdr turret with a 64" turret ring could technically work, this was briefly studied for mounting on a suitably-modified Cromwell.
We also finally have more details on the so-called straddle-mounted Christie suspension for the A35 (35-ton Comet with heavier armor) and A36 (British Tiger: brand new 70" turret with a 17pdr, A35 hull with extra wheel station and heavier armor). This was actually a Christie suspension with outside supporting brackets: that is, a fully external version of the Christie. This was going to be used on a single skin hull (no more springs between spaced side plates), with no cross tubes to contain the shafts the axle arms were connected to, and which occupied a rather similar space as torsion bars. In turn, this meant the turret basket could be lowered and the overall profile of the tank could be improved. The A36 was quite impressive, as at just 40 tons it would carry 127mm of frontal armor basis, and 80mm-thick sides. Both A35 and A36 would be terminated along with other projects as part of a rationalization effort as a new faction emerged to support a clean sheet vehicle (Centurion) designed around the optimum armament rather than the other way around as done previously.
Personally I think it was a mistake in the end as A36 was already close to clean sheet but was evidently a significantly more weight-efficient design which eliminated the space-eating problem of the original Christie suspension (no cross tubes, external mounting) while retaining its advantages in ride quality.
Covenanter hull showing the cross tubes on the hull floor
Honestly, it is rather unfortunate that the A35-style Christie suspension arrangement was not arrived at from the start or at least much sooner. It would have completely fixed a lot of problems with Cruiser tank space use, would have simplified side armor construction and if done in a similar way as A35, would also be a sturdier design capable of handling more weight. This in turn could possibly have shortened the time necessary to develop reinforced suspensions on Crusader and Cromwell, allowing heavier designs from the start.
@MarcH You had been looking for months already for an explanation regarding the weird history of the Vickers 75mm HV, and luckily this book contains some info about that.
What is worth knowing is that based on experience with Grants and Shermans, the British had decided to study a Cromwell rearmament with the 75mm M3 or a medium velocity gun capable of shooting US 75mm ammunition for commonality. This is what led Vickers to offer what would become the OQF Mk V. At this point many officers and in particular director of artillery E.M.C Clarke wanted a gun with greater velocity to punch through heavier armor. Vickers was unofficially approached by Sir Robert Micklem (former managing director at Vickers and now in the war office/ministries) to develop a more powerful gun which would combine the HE performance of the 75 with higher hole punching capability to hopefully replace both the 6pdr and the medium velocity 75mm, to fit in the Cromwell.
While medium velocity 75mm ammo was to come entirely from the USA, the HV 75 could use American projectiles but the British would design a new HE projectile and modify US APCBC so they could manufacture HV 75mm rounds in Britain. As such, the choice of caliber most likely was not really for commonality since the ammo would be built locally anyway, but rather because Vickers was already familiar with 75mm projectiles as it had developped the medium velocity 75 first (the mounting was however delayed quite a lot). Initially only 2400 fps muzzle velocity was expected, but then this was 2750 fps in a new gun, 150 fps greater than the US 76 due to the ability to handle greater pressures, and twice the bursting charge weight. Penetration was slightly better. As such it seemed to be a great gun.
Eventually, as you know the story of "the 75 can't fit" would happen because the 75 HV lacked a semi-automatic mechanism and adding it would make it too big, so a new turret and mounting would be designed. At this point the idea of using the US 76mm M1 resurfaced (it had been considered in December 42, but at the time a new turret was not intended and since it did not fit in Cromwell it was not accepted). However, the 76 would have introduced many ergonomic and turret design difficulties that the British did not like (longer rounds so harder to load, poor compatibility with the BESA, sight and crew layout, unbalanced mounting mounted further forward which led to a King Tiger-style narrow front turret, gun can't be removed from the front, worse frontal arc protection).
However, this now led the British to compare the 75 HV with the 17pdr. It was found that the 75 HV had a more sensible and stronger tied jaw breech while the 17pdr had an open jaw breech (google, you will see what they look like). The stronger tied jaw breech meant that even accounting for the difference in raw power, the 75 HV's breech was a more compact and efficient design. Thanks to improved production capacity, the British assessed that they could now design an optimized tank version of the 17pdr which would use this style of breech and relocated mouting lugs for the recoil buffers to fit any optimized tank mounting. Although I can't confirm it, it appears this would inspire the versions of the 17pdr developped for the Sherman Firefly and Centurion. If necessary, the case of the 75 HV would be used to obtain shorter rounds.
In the meantime, it was finally chosen to adapt the 75 HV to use 17pdr projectiles because manufacturing would be simplified and it could immediately use 17pdr APCR/APDS when these rounds would become available. So there it is.
The first 58 pages of the book also feature interesting other bits on some British projects of the time. For one, since the Aussies had shown a 17pdr turret with a 64" turret ring could technically work, this was briefly studied for mounting on a suitably-modified Cromwell.
We also finally have more details on the so-called straddle-mounted Christie suspension for the A35 (35-ton Comet with heavier armor) and A36 (British Tiger: brand new 70" turret with a 17pdr, A35 hull with extra wheel station and heavier armor). This was actually a Christie suspension with outside supporting brackets: that is, a fully external version of the Christie. This was going to be used on a single skin hull (no more springs between spaced side plates), with no cross tubes to contain the shafts the axle arms were connected to, and which occupied a rather similar space as torsion bars. In turn, this meant the turret basket could be lowered and the overall profile of the tank could be improved. The A36 was quite impressive, as at just 40 tons it would carry 127mm of frontal armor basis, and 80mm-thick sides. Both A35 and A36 would be terminated along with other projects as part of a rationalization effort as a new faction emerged to support a clean sheet vehicle (Centurion) designed around the optimum armament rather than the other way around as done previously.
Personally I think it was a mistake in the end as A36 was already close to clean sheet but was evidently a significantly more weight-efficient design which eliminated the space-eating problem of the original Christie suspension (no cross tubes, external mounting) while retaining its advantages in ride quality.
Covenanter hull showing the cross tubes on the hull floor
Honestly, it is rather unfortunate that the A35-style Christie suspension arrangement was not arrived at from the start or at least much sooner. It would have completely fixed a lot of problems with Cruiser tank space use, would have simplified side armor construction and if done in a similar way as A35, would also be a sturdier design capable of handling more weight. This in turn could possibly have shortened the time necessary to develop reinforced suspensions on Crusader and Cromwell, allowing heavier designs from the start.
Last edited:
- Status