Author: Sp15 Silentstalker: Hello everyone, today, I have a guest article from you from player sp15 (US forums), dedicated to Swedish heavy tank development. Enjoy! Sp15: Recently about 90 pages of information on the Krv project was found by EU and NA player Renhaxue. I’ve myself been working closely with him and I thought we might as well share the information we have now that we have the archived documents. So without further ado let’s start. After World War Two, Sweden’s tank force had quickly become outdated, the most advanced tank in service was the Strv m/42 which was the equivalent of an early model Sherman, and it was clear that something better was needed. So in 1949, Sweden did set requirements for a new heavy tank. It seems this project was a response to the development of western heavy tanks by the Americans and British and like their heavy tank projects, the main goal was to counter the threat of the Soviet IS-3. AKV “1949″ SPG We don’t know exactly how this first 1949 version looked like, but there is a schematic for a SPG based on the Krv, or rather Project EMIL from 1949 (since Krv Aka Kranvagn (“Crane vehicle”) was the cover name for the prototype hull). Project EMIL, 1951 Then there is a gap in the knowledge of the project until 1951. We have full documentation on the project including schematics from that time. An interesting thing to note is that the hull appears to be largely unchanged from the 1949 SPG. At this point the projected vehicle was a frontally heavily armoured but still mobile, weighing 28 tonnes, at this point the only armament was a 12cm rifled gun meant to fire heat ammo with a stabilized warhead, although there were plans for a subcaliber shell. Here are the full stats and the schematics for the 1951 version: Combat weight: 28 ton Length total: 7,4m Length excluding gun: 5,8m Width: 2,6m Height excluding aa-machine gun: 2,35m Track width: 0,55m Ground clearance: 0,4m Crew: 3 Armament: 12cm Autocannon, L/40 Engine:SFA 8 cyl Engine output: 550hp Power to weight ratio 19,5 hp/t Armour: Turret: front 150mm at 45° Sides, front 125mm at 80° Sides, rear 30mm at 90° Roof, 18mm at 0° Hull: front, UFP 70mm at 22° LFP 125mm at 38° Sides 20mm at 90° Roof, front, 30mm at 0°, rear 18mm at 0° Rear 30mm at 90° Floor; front 40mm at 0°, rear 15mm at 0° The next info that we have on the project comes from a 1952 report, by this time it is determined the project should move on and the 15cm smoothbore gun has been chosen as the main alternative for the project with the ability to mount a rifled 10,5cm gun in the same turret as a backup. There is a lot of talk about possible engines for the project all of which are air cooled American ones ranging from 500 to 810hp and based on which of these engines and which weight limits were to be used, 3 options for the tank are presented. For these, different armour values are discussed for frontal armor (hull lower: 120mm ,hull upper: 75mm, turret front: 140mm) or (hull lower: 145mm, hull upper: 95mm, turret front: 170mm) and side armour (turret/hull) (40/20),(60/30) or (80/40), although the heaviest combination of armour is only deemed viable on alternative 3. Alt EMIL 1 Armed with a 12cm gun and using the 500hp engine, this tank can be reduced in size from the preferred alt 2. This option corresponds with the original draft, it would weigh 29.5-33 tonnes with little to no upgrade potential for the armour. 33,3 tonnes Length: 6,40m Width: 2,84m Height: 2,46m Crew: 3 hp/t: 15,1 Max speed: 48kph Ground pressure: 1,10kg/cm^2 ground clearance: 0.4m Track width: 0,6m Road wheels: 6 engine:AOS-195 (500hp) armament: 12cm L/40 fire rate: 30rpm Ammo capacity: 28 magazine load: 14 elevation/depression: +8/-12 Armour turret:(140/40/20) Armour hull: (120/20/18) Alt EMIL 2 Armed with a 15cm gun and with 10.5cm as an alternative, using a 540hp or a 665hp engine if possible. Side and frontal armour is upgradeable with the more powerful engine, this is the most realistic and preferred version with a weight of max 38 tonnes. 38 tonnes Length: 6,40m Width: 3,00m Height: 2,56m Crew: 3 hp/t: 18,1 Max speed: 56kph Ground pressure: 1,20kg/cm^2 ground clearance: 0.4m Track width: 0,62m Road wheels: 6 (there were drafts with 8) engine: AV-1195: (540hp), AVS-1195 (665-668hp) armament: 15cm L/40, 10.5cm L/67 fire rate: 30rpm Ammo capacity: 24 magazine load:12 elevation/depression: +8/-12 Armour (turret):(170/60/30) Armour (hull): (145/30/18) Alt EMIL 3 Armament same as alt 2, only possible with the 810hp engine, therefore it’s considered somewhat unrealistic. This alternative, while bigger than the first two, has potential to mount the heaviest armour and still reach the weight of only 42 tonnes with a power to weight ratio of around 19hp/t 42 tonnes Length: 6,75m Width: 3,05m Height: 2,66m Crew: 3 hp/t: 19,5 Max speed: 60kph Ground pressure: 1,20kg/cm^2 ground clearance: 0.4m Track width: 0,62m Road wheels: 6 (there were drafts with 8) engine: AV-1790 (810hp) armament: 15cm L/40, 10.5cm L/67 fire rate: 30rpm Ammo capacity: 24 magazine load:12 elevation/depression: +8/-12 Armour (turret):(170/80/30) Armour (hull): (145/40/18) Im sad to say we don’t actually have the schematics for these proposals (other than the 1951 version) that should have been in the documents, but the Swedish archive system isn’t very good, at least when it comes to these kinds of things… Anyhow, the next info we have is from 1955 where there is some concern over the development of the ammunition for the 15cm gun, the 810hp engine has also been procured for study and it provides the base for a Swedish developed engine. The Swedish engine is able to produce a maximum of 723hp and it is what would have been mounted on the Krv. A prototype chassis is also under construction at Landsverk. Meanwhile, Bofors is asked to reduce the turret armour to (side 70mm)(rear 30mm)(roof 22mm)(bottom 18mm), if necessary for stabilization. Requirements are also made to increase the possible elevation to +10 degrees, which increases the turret weight by 2 tonnes to 17 tonnes. This and other changes makes the tank reach the final weight of 45 tonnes. Mock up of the 45 tonne Krv The “Kranvagn” hull with a dummy turret Next information we have is from 1958, by this point it is clear that the development of the ammunition for the 15cm gun is a complete failure and that the 10,5cm gun isn’t powerful enough. There is serious doubt whether the project should continue and French and English options for armament is discussed, allegedly Continue reading →

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