Search Results for: KRV

Memo regarding Centurion turrets on the Krv chassis

A memo dated 1959-06-12 regarding the possibility of putting a Centurion mk 10 turret on the Krv chassis. Some modifications are required of either the chassis itself or the turret, and a turret blueprint with some handwritten notes on it is attached.

Archive reference: SE/KrA/0266/002/01:H/F I/32

Report (May 1958) from the 2nd Equipment Planning Study Group

Original title: Rapport maj 1958 från studiegrupp 2 för fortsatt tygmaterielplanering

The 2nd study group for further equipment planning was responsible for figuring out what kind of requirements would be reasonable to expect from next-generation direct-fire AFV’s (tanks and APC’s, mostly) that were to enter service around 1965. In order to do this, the group considered what the Soviets were doing, what everyone else was doing, current bleeding edge research, where tank development was right now and where it was heading. In May of 1958 the group issued this report, which is a bit over 90 pages long.

The report discusses current trends in tank development, and designates three general lines of development called the A-tank, the T-tank and the S-tank.

  • The A-tank (A for America, probably) is the expected result from current US and UK design philosophy. It weighs about 40-45 metric tons and is frontally protected against sub-caliber kinetic penetrators fired from guns of up to 120 mm caliber, with mobility somewhat impaired by its weight. (In reality, this alternative later resulted in the M60 Patton and the Chieftain.)
  • The T-tank (T for Tyskland – Germany) is the expected result from current German and French design philosophy. It weighs about 30-35 metric tons and has very high specific engine power (25-30 hp/t or more), but only has frontal protection against (the equivalent of) 57 mm guns. (In reality, this alternative later resulted the Leopard 1 and the AMX-30.)
  • The S-tank (S for Sweden) is a proposed turretless Swedish design that has the same protection as the A-tank against kinetic weapons, while weighing only about 30 metric tons. Additionally, since the gun is fixed in the chassis, it can be fitted with screens or lattices that will protect it from all currently known anti-tank missiles and other HEAT penetrators.

The report then goes on to reason about the importance of low tank weight with regards to strategic mobility. For Swedish conditions, tanks should ideally weigh less than 37 metric tons. Based on this and other factors, the authors argue that the army should not purchase upgunned Centurions from the UK, as they are too heavy and an insufficient upgrade over the 84 mm variant. Instead, it is recommended that future Swedish tank development should focus on a) testing the S-tank concept in practice to see if it’s a workable solution, b) start development on a domestic A-tank equivalent (reusing the existing Krv chassis for experiments as necessary), using an autoloader instead of a manual loader to keep the weight down, and c) keep an eye on developments in the US and UK with the intention of purchasing complete tanks if something better/cheaper than the domestic alternatives comes up.

The report also features about a metric ton of appendices, which I have photographed but not published here because they are mainly used as support for the recommendations outlined in the main report and thus not really all that interesting on their own. If you see one you want in the table of contents, leave a comment and ask for it and I’ll post it.

Archive reference: SE/KrA/0266/002/01:H/F III/1

Memo regarding considerations for series production of akv 151 (KV 155)

Original title: PM rörande akv 151, överarbetning av konstruktionen med hänsyn till planerad tillverkning i serie

This memo (dated 1960-01-04) discusses series production of the akv 151 SPG (aka. KV 155, the bkan 1 prototype) and some of the project history. The author notes that since the original suggestion in the second quarter of 1949, eleven years have passed and series production has not yet started. A number of reasons for this is mentioned (lack of engineers, changes in the specification, doubts whether the project is viable at all). The author concludes that because of the changes in the specification and the fact that the current prototype is based on a chassis (the Krv) that is not likely to be mass produced, the vehicle (and its chassis in particular) will need to be reworked before it can enter series production.

The author also mentions that it would be desirable to reduce the weight of the vehicle; the prototype weighs 45 metric tons but according to a 1958 report Swedish AFV’s should weigh no more than 37 metric tons, and if possible weigh less than 25 tons. A note in the margin exclaims “-18% !” in red next to this paragraph; someone who read the memo probably doubts that this is possible (and they would be right, because the series production version turned out to weigh 52 metric tons in the end).

Finally, four alternatives are presented; two conventional and two using the suspension to help with gun elevation. The weight for all four alternatives is claimed to be less than 37 tons, which seems like a pipe dream in retrospect. Rough drawings of the alternatives are attached.

Archive reference: SE/KrA/0266/002/01:H/F I/43

Memo regarding the future development of turreted tanks (1959)

A memo dated 1959-03-23, outlining the guidelines for future development of turreted tanks. The “A-tank” (the conventional turreted alternative to the S-tank, developed in case the hydraulic gun laying system on the S-tank would prove unworkable) is put on hold (and thus effectively cancelled, since the army ended up choosing the S-tank) and possibilities for putting a Centurion mk 10 turret on the Krv chassis is discussed. The latter is proposed as an alternative to purchasing the Centurion mk 10 mainly for economical and trade balance reasons, since it would mean building the tank in Sweden rather than purchasing it from the UK.

Archive reference: SE/KrA/0266/002/01:H/F I/32

Memo regarding the procurement status of SPG, SPAAG and tanks

Original title: PM ang. akv, lvkv och strv enligt tygmaterielplan 1958/66

A memo from the Vehicle Bureau dated 1958-05-02, discussing the procurement status of current SPG’s, SPAAG’s and tanks (well, one of each, really). The SPG (akv 151) is built on a Krv chassis but now it seems like the Krv project will be cancelled, which is problematic. The Krv project itself is likely to get cancelled because of problems with the ammunition; options for keeping it alive is simply purchasing a new gun plus ammunition for it off-the-shelf abroad. There are two SPAAG alternatives; one is to purchase a “Grantham” SPAAG off-the-shelf, the other is doing something with the indigenous lvkv fm/49 (aka. lvkv 42).

Archive reference: SE/KrA/0266/002/01:H/F I/19

Project EMIL: a summary

This is a report of the then-current status of the EMIL project (also known as krv, kranvagn, project 6400, etc), dated 1952-10-15. Over the course of some hundred pages or so (although not all of the original pages seem to be in the archive I found it in) it covers in great detail what a tank like EMIL needs to do and why it needs to do it.

Archive reference: SE/KrA/0266/002/01:H/F I/19
Note that this report was originally classified top secret (“of great importance for the security of the realm”); the reason it’s in an archive volume dated 1958 is because its classification status was reduced to “regular secret” at that point; top secret and regular secret archives are kept separately.

Meetings at Bofors in late 1954 regarding status of current projects

Minutes from two meetings at Bofors (on 1954-09-22 and 1954-12-08) discussing the status of various projects. More specifically:

  • Kv 155 (SPG; later became akv 151, even later bkan 1)
  • Project 6400 (heavy tank, aka. KRV)
  • FH 105 X (105 mm towed field howitzer)
  • Obusier de 155 mm Modèle 50 (popularly called “Haubits F” or “Fransyskan”; a towed French howitzer license produced by Bofors)
  • FAK 120 X 53 (a towed 120 mm automatic AA gun; considered by the meeting attendants to be of doubtful value)
  • Lvkv fm/49 (a SPAAG)
  • “Light brigade AAA”; unspecified 20 or 30 mm towed AA gun
  • 75 mm L/60 gun for strv 74
  • “Gjallarhorn”, speculative man-portable light anti-tank weapon

Archive reference: SE/KrA/0266/002/01:H/F I/1

Orientation regarding current projects (may 1954)

Minutes from a meeting (1954-05-04) at the arms administration’s vehicle bureau regarding the status of current projects. Mentions the “tankette” (project 6400 aka. the KRV), kv 155 (a SPG prototype that would eventually become akv 151 and then eventually bkan 1), lvkv fm/49 (a SPAAG) and the upgunning of strv m/42.

Archive reference: SE/KrA/0266/002/01:H/F I/1