I haven't found an appropriate thread where to put some interesting rare stuff related to WW2 development, be it industrial one or makeshift field modifications.
Let's start with two things. The first one is a relatively recently found rarity from Swedish archives - a drawing of ČKD/BMM V8H-Sv tank. The drawing and a letter was found by WoT enthusiasts in Swedish archives in 2014 (the original announcement and the drawing source is here). The drawing is from a message dated 8th September 1941. One of the reasons why this drawing was not known before may be that the Czech archives were partially destroyed by floods in 2002. Anyway it is an export modification of the V-8-H tank accepted into Czechoslovak service as ST vz.39 but never produced due to the cancelation of all orders after Münich 1938 (for the same reason negotiations about licence production in Britain failed). Also later attempt to sell the tank to Romania failed due to BMM being fully busy with Wehrmacht priority orders. The negotiations with Sweden about licence production of V8H-Sv lasted till 1942, at least in May 1942 Swedish commission was present in Prague for negotiations. The tank differed compared to the base ST vz.39 in thicker armor with different front hull shape (armor 60 mm @ 30° on the hull front and also 60 mm on the turret; all sides were 40 mm thick). The tank was heavier (20 tons) and had the LT vz.38 style suspension with probably even larger wheels. The engine was still the same Praga NR V8 (240-250 Hp per source). The armament was unchanged with 47 mm Škoda A11 gun and two vz.37 HMG. The commander's cupola was of the simple small rotating type similar to those used on AH-IV-Sv tankettes. It is known that the Swedes officially asked to arm the tank with 75 mm gun, replace the engine with Volvo V12 and adding third HMG to the back of the turret. In the end the Swedes decided to prefer their own Strv/m42.
Source of the drawing
The second is makeshift field modification found on Balkans. It appears Ustasha forces (and possibly some SS anti-partizan units) used several Italian M15/42 medium tanks with turrets from Pz.38(t). There are several photos of such hybrids but little more is known. On one photo it is possible to see Ustasha registration number U.O. 139.
Few more photos of such hybrid.
It appears that the source of all those photos to be found on the internet is this book, Armoured units of the Axis forces in southeastern Europe in WW2 by Dinko Predoevic.
The Al Khalid derived from Norinco Type 90IIM MBT. It was in the early 90s, when India started to test their Arjun MBT. Pakistanis looked for a MBT design that could be produced by herself.
Norinco provided their own Type 90IIM prototype, this is an MBT design which comprised many Western components, such as engine and transmission.
There were 4 prototypes for Al-Khalid development, namely P1, P2, P3 and P4.
P1 has a Chinese tank diesel engine with ZF LSG3000 transmission.
P2 has a British Perkins CV12 Condor diesel engine with French SESM ESM500 transmission.
P3 has a Ukrainian KMDB 6TD-2 2-cycle boxer engine with its own twin planetary gearbox.
P4 has a German MB871 engine with ZF LSG3000 transmission, similar to South Korean K1 MBT.
Norinco and Pakistanis planned to adopt one of the Western powerpack at first, but due to CoCom (Coordinating Committee for Export to Communist Countries) restrictions, China is under embargo, which means China would not import weapons form Western countries. Obviously P3 powerplant would be the only choice. All those descriptions on the internet about ESM500 in Al-Khalid is fatally wrong.
The Al-Khalid pre-production batch and production version all equipped with Ukrainian KMDB 6TD-2 powerpack.
It is an extremely compact design, the engine laid transversely in engine room, twin planetary gearboxes connect to both left and right end. The 6TD-2 has two crankshafts: the front one drives the mechanical supercharger, while the rear one drives the gearboxes. The cooling system covering the whole engine room, the engine itself has no mechanical connection to the cooling system, and the cooling system doesn't need mechanical drive. The cooling system based on a unique principle: exhaust gas driven ejector. The exhaust gas from the engine is injected through the outlet ducting, produce a low pressure in the outlet side, that will suck in cold air from the inlet side. This principle is also used in the T-64, T-80UD and T-84, but as far as I know, Swedish Ikv 91 is the only western tank that have similar cooling principle.
As a result, the total length of powerpack is significantly shortened, much more shorter than the European powerpack mentioned above. This leads to a spare storage room between the fighting compartment and the engine compartment. This storage is for extra ammunition and fuel, when turret points 3 or 9 o'clock, the top cover of the storage could be opened from outside, containing 10 rounds for main gun, with projectiles on the outsides, semi-combustible charges on the inside.
The data table from HIT also describe the ammunition capacity as 39+10, means that 22 ready rounds in the T-72 type carousel autoloader, 17 backup rounds scatter around the fighting compartment, and extra 10 rounds could be carried in the storage room.
The driver of Al-Khalid control the vehicle via steering wheel and an automatic gear control box. The steering wheel and gear control box send electrical signals to the computer, then computer control the hydraulic servo actuator to perform engage and disengage of brakes and clutches, making steering and gear changes, as well as adjusting the speed and torque of the engine.
Mechanically the gearboxes are nearly the same as T-64s and T-72s, but have different side reducer unit. The KMDB side reducer unit is designed as a secondary gearbox, acting like a forward-reverse selector. When both reducers were put into reverse, the vehicle can reverse using the normal forward ranges. From 1st gear to 4th gear, all could be used as high speed reverse, and that's why KMDB said this is a 7F4R gearbox system. And if only one reducer was put into reverse, the track will be driving in opposites direction, causing the vehicle turns within its tracks, a.k.a. pivot steer or center steer. T-84 also applied this driving and steering system.
The advantages of Al-Khalid's powerpack is the versatility: all 3 types of MBT in the Pakistanis arsenal, T-80UD, T-84, Al-Khalid, share the same engine and gearbox.
By phasers on stun
Fellow fish - imagine you had some money to develop the "next generation" 20-40mm" modular architecture turret. Of course, you could talk about sensor fusion, using AI to detect threats, better / more integrated sensors... targetting linked to drones etc... But is this the way forwards. ?
What is the SOTA 30mm turret on the market ? - more importantly, what are it's attributes ?? [ no need to name the manufacturer unless you want to]
Built in APS ?
intelligent Armour ?
Self Repair ?
We all have ideas... what would you see as a truly game changing set of characteristics ?
I think the T2000 looks interesting and there are some nice turrets from lower profile companies (as seen at AUSA).
Alternatively, we might be at the end of the roadmap - "gun + armour + sight is good enough"
Anti-air bobcat design to take away driver's hearing in maximum efficiency
SH11 155mm SPG