Friday, 1 January 2016

Unneeded Scout

The PzII n.A., more commonly known as Luchs, had a competitor developed by BMM (formerly CKD), the Pz38(t) n.A. It was superior in, at the very least, reliability and armament, but the Luchs entered mass production instead. Why did this happen, and what was the light tank developed in occupied Czechoslovakia like?

Supply and demand

The performance of the PzII Ausf. D tank in the Polish Campaign made it clear that the Wehrmacht needs a new light tank. In the middle of September of 1939, even before the fighting was done, the Ministry of Armament and Ammunition sent out an order for a new fast reconnaissance tank.

At first, MAN and Daimler-Benz worked on the project together: the first company was developing the chassis, the second the the turret and turret platform. The project was indexed VK 13.01 (experimental vehicle, 13 ton class, first prototype). It would reach a speed of 70 kph, have a two man turret, armour up to 30 mm, and weigh 11 tons.

New Competitors

In July of 1940, the situation changed. Two competitors emerged that MAN and Daimler-Benz did not think of. In March of 1939, Germany occupied Czechoslovakia and took control of their manufacturing base, including Skoda and Českomoravská Kolben-Daněk (CKD), the chief producers of Czechoslovak armoured vehicles. After the occupation, the factories continued making tanks for their new masters. The factories retained their design bureaus and continued to design new tanks.

BMM finished their scout tank in December of 1941, almost 6 months after MAN (the PzII n.A. was finished in July of 1941), but the headstart was annulled by changes to the requirements. Several major changes were made in 1941 alone, and the grandiose plans of 250 VK 13.03 tanks and lighter VK 9.03 tanks had to be corrected. MAN did not begin production in the fall or winter of 1941. Production of the PzIII was also hampering MAN, and demand for them was at its peak. This played right into the hands of the Czech companies, which caught up to their competitors.

Differences from the old model

The BMM project was first called TNH n.A. (neuer Art, new type), and was not designed from scratch. The design team used their experience in designing the TNH (better known as LT vz 38 or Pz38(t)) extensively. The overall layout and a significant part of the hull migrated to the new design. The engine was in the rear, transmission and drive wheels at the front. At the same time, the tank was anything but a cosmetically altered Pz38(t).

The design bureau didn't waste their two years of development, and the requirements called for serious changes. The 220 hp Praha NR1 V-shaped 8 cylinder engine was chosen for the TNH n.A. The new engine was longer than the old Praha TNHPS/II (a licensed copy of the Swedish Scania-Vabis typ 1664), so the engine compartment had to be enlarged. The suspension looked similar, but looks can be deceiving. The tank was almost a ton heavier, so it too had to be changed. The diameter of the road wheels grew from 775 to 810 mm, and the tracks were widened from 293 to 305 mm. The drive wheel changed too.

Significant changes were made to the hull. Aside from lengthening it, the front was redesigned. The hull machinegun was removed, replaced with a vision block for the radio operator, similar to the one on the PzIII. The driver received the same vision block. The tank's armament consisted of a 37 mm Skoda A-19 gun and a coaxial MG-34. The tank had no commander's cupola, but had a large bump with observation devices on the perimeter.

Special features

It's worth mentioning the technology for the hull and turret of the TNH n.A. Almost all Skoda and BMM vehicles had riveted hulls and turrets. This design has many drawbacks, including secondary fragments caused by rivets flying off when the tank was hit. The TNH n.A. was the first tank at BMM that was fully welded. According to sources, the first tank was riveted and made from mild steel, the second was welded from mild steel, the third was riveted from hardened steel, and the remaining two were welded from hardened steel. According to the plan, BMM produced one prototype per month. The last tank was produced in April of 1942. It's worth noting that no prototype was entirely welded, as the rear and engine compartment doors were still riveted.

The prototypes differed in other ways. The first one had track covers from the Pz38(t). The tank did not receive observation devices, and they were replaced by screens with snow wipers. The tank was equipped with two Notek lights and an automotive horn on the right side of the front plate. The second prototype, with a welded hull and turret, got new track covers. The third prototype was closer to the first one, but received new track covers and a floodlight on the roof. Later, a Tatra Typ 103 220 hp diesel engine was installed on this tank. Like the first prototype, the third received no observation devices. The tank finally reached its final shape with the fourth and fifth prototypes, which received a full set of optics.

Trials and unfair competition

The first vehicle went through a majority of the trials. In late January of 1942, it was shipped to Kummersdorf where it underwent trials alongside the PzII n.A. and the Skoda T-15. Over a few months, the prototype travelled 3866 km without significant breakdowns, which compared favourably to its competitors. It would appear that the Czech tank was winning, but everything was decided during the second stage of the trials in May-June of 1942. The Pz38(t) n.A. and T-15 lost points for having lower clearance and higher fuel consumption. Additionally, the 37 mm gun ate up precious turret room, whereas the PzII n.A. had a more compact 20 mm gun.

The notes in the report suggest that MAN used their administrative powers, especially regarding armament. The author had to know that the 20 mm gun was already unsatisfactory for the German military in March of 1942. In spring of 1942, requirements were made that the PzII n.A. (Pz.Spw.Wg. II Ausf. MAN) had to have a two man turret with a 50 mm gun. This requirement refers to the turret from the VK 16.02, otherwise known as the Gefechts Aufklärer Leopard. Specifications for the Pz.Spw.Wg. II Ausf. BMM were right next to the Pz.Spw.Wg. II Ausf. MAN specifications, and also feature a 50 mm gun in a Daimler-Benz turret. Overlaying the turret over the BMM design shows that this conversion would have been possible. Either way, nothing more than letters and sketches was done on this subject.

The PzII Luchs achieved a Pyrrhic victory. MAN was so full of orders that only 100 of these tanks were produced. If BMM received an order for its Pz38(t) n.A., the situation might have been different. Nevertheless, the experience of designing the tank was not wasted, and the modernized suspension was used for the Jagdpanzer 38(t) tank destroyer.

The prototypes had various fates. The third prototype served as an experimental testbed for the Tatra Typ 103 engine and solutions planned for the TNH-57-900 tank. The final fate of the other tanks is unknown, but at least one tank survived the war. Judging by the track covers, it's the second or third prototype, but the picture quality is so poor that one cannot tell if the tank is riveted or welded.

Original article by Yuri Pasholok.

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