3.7-cm PaK 35/36 (PanzerAbwehrKanone 35/36)

The Wehrmacht PAK 35/36 anti-tank cannon made its presence felt in the early invasion campaigns, ultimately outdone by the increasing thickness of Allied tank armor.

The 3.7-cm PaK 35/36 ("PaK" for "PanzerAbwehrKanone") was the standard-issue anti-tank cannon of the Wehrmacht by the time of the German invasions of 1939. Like other German systems in development during the 1930's the PaK 35/36 was field tested in the Spanish Civil War to good effect. The PaK 35/36 proved the importance of crew-served anti-tank weapon systems during the early campaigns. By 1940, however, with progressively thicker armor appearing on British, French and Russian tanks, the PaK 35/36 was quickly falling out of favor as a frontline tank killer.

The PaK 35/36 was a light battlefield weapon easily maneuvered by its crew into most any firing position. Its relatively small size also allowed for easier concealment by anti-tank crews, an advantage when ambushing unsuspecting enemy vehicles. The main force of the PaK 35/36 was its potent 37mm L/45 barrel nestled in an angled armored shield straddled on either side by two road wheels and anchored by two split-trail tubular legs. Wheels were initially of the spoked wheel-type for improved horse traction as the German Army was still relying heavily on pack animal-towed artillery. It was not until 1934 that a steel wheel with pneumatic tire version suitable for vehicle towing entered production. The crew of three remained relatively exposed - save for the shield and any other natural protection - when loading and firing the weapon.

Ammunition types ran the gamut of armor piercing, high velocity, high explosive and hollow charge type projectiles. Elevation was limited to -5 t +25 with a traverse of 60 degrees. Muzzle velocity was a reported 2,500 feet for armor piercing rounds and 3,400 feet for HVAP and APCR projectiles. The effective range was about 2,000 feet (other sources report a much lower effective range).

On the West Front, the PaK 35/36 excelled most excellently against the lightly armored vehicles in the Spanish Civil War and proved equally potent against the Polish defense forces years later. The weapons peak would soon come when facing off with the heavy British Matilda II and French Char B1 tanks - projectiles ricocheting off their thick armor. On the East Front, the PaK 35/36 was still in frontline service in 1940 despite its official replacement by the 5cm PaK 38 series. It still proved effective against the Russian BT-7 and T-26 series of tanks but the arrival of the stout T-34 series (and even the lumbering KW-1 and KW-2 models) rendered the PaK 35/36 approach wholly obsolete. Its ineffectiveness garnered the PaK 35/36 the adequate nickname of "Heeresanklopfgerat", translating to "army door-knocker".

Attempts were made to shore up the ineffectiveness of the PaK system by introducing a new projectile type into the mix - the armor-piercing "Panzergranate 40" featuring a wolfram core. Unfortunately in practice, the new round failed to provide the added punch and so an even newer projectile was devised - the "Stielgranate 41" - this with a hollow charge and stabilizing tail plane. Fielded in 1942 with the PaK 35/36, this new projectile was of some benefit though the low muzzle velocity of the PaK 35/36 barrel itself meant that the crew needed to be some distance closer to the enemy tank target than was comfortable.

As a whole, production of the PaK 35/36 was stopped from 1942 onwards though by sheer surplus the weapon was fielded in quantity while other larger caliber weapons were being designed and put into production. The PaK 35/36 did prove useful in an auxiliary role, specifically when mounted on mobile platforms such as the SdKfz 250 and SdKfz 251 half-tracks (when fielded in the light anti-armor support role). Thanks to the weapon system's portability, Fallschirmjager ("parachute") were also issued this anti-tank cannon along with garrison and training units. At any rate, the PaK 35/36 secured its legacy by introducing many-a-nation to a proven anti-tank weapon from which to design their own versions from.

14,459 PaK 35/36 systems were reportedly produced beginning 1928. Development by the Rheinmetall company of a dedicated anti-tank cannon - eventually to become the PaK 35/36 - for the German Army began as early as 1925.