The Gundlach Periscope, usually known under its British designation as Vickers Tank Periscope MK.IV, was a revolutionary invention by Polish engineer

Rudolf Gundlach Rudolf Gundlach (1892–1957) was a Polish military engineer, inventor and tank designer. He headed the design division of the Armored Weapons Technical Research Bureau (''Biuro Badań Technicznych Broni Pancernych''). He held the military rank ...

, manufactured for Polish

7TP The 7TP (''siedmiotonowy polski'' - 7-tonne Polish) was a Polish light tank of the Second World War. It was developed from the British Vickers 6-ton. A standard tank of the Polish Army during the 1939 Invasion of Poland, its production did not e ...

tanks from the end of 1935 and patented in 1936 as the ''Peryskop obrotowy Gundlacha''. It was the first device to allow the

tank A tank is an armoured fighting vehicle intended as a primary offensive weapon in front-line ground combat. Tank designs are a balance of heavy firepower, strong armour, and good battlefield mobility provided by tracks and a powerful engi ...

commander to have a 360-degree view from his

turret Turret may refer to: * Turret (architecture), a small tower that projects above the wall of a building * Gun turret, a mechanism of a projectile-firing weapon * Objective turret, an indexable holder of multiple lenses in an optical microscope * Mi ...

with a single periscope. By rotating the periscope and allowing the tank commander to look backwards through the second eyepiece, he no longer had to change position to look behind the turret. Early tanks had small turrets and fixed seating, without an independently rotating cupola, and so the commander wasn't easily able to move himself to another rear-facing periscope. On 14 June 1935 it was officially adopted by the

Polish Army The Land Forces () are the land forces of the Polish Armed Forces. They currently contain some 62,000 active personnel and form many components of the European Union and NATO deployments around the world. Poland's recorded military history stre ...

, as reversible periscope G wz. 34. The design was first used in the

TKS The TK (TK-3) and TKS were Polish tankettes developed during the 1930s and used in the Second World War. Design and development The TK (also known as the TK-3) tankette was a Polish design produced from 1931 based on the chassis of the British ...

tankette, then in

light tank. Shortly before the war it was given to the

British British may refer to: Peoples, culture, and language * British people, nationals or natives of the United Kingdom, British Overseas Territories, and Crown Dependencies. ** Britishness, the British identity and common culture * British English, ...

and was used in almost all tanks of

WWII World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

, including the British Crusader,

Churchill Sir Winston Leonard Spencer Churchill (30 November 187424 January 1965) was a British statesman, soldier, and writer who served as Prime Minister of the United Kingdom twice, from 1940 to 1945 during the Second World War, and again from 1 ...

, Valentine, and

Cromwell Oliver Cromwell (25 April 15993 September 1658) was an English politician and military officer who is widely regarded as one of the most important statesmen in English history. He came to prominence during the 1639 to 1651 Wars of the Three Ki ...

and the American

M4 Sherman } The M4 Sherman, officially Medium Tank, M4, was the most widely used medium tank by the United States and Western Allies in World War II. The M4 Sherman proved to be reliable, relatively cheap to produce, and available in great numbers. It ...

. After the German and Soviet attack and fall of Poland in 1939 it was copied entirely from captured 7TP and TKS Polish tanks and later used by the

Soviets Soviet people ( rus, сове́тский наро́д, r=sovyétsky naród), or citizens of the USSR ( rus, гра́ждане СССР, grázhdanye SSSR), was an umbrella demonym for the population of the Soviet Union. Nationality policy in ...

for their tanks (including the

T-34 The T-34 is a Soviet medium tank introduced in 1940. When introduced its 76.2 mm (3 in) tank gun was less powerful than its contemporaries while its 60-degree sloped armour provided good protection against anti-tank weapons. The C ...

and

T-70 The T-70 was a light tank used by the Red Army during World War II, replacing both the T-60 scout tank for reconnaissance and the T-50 light infantry tank for infantry support. The T-80 light tank was a more advanced version of the T-70 with ...

). As a part of Polish-British pre-war military cooperation, the patent was sold for one zloty to

Vickers-Armstrong Vickers-Armstrongs Limited was a British engineering conglomerate formed by the merger of the assets of Vickers Limited and Sir W G Armstrong Whitworth & Company in 1927. The majority of the company was nationalised in the 1960s and 1970s, w ...

. It was produced as the Vickers Tank Periscope MK.IV (pictured), and built into all British tanks (Crusader, Churchill, Valentine, Cromwell). After the fall of Poland, Germany, USSR and Romania captured some equipment, allowing them to copy the invention. In USSR the Gundlach periscope was known as MK-4 (harking to the British designation, as Russian sources openly confirm that it was copied from samples acquired with British-supplied tanks) and implemented in all tanks (including the T-34 and T-70). At the end of World War II this technology was adopted throughout the world and used basically unchanged for almost 50 years, until it was replaced by electronic devices.

References

{{Reflist *Grzegorz Łukomski and Rafał E. Stolarski, ''Nie tylko Enigma... Mjr Rudolf Gundlach (1892-1957) i jego wynalazek'' (Not Only Enigma... Major Rudolf Gundlach (1892-1957) and His Invention), Warsaw-London, 1999.
1938 US patent 2130006 "periscope for armored vehicles"
Armoured fighting vehicle vision and sighting equipment History of the tank Military equipment of Poland Polish inventions