Medium

The medium tank did not appear fully formed. In the two decades following World War I, armies around the world struggled to define what such a vehicle should be, what role it should serve, and how it could be built with the technology of the day. Light tanks lacked staying power. Heavy tanks were slow, complex, and expensive. The medium tank emerged as the practical compromise-capable of sustained operations, armed to fight both fortifications and other tanks, and mobile enough to exploit breakthroughs.

Medium: Tank Development 1918-1936 explores this transitional period in depth.

Drawing on a series of technical papers and expanded research, Nelson McKeeby documents the evolution of medium tanks across multiple nations, including:

• British developments of the original tank concept
• American efforts from the M1921 and T1 series to the M2 and M3 Medium
• French interwar designs such as the Somua S35 and Char B1 bis
• German experimental programs leading to Panzerkampfwagen III and IV
• Christie's designs leading to the British Cruisers the Soviet BT series

The book examines not only vehicles, but the engineering systems that defined them: radial and V-type engines, derating and adaptation of aircraft powerplants, suspension families from leaf springs to torsion bars, evolving gun designs, armor metallurgy, sighting systems, and the introduction of tank radios and internal communications.

Equally important is doctrine. Some armies viewed the medium tank as an infantry-support machine. Others treated it as the core of fast-moving armored forces. These choices shaped turret layouts, crew size, armor distribution, and production priorities-often with lasting consequences.

Rather than presenting a single "correct" path, this volume shows how the medium tank emerged through experimentation, compromise, and industrial reality. By 1939, despite wide variation in national designs, a recognizable pattern had formed: a fully rotating turret, a medium-caliber gun, balanced armor protection, and mobility sufficient for maneuver warfare.

For readers interested in armored vehicle history, military technology, and the roots of World War II tank design, Medium: Tank Development 1918-1936 provides a detailed and grounded account of the ideas, machines, and people who shaped the modern tank.