Hispano Mk II

Hispano Mk II
Name	Hispano Mk II
Origin	Spain
Type	autocannon
Service	1930s–1950s
Used by	Spain, France, United Kingdom, Germany
Wars	Spanish Civil War, World War II
Designer	Dámaso Berenguer
Design date	early 1930s
Manufacturer	Hispano-Suiza, Bofors, Mauser
Produced	1932–1948
Weight	60 kg (gun only)
Length	2.1 m
Cartridge	20×110mm Hispano
Caliber	20 mm
Action	gas-operated
Rate	750 rounds/min
Velocity	850 m/s
Feed	60-round drum

Hispano Mk II

The Hispano Mk II is a 20 mm autocannon developed in Spain in the early 1930s and widely adopted for aircraft, armored vehicles, and naval mounts. Originating from designs at Hispano-Suiza and refined amid interwar rearmament, it saw service in the Spanish Civil War and later in World War II where it was mounted on fighters and bombers fielded by nations including France, the United Kingdom, and Germany. The weapon influenced subsequent autocannon families and was adapted by firms such as Mauser and Bofors.

Design and Development

The Hispano Mk II emerged from collaborative engineering at Hispano-Suiza and workshops linked to Spanish naval arsenals, drawing on earlier experiments with 20 mm concepts pioneered by designers associated with Dámaso Berenguer and engineers influenced by developments in France and Sweden. Early trials referenced mechanisms used by Vickers and refinements popularized by Oerlikon designs, resulting in a gas-operated, single-barrel autocannon capable of integration into fighters derived from airframes like the Messerschmitt Bf 109-class and indigenous types influenced by Heinkel and Fairey. Political pressures from the Second Spanish Republic and later the Francoist Spain regime accelerated adaptation for both fixed and flexible mounts, while export negotiations involved companies such as Bofors and licensing talks with Mauser.

Technical Specifications

The Mk II used the 20×110mm Hispano cartridge and a gas-operated action with a firing rate around 700–800 rounds per minute; muzzle velocity averaged near 850 m/s similar to contemporaneous autocannon used by Hawker Hurricane and Supermarine Spitfire installations. Weights and dimensions allowed installation in wing roots, fuselage bays, and turreted mounts on aircraft like those built by Savoia-Marchetti and Junkers. Ammunition feed options included 60-round drum magazines and linked belts adapted from Browning-type feed systems; barrel length and chamber dimensions were comparable to cannons fielded by Fiat and Sikorsky-equipped platforms. Sights and harmonization procedures often referenced standards employed by air arms of the Royal Air Force and Armée de l'Air.

Operational History

The Hispano Mk II first saw combat during the Spanish Civil War mounted on indigenous fighters and bombers, and captured examples entered inventories of factions and foreign volunteers associated with units like the Condor Legion and international brigades. During World War II the cannon equipped aircraft and coastal vessels operated by France prior to 1940, and later by German forces after occupation, paralleling deployments of weaponry in theaters involving the Battle of Britain, Mediterranean campaigns around Malta, and North African operations alongside matériel from Fiat and Breda. Postwar, surplus Mk II systems appeared in export stocks to Latin American air arms and were retrofitted into armored cars and light naval craft built by firms such as Vickers-Armstrongs and Navantia successors.

Variants and Modifications

Several variants adapted the core design for specific roles: fixed wing installations with synchronized firing gear for propeller clearance mirrored systems used on Bristol Blenheim and Gloster Gladiator mounts; hydraulically cooled naval adaptations paralleled developments at Bofors for shipboard autocannon; and shortened-barrel ground-attack versions resembled modifications made by Mauser and Spanish arsenals to suit armored reconnaissance vehicles. Hybrid conversions combined Hispano Mk II actions with magazine and belt feeds akin to those on MG 151 and Oerlikon 20 mm patterns. Experimental remote-controlled turrets and powered mounts reflected trends from firms like Norden and Vickers.

Production and Manufacturers

Primary production was undertaken by Hispano-Suiza facilities in Spain, with licensed or knock-down manufacture performed by Mauser-affiliated workshops and subcontracting to Bofors for some maritime variants. Wartime disruptions led to clandestine assembly in regions controlled by different factions, while postwar production lines at plants tied to SEAT-era industrial conglomerates continued limited refurbishment and parts manufacture. International licensed production and overhaul were handled by firms in France, United Kingdom, and neutral states where inventories of 20 mm ammunition and components were compatible.

Surviving Examples and Preservation

Surviving Hispano Mk II guns are preserved in aviation and military museums associated with collections featuring aircraft from the Spanish Civil War and World War II, including display mounts alongside restored airframes from manufacturers like Supermarine, Hawker, Messerschmitt, and Heinkel. Static displays and conserved naval mounts appear in museums curated by institutions in Madrid, Seville, Paris, London, and Berlin. Private collectors and restoration groups working with organizations such as historical flight foundations have repurposed Mk II components for demonstration aircraft and recovered examples are subjects of study in technical archives maintained by former firms like Hispano-Suiza and successor engineering schools.

Category:Autocannon Category:20 mm artillery