Martin Maryland

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Model 167 Maryland
Martin Maryland RAF North Africa.jpg
RAF Marylands c. 1941
Role medium bomber
Manufacturer Martin
First flight 14 March 1939
Introduction 1940
Retired 1945
Status Out of service
Primary users Royal Air Force
South African Air Force
French Air Force
French Navy
Number built 450
Variants Martin Baltimore

The Martin Model 167 was an American-designed medium bomber that first flew in 1939. It saw action in World War II with France and the United Kingdom, where it was named the Maryland.

Design and development[edit]

Martin XA-22, 13 April 1939.

In response to a United States Army Air Corps light bomber requirement issued in 1938, the Glenn L. Martin Company produced their Model 167, which was given the official designation XA-22. Martin's design was a twin-engine all-metal monoplane, capable of around 310 mph (500 km/h) with a crew of three.

The XA-22 was not adopted for operational service in the U.S., as the contract was won by the Douglas DB-7, which became the A-20 Havoc, but Martin received foreign orders, and about 450 of these fast, twin-engined bombers were built.

The prototype Model 167W was powered by twin-row Pratt & Whitney R-1830-37 “Twin Wasp” engines, which were replaced in French production aircraft by single-row Wright “Cyclone 9” engines (the Twin Wasps were then restored for the British Maryland). All versions of the Model 167 were armed with six machine guns, four fixed guns in the wings (mainly for ground attack), one dorsal gun and one ventral gun. In the prototype these guns were all 0.30 in Browning machine guns. The dorsal gun was mounted in a fully retractable turret. The French aircraft used license built Belgian Fabrique Nationale FN-Brownings, and used a lighter semi-retractable dorsal turret. The weight saved helped to increase the top speed to 288 mph.

The Model 167 was a fairly typical twin engined bomber of the period. The most unusual feature of the Model 167 was the very narrow fuselage although it was shared with a number of late pre-war contemporaries. The crew of three were carried in two isolated compartments – the bombardier sat in the nose below the pilot and the gunner was in the mid-upper twin-machine gun turret in a separate rear compartment, isolated by a bulkhead.

Glenn L. Martin doubled the size of the Baltimore factory, and built all 115 aircraft in six months, but they were then prevented from delivering them by a US government arms embargo. Despite this the French placed an order for an additional 100 aircraft. The embargo was lifted in October 1939, and the 115 aircraft from the first order were delivered by late November 1939. Deliveries then slowed down, and only 25 of the second batch reached France before the Armistice of June 1940.

Operational history[edit]

French service[edit]

A captured French Martin 167F at Aleppo, Syria, in 1941.

Facing a massive German arms buildup and desperate for modern aircraft, the French Air Force purchased U.S. aircraft of numerous types in the late 1930s. Martin received an order for more than 200 167 Fs which incorporated French-specific equipment such as metric instruments. French officials expected deliveries to begin in January 1939 but the type, locally designated Glenn Martin 167 A-3 only entered service in early 1940.

Notably, because of the U.S. embargo on arms exports after the beginning of World War II, many aircraft were impounded for two months before being shipped to Europe. When the Germans invaded France there were only four Groupes de bombardement (bomber squadrons) equipped. The Glenns were quickly sent to the front lines where they performed well with their adequate speed and excellent maneuverability for an aircraft in this class.[1] In about 400 sorties, they suffered a 4% loss rate, much better than the 16% endured by LeO 451 crews against similar targets.

Immediately before the June 1940 Armistice, units flying the Glenn Martin 167 were evacuated to French North Africa to avoid capture by the Germans. One of them landed in Spain and was interned, being tested by the Spanish Air Force.[citation needed] Some examples were transferred to the Aéronautique Navale. During Vichy rule of the French empire, French Martins bombed British Commonwealth forces, most notably during the Syria-Lebanon campaign of 1941.[2] As French North Africa got back in the Allied camp in 1943, M.167s were replaced with more modern Allied types, including the Martin B-26 Marauder.

Approximately 215 Martin 167s were delivered to France.

British service[edit]

Martin Maryland bombers fly past in formation, North Africa 1941

Just before the Franco-German Armistice, the remaining 75 planes on the French order were signed over to the United Kingdom. Thirty-two aircraft had been completed to French specifications and were converted to British requirements in the UK. Engines were changed from the Cyclone 9 to the Pratt and Whitney Twin Wasp and various weapons and instruments were replaced. The last 43 of the order were completed as required by Glenn Martin. All these aircraft received the designation Maryland Mk.I. A further 150 aircraft had been ordered directly by Britain with two-speed superchargers on their Twin Wasps and were designated Maryland Mk.II.[3]

Many of the aircraft were shipped to Egypt and Malta in time for the 1941 fighting there. The RAF used the aircraft mainly for photo-reconnaissance operations in North and Eastern Africa, being faster than the Bristol Blenheim. A Maryland bomber was the aircraft that photographed the Italian fleet before and after the Battle of Taranto on 11 November 1940.[4] The pilot of that Maryland was Adrian Warburton, who scored his five confirmed kills with the Maryland's forward-firing guns.

Three Maryland Mk.I aircraft were transferred to the British Fleet Air Arm[5] and were mainly used for target towing duties.[6] On 22 May 1941, a Maryland of 771 Naval Air Squadron based at Hatston in the Orkney Islands, reported that the German battleship Bismarck had left Bergen, confirming that she was breaking-out into the Atlantic.[7]

Operators[edit]

 France
 South Africa
 United Kingdom

Specifications (Maryland Mk I)[edit]

General characteristics

  • Crew: 3 (Pilot, Navigator/Bomb Aimer/Gunner & Radio Operator/Gunner)
  • Length: 46 ft 8 in (14.2 m)
  • Wingspan: 61 ft 4 in (18.7 m)
  • Height: 16 ft 3 in (5.0 m)
  • Wing area: 537 ft² (49.9 m²)
  • Empty weight: 10,586 lb (4,802 kg)
  • Loaded weight: 15,297 lb (6,939 kg)
  • Max. takeoff weight: 16,809 lb (7,624 kg)
  • Powerplant: 2 × Pratt & Whitney R-1830-S1C3-G "Twin Wasp" radial engine, 1,050 hp (783 kW) each
  • Propellers: 10 ft 11 in (3.3 m) Hamilton Standard 3T50 three-bladed constant-speed metal propellers
  • Fuel capacity: 514 imperial gallons (2,336 litres)

Performance

Armament

  • Guns: 4 x .303 (7.7 mm) Browning Mk II machine guns in outer wings with 750 rpg, 1 × .303 in (7.7 mm) Vickers K machine gun in dorsal and ventral step positions each with 5 x 97-round magazines
  • Bombs: 2,000 lb (907 kg) internally; (Usually 4 x 500 lb (227 kg) bombs)

See also[edit]

Related development
Aircraft of comparable role, configuration and era
Related lists

References[edit]

Notes
Bibliography
  • Bishop, Chris. The Encyclopedia of 20th Century Air Warfare. London: Amber Books Ltd, 2004. ISBN 1-904687-26-1.
  • Cuny, Jean. "Glenn Martin 167 in French service". Journal of American Aviation Historical Society. Volume 10, No. 1, Spring 1965.
  • Mondey, David. American Aircraft of World War II (Hamlyn Concise Guide). London: Bounty Books, 2006. ISBN 978-0-7537-1461-4.
  • Munson, Kenneth. Fighters and Bombers of World War II: 1939-45. London: Blandford Press Ltd, 1969. ISBN 0-9637110-4-0.
  • Shores, Christopher F. "Martin Maryland and Baltimore variants". Aircraft in Profile, Volume 11. Windsor, Berkshire, UK: Profile Publications Ltd., 1972, pp. 217–241.
  • Wagner, Ray. "American Combat Planes, Third Enlarged Edition". New York: Doubleday & Company, 1982, pp. 178–179. ISBN 978-0-3851-3120-9.

External links[edit]