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Miloch
March 10th 19, 02:12 PM
https://en.wikipedia.org/wiki/Martin_Maryland

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
they later named it the Maryland.

In response to a United States Army Air Corps light bomber requirement issued in
1938, the Glenn L. Martin Company produced its 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
nine-cylinder Wright R-1820 Cyclone engines, although 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 (463 km/h).

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 prewar contemporaries. The crew of three was
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 22 June 1940.


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

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 entered service only 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. 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.
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. 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

Just before the Franco-German Armistice, the remaining 75 planes on the French
order were signed over to the United Kingdom. 32 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.

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 East 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. 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 and
were mainly used for target towing duties. 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.

Specifications (Maryland Mk I)

General characteristics
Crew: three (pilot, navigator/bomb aimer/gunner and 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
Maximum speed: 304 mph (489 km/h) at 13,000 ft (3,962 m)
Cruise speed: 248 mph (399 km/h)
Range: 1,300 miles (2,100 km)
Service ceiling: 29,500 ft (8,991 m)
Rate of climb: 2,400 ft/min (12 m/s)
Wing loading: 28.5 lb/ft² (139.1 kg/m²)
Power/mass: 0.157 hp/lb (259 W/kg)

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)




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