Military Factory logo

Martin MB-1 / Glenn Martin Bomber

United States (1918)

Detailing the development and operational history of the Martin MB-1 / Glenn Martin Bomber Reconnaissance / Bomber Biplane Aircraft.

 Entry last updated on 4/3/2017; Authored by Staff Writer; Content ©

  Martin MB-1 / Glenn Martin Bomber  
Picture of Martin MB-1 / Glenn Martin Bomber Reconnaissance / Bomber Biplane Aircraft

Only nine Martin MB-1 series bombers were completed before the end of hostilities in World War 1.

The Martin MB-1 (also known as the "Glenn Martin Bomber") became the first American-designed heavy bomber type to be purchased in quantity in the First World War, becoming the mainstay of the United States Army Air Service (USAAS) for a time. The system was a two-engine bomber of indigenous creation (previous US bombers were simply license production derivatives of European origin) and was designed by the Glenn Martin Company. In the end, only nine full-operational systems would become available by war's end but the type would soldier on until being replaced in 1920 by the more capable Martin MB-2 series.

Power was derived from two Liberty 12-A engines mounted between the upper and lower wing assemblies. Each engine developed a reported 400 horsepower and straddled the fuselage where three to four crewmembers were called upon to man the various open-cockpit stations. Armament was defensive and was made up of no fewer than 5 x 7.62mm machine guns in various positions about the fuselage including the bow nose mount. Offensive firepower consisted of up to 2,000lbs of ordnance. The undercarriage was of a fixed type and consisted of four wheels. First production examples were received in October of 1918.
Picture of the Martin MB-1 / Glenn Martin Bomber Reconnaissance / Bomber Biplane Aircraft
Picture of the Martin MB-1 / Glenn Martin Bomber Reconnaissance / Bomber Biplane Aircraft

The MB-1 was designed to replace the Handley-Page O/400 bomber series of British design and the Caproni bomber series of Italian design. The MB-1 came about at a time when the United States depended heavily on the purchase of foreign designs or all-out completed production models to maintain a workable military presence so the arrival of the MB-1 was quite a historic footnote for the nation. The system was called upon to fulfill the primary role of reconnaissance platform with a secondary role as a dedicated bomber. It would serve only a few short years in a military capacity before being replaced in frontline service by the aforementioned MB-2 series, which was in essence a further developed version of the MB-1 series.

A few modified MB-1 models existed and are worthy of note. These include an MB-1 with a 37mm cannon mounted in the 7.62mm bow-mount machine gun position. This particular MB-1 is designated as the GMC for "Glenn Martin Canon" and known by the serial AS62951. Additionally, the MB-1 with serial AS39059 sported a third Hispano-Suiza engine in the nose. A ten-passenger model existed as the GMP ("Glen Martin Passenger"). The MB-1 also served for a time as a mail carrier plane in the form of the T-1 in the post-war years.
Martin MB-1 / Glenn Martin Bomber Specifications
National Flag Graphic
United States
Year: 1918
Type: Reconnaissance / Bomber Biplane Aircraft
Manufacturer(s): Glenn Martin Company (Martin) - USA
Production: 22
Supported Mission Types
Ground Attack
Close-Air Support
Airborne Early Warning
Electronic Warfare
Aerial Tanker
Passenger Industry
VIP Travel
Business Travel
Special Forces
Crew: 3 or 4
Length: 44.09 ft (13.44 m)
Width: 71.49 ft (21.79 m)
Height: 14.70 ft (4.48 m)
MTOW: 10,223 lb (4,637 kg)

Installed Power
2 x Liberty 12-A engines developing 400 horsepower each.

Standard Day Performance
Maximum Speed: 104 mph (168 kph; 91 kts)
Maximum Range: 390 mi (627 km; 339 nm)
Service Ceiling: 12,247 ft (3,733 m; 2.32 mi)

2 x 7.62mm Lewis machien guns in bow position
2 x 7.62mm Lewis machine guns in upper rear fuselage.
1 x 7.62mm Lewis machine gun in lower rear fuselage.

Up to 2,000lb of ordnance

Operators List
United States

Series Model Variants
• MB-1 - Martin Company Designation / Military Designation.
• GMB "Glen Martin Bomber" - United States Army Air Service designation for MB-1 series.
• GMT "Glenn Martin Transcontinental" - Fitted with fuel tanks for increased range.
• GMC "Glen Martin Canon" - Fitted with 1 x 37mm cannon replacing bow-mounted 7.62mm machine gun.
• GMP "Glenn Martin Passenger" - Accommodations for up to 10 passengers; redesignated to T-1.
• MBT "Martin Bombers - Torpedo" - Torpedo Bomber Variant; used by the United States Navy.
• MT "Martin Torpedo" - Used by the United States Navy; based on MB-1 system with wing assembly of MB-2 bombers; redesignated to TM-1.
• T-1 - GMP Redesignation
• TM-1 - MT Redesignation
• MB-1 / NBS-1 - "Improved" MB-1 Model Series

Images Gallery