The Martin BM was a 1930s American

torpedo bomber A torpedo bomber is a military aircraft designed primarily to attack ships with aerial torpedoes. Torpedo bombers came into existence just before the World War I, First World War almost as soon as aircraft were built that were capable of carryin ...

built by the

Glenn L. Martin Company The Glenn L. Martin Company, also known as The Martin Company from 1917 to 1961, was an American aircraft and aerospace industry, aerospace manufacturing company founded by aviation pioneer Glenn L. Martin. The Martin Company produced many impo ...

for the United States Navy.

Design and development

To meet the requirement for a special-purpose

dive bomber A dive bomber is a bomber aircraft that dives directly at its targets in order to provide greater accuracy for the bomb it drops. Diving towards the target simplifies the bomb's trajectory and allows the pilot to keep visual contact througho ...

for the

United States Navy The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 millio ...

and

United States Marine Corps The United States Marine Corps (USMC), also referred to as the United States Marines or simply the Marines, is the maritime land force service branch of the United States Department of Defense. It is responsible for conducting expeditionar ...

, the U.S. Navy's

Bureau of Aeronautics The Bureau of Aeronautics (BuAer) was the U.S. Navy's material-support organization for naval aviation from 1921 to 1959. The bureau had "cognizance" (''i.e.'', responsibility) for the design, procurement, and support of naval aircraft and rela ...

designed a

biplane A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While ...

with fixed-tailwheel

landing gear Landing gear is the undercarriage of an aircraft or spacecraft that is used for taxiing, takeoff or landing. For aircraft, it is generally needed for all three of these. It was also formerly called ''alighting gear'' by some manufacturers, s ...

designated Bureau Design 77. It had room for two crew in tandem. Two prototypes were ordered in June 1928, one from Martin (designated the XT5M-1) and one from the

Naval Aircraft Factory The Naval Aircraft Factory (NAF) was established by the United States Navy in 1918 in Philadelphia, Pennsylvania. It was created to help solve aircraft supply issues which the United States Department of the Navy, Navy Department faced upon the ...

(designated the XT2N-1). Martin moved to a new factory in

Baltimore Baltimore is the most populous city in the U.S. state of Maryland. With a population of 585,708 at the 2020 census and estimated at 568,271 in 2024, it is the 30th-most populous U.S. city. The Baltimore metropolitan area is the 20th-large ...

Maryland Maryland ( ) is a U.S. state, state in the Mid-Atlantic (United States), Mid-Atlantic region of the United States. It borders the states of Virginia to its south, West Virginia to its west, Pennsylvania to its north, and Delaware to its east ...

, where the XT5M-1 was built, and it was first flown on 17 May 1929. It was powered by a Pratt & Whitney R-1690-22 Hornet radial engine. During testing, the aircraft suffered structural damage during a pullout from a dive and had to be returned to the factory. After a redesign and rebuilding of the wings, the XTM5-1 was handed over to the Navy in May 1930 for service trials. Following further tests during 1930, the Navy ordered 12 aircraft with a more powerful R-1690-44 engine in April 1931, designating them the BM-1. A further order for four BM-1 aircraft was followed by an order in October 1931 for 16 of the BM-2, a variant with minor improvements.

Operational history

The first production BM-1, ''A8879'', was delivered to the U.S. Navy at Naval Air Station Anacostia in

Washington, D.C. Washington, D.C., formally the District of Columbia and commonly known as Washington or D.C., is the capital city and federal district of the United States. The city is on the Potomac River, across from Virginia, and shares land borders with ...

, for acceptance testing in September 1931. The Navy refused to accept the type after ''A8879'' had a fatal crash during a test dive in September 1931. Meanwhile, the prototype was flown aboard the

aircraft carrier An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and hangar facilities for supporting, arming, deploying and recovering carrier-based aircraft, shipborne aircraft. Typically it is the ...

from November 1931 to prove its suitability as a carrier aircraft. Martin modified the second production aircraft, used the same serial as the crashed aircraft, and delivered it to the Navy in January 1932. The Navy accepted the second ''A8879'' on 27 February 1932 and the delivery of 15 more followed, with the last accepted in July 1931. In June 1932 the BM-1s were delivered to Torpedo Squadron 1 (VT-1S) aboard the aircraft carrier to replace the squadron's

Martin T4M The Martin T4M was an United States of America, American torpedo bomber of the 1920s. A development by the Glenn L. Martin Company of their earlier Martin T3M, and, like it a single-engined biplane, the T4M served as the standard torpedo bomber ...

s. In March 1933 the squadron was redesignated VT-1B when it became part of the Battle Force. By October 1932 it had ten BM-1s and ten BM-2s in service. In July 1934, the U.S. Navy formed Bombing Squadron 3 (VB-3B) for service aboard the aircraft carrier operating the BM-1 and BM-2, which the squadron flew until February 1935. Other carrier squadrons — including VB-5 and VT-5 aboard and VT-6 aboard — also operated Martin BMs for short periods before they moved on to other aircraft. By the middle of 1938 only a small number of Martin BMs remained in service, most with the test and evaluation squadrons VX-3D4 and VX-4D4 based at

Philadelphia Philadelphia ( ), colloquially referred to as Philly, is the List of municipalities in Pennsylvania, most populous city in the U.S. state of Pennsylvania and the List of United States cities by population, sixth-most populous city in the Unit ...

Pennsylvania Pennsylvania, officially the Commonwealth of Pennsylvania, is a U.S. state, state spanning the Mid-Atlantic (United States), Mid-Atlantic, Northeastern United States, Northeastern, Appalachian, and Great Lakes region, Great Lakes regions o ...

. By the end of 1939, all BM-1s and BM-2s were out of service. Martin built an additional aircraft designated the XBM-1 for trials and testing with the

National Advisory Committee for Aeronautics The National Advisory Committee for Aeronautics (NACA) was a United States federal agency that was founded on March 3, 1915, to undertake, promote, and institutionalize aeronautical research. On October 1, 1958, the agency was dissolved and its ...

Variants

;XT5M-1 :Prototype with R-1690-22 engine, one built. ;XT2N-1 :Prototype built by Naval Aircraft Factory ;BM-1 :Production aircraft, 17 built. ;BM-2 :Production aircraft with minor changes, 16 built. ;XBM-1 :Additional aircraft for trials and testing, transferred to NACA in 1940.

Operators

; *

**VT-1S/VT-1B/VB-1B/ BM Martin BM1 1920s United States bomber aircraft">Martin BM1 Single-engined tractor aircraft Carrier-based aircraft">Single-engined tractor aircraft">1920s United States bomber aircraft">Martin BM1 Single-engined tractor aircraft Carrier-based aircraft Biplanes Aircraft with fixed conventional landing gear Single-engined piston aircraft