Martin B-26 Marauder

The Martin B-26 Marauder is a twin-engined medium bomber designed and produced by the American aircraft manufacturer Glenn L. Martin Company.

Development of the B-26 started in 1939 in response to a United States Army Air Corps (USAAC) requirement for a new twin-engined bomber. Martin's proposal, internally designated as the Model 179, featured numerous firsts for the service, including powered turrets, self-sealing fuel tanks, and an all-plastic nose. Martin's submission was selected as the winner; by September 1940, almost 1,000 aircraft had been ordered. On 25 November 1940, the first B-26, effectively the prototype, performed its maiden flight; three months later, deliveries of production aircraft commenced to the United States Army Air Force (USAAF). The B-26 was built at two locations: Baltimore, Maryland, and Omaha, Nebraska, by Glenn L. Martin. In total, 5,288 aircraft were produced between February 1941 and March 1945; while the majority of B-26s were delivered to the USAAF, 522 aircraft were flown by the Royal Air Force and the South African Air Force. It saw extensive service during World War II, being first used in the Pacific Theater in early 1942. The majority of B-26s were deployed in the European and Mediterranean theatres, largely from bases in England and, following D-Day, on the European continent, providing tactical support to advancing Allied troops.

Early on in the B-26's service, it acquired the reputation of a "widowmaker" due to the early models' high accident rate during takeoffs and landings. This was because the Marauder had to be flown at precise airspeeds, particularly on final runway approach or when one engine was out. The unusually high speed on short final runway approach was intimidating to many pilots who were used to much slower approach speeds, and when they slowed to speeds below those stipulated in the manual, the aircraft would often stall and crash.Ethell 1995, p. 242. The B-26 became a safer aircraft once crews were retrained, and after aerodynamic modifications (an increase of wingspan and wing angle-of-incidence to give better take-off performance, along with the adoption of a larger vertical stabilizer and rudder).Ethell 1995, pp. 242–243. By the end of World War II, the B-26 had achieved the lowest loss rate of any bomber operated by the USAAF.Ethell 1995, p. 243. By the time the United States Air Force was created as an independent military service separate from the USAAF in 1947, all B-26s had been retired from US service. After the Marauder was retired, the unrelated ground attack aircraft Douglas A-26 Invader assumed the "B-26" designation, which led to confusion between the two aircraft.

Design and development

On 11 March 1939, the United States Army Air Corps (USAAC) issued Proposal No. 39-640 specifying a twin-engined medium bomber capable of carrying a bombload over a range of at a maximum speed in excess of .Merriam July 2000, p. 7. It was also stipulated that the envisioned aircraft ought to be powered by one of several specific engines, these being the Wright R-2600-92 Twin Cyclone, the Wright R-2800, and the Wright R-3350. Furthermore, a relatively short development schedule was specified; in addition to the selection being made within 6 months of issuing, the winner would be expected to commence delivery of production aircraft within 24 months of the production contract's issuing.Johnson 2008, pp. 74-76.

The Glenn L. Martin Company ordered its design team, headed by Peyton M. Magruder, to design a suitable aircraft to fulfil the requirement.Johnson 2008, p. 79. To minimise drag, it was decided to adopt a completely circular cigar-shaped fuselage along with tricycle landing gear. While a twin-fin tail unit had been favoured early on, the design team instead opted for a single-fin arrangement as this provided better visibility for a tail gunner. Noting that no minimum landing speed had been stipulated, the design team opted for a high (for the era) wing loading that required a touch-down speed in excess of . It was decided to power the type using a pair of then-experimental Pratt & Whitney R-2800 Double Wasp radial engines, installed within nacelles slung under the wing, each driving a four-bladed propeller. These engines were normally manufactured at the Ford Dearborn Engine plant in Dearborn, Michigan.

On 5 July 1939, the company submitted its response, which was internally designated Model 179. Following a competitive evaluation of the submissions, it was determined that the Model 179 was superior to all other proposals and thus Martin was awarded an initial production contract for 201 aircraft, which had been assigned the service designation B-26.Air International January 1988, p. 23. Due to the urgency of the requirement and Martin having declaring that they were unlikely to be capable of providing all 385 aircraft sought by the requirement within the allocated timeframe, the second-place submission was also selected for production and ultimately entered service as the North American B-25 Mitchell.Johnson 2008, pp. 76, 79. The B-26 went from the drawing board to an operational bomber in roughly two years.Trent 2008, p. 647. Additional orders for a further 930 B-26s followed in September 1940, even though to the type was yet to fly.Air International January 1988, p. 25.

The B-26 was a shoulder-winged monoplane of all-metal construction, fitted with a tricycle landing gear. It had a streamlined circular-section fuselage housing the crew, consisting of a bombardier in the nose, armed with a machine gun, a pilot and co-pilot sitting side by side, with positions for the radio operator and navigator behind the pilots. The bombardier's position was within an all-plastic nose, which was a first for the USAAF. Furthermore, the B-26 was the first USAAF aircraft to be fitted with powered turrets, and one of the first to be fitted with a tail turret. The defensive armaments consisted of a dorsal turret armed with two machine guns and an additional machine gun that was fitted in the tail.Johnson 2008, pp. 79, 82.

Two bomb bays were located within the middle of the fuselage, capable of carrying of bombs, although in practice such a bomb load significantly reduced the aircraft's range, thus the aft bomb bay was usually fitted with additional fuel tanks instead of bombs. The B-26 was the first USAAF aircraft to be equipped with self-sealing fuel tanks. The wings were of low aspect ratio and relatively small in area for an aircraft of its weight, giving the required high performance, but also resulting in a wing loading of for the initial versions, which was the highest of any aircraft accepted for service by the USAAF prior to the introduction of the Boeing B-29 Superfortress, which possessed the then-astonishing wing loading of (although both would be considered lightly loaded by the standard of combat aircraft of the next decade).Air International January 1988, pp. 23–25. The aircraft's handling qualities, while not docile, were determined to be acceptable.

The first B-26, with Martin test pilot William K. "Ken" Ebel at the controls, flew on 25 November 1940 and was effectively the prototype.Grant May 1944, p. 160. Following 133 hours of testing, the first four B-26s were deliveries to the USAAF in February 1941.Johnson 2008, pp. 79, 83. One month later, the service started accelerated service testing of the type at Patterson Field, near Dayton, Ohio.

Operational history

The B-26 Marauder was used mostly in Europe and the Mediterranean, but also saw action in the Pacific theatre as well. In early combat, the aircraft took heavy losses, but was still regarded as being one of the most successful medium-range bombers flown by the USAAF.

By the end of World War II, it had flown more than 110,000 sorties, dropped 150,000 tons of bombs, and had been used in combat by British, Free French, and South African forces in addition to US units. In 1945, when production of the B-26 was terminated, 5,266 aircraft had been built.

Pacific Theater The B-26 began to equip the 22nd Bombardment Group at Langley Field, Virginia, in February 1941, replacing the Douglas B-18 Bolo, with a further two groups, the 38th and 28th, beginning to equip with the B-26 by December 1941.Air International February 1988, p. 75. Immediately following the Japanese Attack on Pearl Harbor, the 22nd BG was deployed to the South West Pacific,Donald 1995, p. 76.Swanborough and Bowers 1963, p. 335. first by ship to Hawaii, then its air echelon flew the planes to Australia. The 22nd BG flew its first combat mission, an attack on Rabaul, which required an intermediate stop at Port Moresby, New Guinea, on 5 April 1942.Johnson 2008, p. 83.

A second group, the 38th, began receiving B-26s in November 1941 and began transitioning into them at Patterson Field, Ohio. There, the 38th continued the testing of the B-26, including its range and fuel efficiency. Immediately after the entry of the United States into World War II, plans were tentatively developed to send the 38th BG to the South West Pacific and to equip it with B-26Bs fitted with more auxiliary fuel tanks and provisions for carrying aerial torpedoes. Three 38th BG B-26BsLetters from Maj. James F. Collins 1984–86. were detached to Midway Island in the buildup to the Battle of Midway, and two of them, along with two B-26s detached from the 22nd BG, carried out torpedo attacks against the Japanese Fleet on 4 June 1942. Two were shot down and the other two were so badly damaged that they were written off after the mission. Their torpedoes failed to hit any Japanese ships, although they did shoot down one Mitsubishi A6M Zero fighter and killed two seamen aboard the aircraft carrier Akagi with machine-gun fire.Parshall and Tulley 2005, pp. 151–153. The crew of one B-26, Susie Q, after dropping their torpedo, were pursued by fighters; seeking an escape route, they flew directly along the length of the Akagi, braving antiaircraft fire – to the point the pursuing Japanese fighters had to hold fire temporarily, to avoid hitting the flagship. Another B-26, seriously damaged by antiaircraft fire, did not pull out of its run, and instead flew directly at Akagis bridge. Either attempting a suicide ramming, or out of control, the plane narrowly missed striking the carrier's bridge, and crashed into the ocean.Parshall and Tully 2005, pp. 151–152.Lundstrom 2005, p. 337.

From around June 1942, B-26 squadrons of the 38th BG were based in New Caledonia and Fiji. From New Caledonia, missions were flown against Japanese bases in the Solomon Islands. On one occasion, a B-26 was credited with shooting down a Kawanishi H6K flying boat. In 1943, the B-26 was decided to be phased out of operations in the South West Pacific Theater in favor of the North American B-25 Mitchell. Nevertheless, the 19th Bombardment Squadron of the 22nd BG continued to fly missions in the B-26. The B-26 flew its last combat mission in the theater on 9 January 1944.

Two more squadrons of torpedo-armed B-26s equipped the 28th Composite Group and were used for anti-shipping operations in the Aleutian Islands Campaign, but no records of any successful torpedo attack by a USAAF B-26 have been found.

Comedian George Gobel famously joked about being an instructor for this aircraft at Frederick Army Airfield (now Frederick Regional Airport) during the Pacific battles, boasting, "not one Japanese aircraft got past Tulsa".

Mediterranean Theater