Those two squadrons later moved to the South Pacific, and then began combat sorties on November 15, 1942, while other B-26Bs replenished some 22nd and 38th Group losses. In 1943, however, the B-26s in the Pacific were replaced by B-25s, whose longer range and shorter takeoffs were more suitable for island-hopping than the fast, “hot” Martins. One 22nd Group squadron, the 19th, used the B-26 until January 6, 1944, bringing the group’s total to 1,376 Marauder sorties and a loss of 77 aircraft, 38 to enemy action.
The first 307 B-26Bs had the R-2800-5, but the 2,000-hp R-2800-41 was introduced on June 17, 1942, on the first of 96 B-26B-2 aircraft. One .50-caliber flexible gun and one fixed gun were provided in the nose cone. Armor weighed 1,094 pounds. The similar R-2800-43, license-built by Ford, was used on the remaining Marauder models, along with the enlarged air intakes for desert conditions introduced on 28 B-26B-3s.
The B-26B-4 appeared in September 1942 with a lengthened nose wheel strut, equipment changes and 1,041 pounds of armor. Of 211 built, the last 141 added a pair of .50-caliber waist guns firing through side hatches at the fuselage bottom; an arrangement previously seen on some aircraft modified by combat units. Four .50-caliber fixed guns could be arranged in outside packages below the pilots’ cabin. Most of the early B-26B models were reworked at Omaha to incorporate the armament changes of the B-4 version and became known as B-26B-1s.
The first AAF Marauder group to cross the Atlantic was the 319th, which trained at Barksdale Field on B-26A-1s, and began to fly 57 B-26Bs to England in September 1942, but accidents and bad weather left the group with only 34 B-26Bs. In November, 25 reached Algeria to begin combat on November 28. Withdrawn in February after 17 losses on 165 sorties, it was rebuilt to full 64-plane strength and returned to combat in June 1943.
While the 17th and 320th groups had also been assigned to support North African operations, their route was changed to the South Atlantic. The 17th Group, the pioneer B-25 Mitchell outfit that had converted to B-26B and B-26B-2s at Barksdale Field in summer 1942, flew 57 over the South Atlantic to North Africa (losing three), and made its first combat mission over Tunis on December 30, 1942. The third B-26 group in the Mediterranean area with the 12th Air Force was the 320th, which trained at MacDill Field and entered combat on April 22, 1943, with B-26B-4s.
Nine new AAF medium bomber groups had been activated in 1942 as Marauder units, but it was in this period that criticism of the type reached its heights. A series of bad accidents in training the new pilots had brought upon the B-26 such names as “Widow Maker” and “Flying Prostitute”. In the United States, the B-26 accident rate was much higher than that of the B-25, and despite improved training methods after 1942, accident rate was 55 per 100,00 flying hours from 1942 to 1945, compared to 33 for the B-25.
The Marauder’s bad reputation at home contrasted sharply with its success in combat, and is to be explained primarily by the pilots involved. Increases in weight were steadily making the B-26’s wing loading, and therefore its stalling and landing speeds, higher and higher. The veteran pilots of the overseas units had the experience to deal with such an aircraft, the new pilots at home did not. Many of the new pilots had not flown any twin-engine aircraft at all, and when inexperienced ground crews and overloading of the type was added, the accident rate was understandable.
Air Force inspection boards, therefore, decided to solve the problems by a new training program and accepting Martin’s offer to enlarge the aircraft’s wing. The new wing increased span from 65 to 71 feet and area from 602 to 658 square feet and was introduced on the 642nd B-26B and the new B-26C models. In the meantime, in July and again in October 1942, the AAF considered canceling the B-26, but commendations from the 5th Air Force, kept it in production.
To increase forward firepower, several B-26s were fitted with two 20-mm and two .50-caliber guns in the nose, and tried by the 28th Group in the Aleutians. The system adopted for production was four .50-caliber fixed guns in outside packages. In September 1942, the 28th B-26B had been tested with the fixed package guns and a new Bell tail turret, and these features were to be included on the wide-winged production aircraft as soon as possible.
The first Marauder with the new wing and larger tail was the B-26C-5-MO ordered on June 28, 1941, from a new Martin factory in Omaha. The first three were accepted in August 1942, and 86 were accepted by the year’s end. The wide wing was also introduced on Baltimore’s production line after 641 short-winged B-26Bs had been built by the end of 1942. The first was the B-26B-10-MA in January 1943, with 150 built on the original B-26B contract.
Except for place of manufacture, the B-26B-10 and the 175 B-26C-5s were alike. Twelve .50-caliber guns with 4,250 rounds were carried: one flexible and one fixed gun in the nose, four fixed package guns on the sides, two in the top turret, two in the lower waist, and two in the tail.
A power-operated Bell M-6 tail turret with a 90-degree cone of fire was introduced in March 1943 on the B-26B-20-MA and B-26C-10-MO. The double bomb bay could accommodate two 2,000, four 1,000, eight 500, or thirty 100-pound bombs, or 1,000 gallons of extra fuel. However, on the B-26B-25 and B-26C-30 and later models, the external torpedo rack and the rear bays were deleted. While four 1,000-pound bombs could still be carried, there was room now for just six 500 or twenty 100-pound bombs, or 500 gallons of added fuel. The nose fixed gun was also deleted from the B-26B-45 and later models.
Production of 1,883 B-26Bs ended at Baltimore in February 1944, with the last B-26B-55-MA. In addition, Martin built 208 AT-23As for the Air Force. First appearing in August 1943, the AT-23A had no armor, guns, or turret, but had a tow target windlass installed for its gunnery training mission.
Marauder production ended at Omaha on April 4, 1944, after 1,210 B-25C-5 to B-25C-45-MO and 375 AT-23B tow target trainers. Of the tow target ships, the U.S. Navy got 200 in September-October 1943 and the last 25 in 1944. Known as the JM-l, their bright orange yellow finish was familiar at Navy stations around the country. Air Force AT-23Bs, however, retained a natural metal finish and were redesignated TB-26 in 1944.