The B-26C was the designation given to a version of the B-26B manufactured at a new factory built by the government for Martin at Omaha, Nebraska. Even before Pearl Harbor, the US government had already sensed the coming of war, and began a massive expansion of the American aircraft industry. As part of this program, the government built a whole series of new aircraft plants which were to be leased to aircraft manufacturers for the purpose of fulfilling military contracts. Most of these plants were in the Midwest or Western states, well out of range, it was hoped, from German raiders. The plant in Omaha was built at Fort Crook (now Offut AFB) and was leased to Martin for the manufacture of the B-26 Marauder. The plant was formally turned over to Martin on January 1, 1942.
At the same time, the Martin-Omaha Modification Center was built adjacent to Fort Crook, and began operating in March of 1942. The Center was given the task of modifying Marauders fresh off the Baltimore production line to incorporate the latest government change orders to make them more combat-capable.
In parallel, the Ford Motor Company was provided with a license to build Pratt & Whitney Double Wasp engines at a new River Rouge engine plant at Dearborn, Michigan.
The B-26C had been initially ordered on June 28, 1941. However, there were inevitable delays in bringing such a massive production effort to full fruition, and it was not until August of 1942 that the first Omaha-built B-26C was ready for flight.
The B-26C was essentially identical to the Baltimore-built B-26B, and followed more or less the same evolution during its production lifetime. However, all B-26Cs were built with the new larger wing--the B-26C was in fact the first Marauder to appear with the new larger wing, the larger wing having been introduced on the Omaha line before it appeared on the Baltimore line. The wingspan was increased to 712 feet and the wing area rose to 713 square feet. This lowered the wing loading to 51.5. A larger vertical tail was also fitted. The larger wing and tail assembly, plus the additional armament and armor, increased the weight by 1500 pounds. The top speed at 15,000 feet dropped to 282 mph and cruising speed declined to 214 mph.
The armament changes intitially done on Martin-Omaha modified B-26Bs plus the package guns introduced on the B-26B-4 were made standard. The waist gun doors were enlarged and moved aft to improve the field of fire.
The first three B-26Cs were accepted in August of 1942, and 86 B-26C-5-MO aircraft were accepted by the end of 1942.
In early 1943, 60 B-26C-5-MO aircraft were subjected to a substantial weight-reduction program, in which the co-pilot position was deleted and some extra equipment was removed. These planes were redesignated B-26C-6-MO. However, commanders in the field objected strenuously to the absence of the co-pilot, and all of these planes were eventually converted back to a two-pilot configuration.
The B-26C-10-MO was identical to the B-26C-5-MO. It was fundamentally identical to the Baltimore-built B-26B-10-MA, which marked the first introduction of the "long-wing" on the Middle River production line.
The B-26C-15-MO differed only in having the fixed oxygen system Type A-9 regulator deleted and improved SCR-595A IFF equipment fitted. Except for the place of manufacture, the B-26C-15-MO and B-26B-15-MA were identical.
The B-26C-20-MO introduced the Bell-designed power turret in the tail which replaced the hand-held setup previously used. Its guns were positioned below the gunner and afforded a wider field of fire. The guns were operated by a remotely-controlled linkage, but gunners usually preferred swinging the guns manually.
The B-26C-25-MO featured more armor plate for the Martin 250CE turret. Some examples not intended for overseas combat roles had the tail turret deleted.
Provisions for the external torpedo rack and the rear bomb bay were deleted from the B-26C-30-MO and later production blocks. A curved piece of armor plate was mounted externally to the left side of the fuselage to add extra protection for the pilot, and some extra armor was added behind the bombardier and around certain vital systems.
The B-26C-35-MO eliminated the carburetor de-icing system.
The C-40 model introduced "shark-nose" ailerons, which appeared from 42-43320 onward. All of these planes were subsequently converted to AT-23Bs.
The C-45 model incorporated a thicker grip on the control wheels, improvements in the hydraulic and electrical systems, and additional emergency systems. A ring and bead sight for the package guns was provided. The engine fire-extinguisher was reinstated as standard equipment. The aft bomb-bay was finally sealed up from this variant onward. In the middle of the production run, the forward-firing 0.50-inch machine gun in the nose was deleted. 26 examples were converted to AT-23Bs.
350 B-26C were manufactured as target tugs and were redesignated AT-23B. These AT-23Bs were later redesignated TB-26C. 225 AT-23Bs were transferred to the US Navy as JM-1s. The JM-1 was used by the Navy for target towing and other general utility duties. It was never used in combat. Many JM-1s were painted with a bright orange-yellow finish, but the USAAF AT-23Bs retained their natural metal finish.
A total of 1210 B-26Cs and 275 AT-23B target tugs were built at Omaha. The last B-26C (a B-26C-45-M0) was delivered in April of 1944. After that, Martin-Omaha switched over to the manufacture of the B-29 Superfortress.
41-34673/34847 Martin B-26C-5-MO Marauder 34681,34869/34693,34695,34702/34742, 34777/34787 converted to B-26C-6-MO 34680 modified as "XB-26E" 41-34848/34907 Martin B-26C-10-MO Marauder 41-34908/34997 Martin B-26C-15-MO Marauder 41-34998/35172 Martin B-26C-20-MO Marauder 41-35173/35372 Martin B-26C-25-MO Marauder 35370/35372 converted to AT-23B 41-35373/35572 Martin B-26C-30-MO Marauder 100 delivered to RAF as Marauder II FB415/FB517 35525/35572 converted to AT-23B 41-35573/35772 Martin B-26C-35-MO Marauder 35598/35620 converted to AT-23B 41/35773/35872 Martin B-26C-40-MO Marauder All converted to AT-23B 42-107471/107496 Martin AT-23B 42-107497/107830 Martin B-26C-45-MO Marauder 42-107831/107855 Martin AT-23B