Martin B-26B-MA (S/N 41-17545, the second B-26B built). This aircraft was used for testing and prototyping. Note the solid nose and the late-model air intakes; this is probably the CB-26B (cargo/transport) prototype. (U.S. Air Force photo)
The first 641 (of 1883) Martin B-26Bs built were basically improved versions of the A model. Changes included replacement of the single .50-cal. machine gun with twin guns in the tail and a tunnel gun mounted in the rear crew entry hatch for increased protection below and behind the aircraft. Block 3 and 4 aircraft had large carburetor intakes necessary for more robust sand filters. Block 4 aircraft had a longer nose wheel strut, which was designed to improve take-off performance by increasing the angle of attack. Late production block 4 aircraft deleted the tunnel gun and replaced it with waist gunner positions location near the tail below the aircraft centerline.
Great Britain received 19 B-26B-4s as Marauder Mk.1A.
Major changes were incorporated into the B-26B-10 and later including a wing span increase of six feet and a taller vertical stabilizer.
Twin .50-cal. tail turret and tunnel gun
B-26B-MA with R-2800-41 radials
Large carb. intakes; -43 radials
Improved B-26B-3-MA; to RAF as Mk.1A
TECHNICAL NOTES (B-26B-2-MA): Armament: Four .50-cal. and two .30-cal. machine guns (or six .50-cal.) plus 5,200 lbs. of bombs (maximum overload) or one externally mounted torpedo Engines: Two Pratt & Whitney R-2800-41 Double Wasp radials of 2,000 hp each (takeoff power) Maximum speed: 317 mph at 14,500 ft. Cruising speed: 260 mph Range: 1,150 miles with 3,000 lbs. bomb load; 2,800 miles (maximum) Service ceiling: 23,500 ft. Span: 65 ft. 0 in. Length: 58 ft. 3 in. Height: 19 ft. 10 in. Weight: 34,000 lbs. (maximum) Crew: Seven Serial numbers: 41-17544 to 41-18184