The Douglas A-26C Invader differed from the A-26B in having a transparent bombardier's nose in place of that version's solid gun carrying nose. This made it a more conventional medium bomber, and also made it better suited to the medium level bombing role that it was expected to perform in Europe.
At first Douglas had planned to produce both versions of the A-26 at Long Beach and at Tulsa. This plan was abandoned after Tusla had produced 205 A-26Bs and Long Beach only five A-26Cs, and each factory then concentrated on a single model. While Long Beach produced the solid-nosed A-26B, Tulsa produced the A-26C, eventually building 1,086 before production ended in the spring of 1945.
The A-26C was armed with six .50in guns carried in the wings, two in the nose, and the same pair of remote controlled turrets as the A-26B. Early aircraft had the same flush cockpit canopy as the prototype, but improvements were introduced on both models at about the same time, so the A-26C received the higher canopy and the same increases in fuel capacity as the A-26B.
The A-26C carried a crew of three, with the gunner in his enclosed compartment aft of the bomb bay and a pilot/ radio operator and bombardier/ navigator in the pilot's cockpit. The bombardier sat next to the pilot most of the time, normally only moving into the glass nose for the actual bombing run. This was partly a safety feature, for when the nose wheel failed the glass nose often suffered very heavy damage.
The two models of A-26 were expected to operate together on medium or high level bombing missions, with the glass nosed A-26Cs leading flights of A-26Bs to their targets. An initial shortage of A-26Cs meant that this role was often filled by A-20s or B-26s, although in at least one unit a small number of A-26Cs were used as bomb leaders for the older aircraft.
A number of A-26Cs were converted into night reconnaissance aircraft, initially as the FA-26C and after 1947 as the RB-26C. This version could carry a variety of different cameras, radar and other electrical devices, and had the lower turret replaced with a radome. In some aircraft the bombsight was removed from the nose and replaced with the radar equipment. The RB-26 remained in service into the Vietnam War.