The Cessna DC-6 was developed in 1929 as a four-seat version of the CW-6. This high wing aircraft was victim of the Great Depression so only about 40 of them were built. Half of them was the DC-6A version, and the other half were the DC-6B. Some these aircrafts were bought by the United States Army air Corps (USAAC) in 1942.
The DC-6A was fitted with a 300hp (224 kW) Wright R-975 Whirlwind engine. The USAAC named the armed version the UC-77.
The DC-6B had a 225hp (168 kW) Wright J-6 engine. It was called the UC-77A by the USAAC.