With a French Air Force requirement to replace the Douglas C-47 and Amiot AAC-1 Bréguet started development of the Breguet 890 as a medium-capacity military transport. The commercial transport prototype designated the Bréguet 890H Mercure was an all-metal cantilever high-wing monoplane powered by two Bristol Hercules radial engines. It had a retractable tricycle landing gear and, advanced for its day, a swing tail to allow access (using a loading ramp) into the fuselage for heavy equipment and vehicles. A military prototype was also built under the designation Bréguet 891R Mars, it retained the swing tail but had provision for 20 paratroopers and was powered by two Gnome-Rhône 14R-200 radial engines. The Mars had parachute doors on each side of the fuselage, a floor chute for dropping containers and also a towing hook for a glider.
