The Douglas DC-5, also known as the Douglas Commercial Model 5, was designed as a twin-engine propeller aircraft with a seating capacity of 16 to 22 passengers.
Its intended use was for shorter routes compared to the Douglas DC-3 or Douglas DC-4.
Unfortunately, upon its commercial debut in 1940, numerous airlines cancelled their orders for aircraft, resulting in the production of only five civilian DC-5s.
The Douglas Aircraft Company had already shifted its focus to World War II military production, rendering the DC-5 obsolete.
Despite this, a limited number of military variants were still manufactured.
In 1938, the DC-5 was developed as a civilian airliner with a seating capacity of 16-22 individuals.
The aircraft was designed to accommodate either Pratt & Whitney R-1690 Hornet or Wright R-1820 Cyclone radial engines.
Notably, the DC-5 was the first airliner to feature a combination of shoulder wings and tricycle landing gear, a configuration that remains prevalent in modern turboprop airliners and military transport aircraft.
However, contemporary versions of this design are typically high wing, as the structure sits atop the fuselage shell rather than intersecting a significant segment.
The tricycle landing gear was a pioneering feature for transport aeroplanes, providing superior ground handling and visibility for pilots.
The aircraft’s fuselage was positioned approximately two feet above the ground, facilitating the loading of passengers and cargo compared to conventional landing gear.
Early design modifications included the addition of a 15-degree dihedral to the horizontal tail group to address a hint of aeroelasticity issues.
The DC-5 also featured a dorsal strake, initially introduced in a minimal form and later expanded to full growth on the Boeing 307.
Another significant modification was the incorporation of exhaust stacks to the engine nacelles, which was retroactively added after the series entered production.
An unusual optical illusion was applied to the prototype, with the top of the vertical stabiliser and the outline of the engine nacelles painted in a darker colour following the aircraft’s contour, creating the impression of a sleeker and smaller tail and engines.
Before the United States entered World War II, one prototype and four production aircraft were constructed.
Variants Prototype DC-5 The prototype was sold to William E. Boeing as a personal aircraft, was modified to fit 16 passenger seats. DC-5 The basic passenger version: five aircraft were built, one prototype and four production aircraft. C-110 Retroactive designation for three former Indonesian-registered KNILM aircraft that had been bought by the United States Army Air Forces for service in Australia on behalf of the Allied Directorate of Air Transport in March 1942. R3D-1 The military version of the DC-5 was built for the United States Navy as a 16-seat personnel carrier. Three were produced. One crashed at Mines Field, on June 1, 1940. Another was retired in January 1946. The third is believed to have been used briefly by General Douglas MacArthur; retired in January 1945. R3D-2 A military version of the DC-5 was built for the United States Marine Corps as a 22-seat paratrooper version, four were produced. R3D-3 The prototype, registered NC21701, was sold to the military in 1942. Withdrawn from use June 30, 1946, in the U.S. Navy Aeronautical Laboratory, Banana River, Florida. Specifications DC-5 Crew 3 Capacity 16-24 passengers Length 62 ft 2 in (18.95 m) Wingspan 78 ft (24 m) Height 19 ft 10 in (6.05 m) Wing area 824 sq ft (76.6 m2) Airfoil Root NACA 23018 Tip NACA 23012 Empty weight 13,674 lb (6,202 kg) Gross weight 20,000 lb (9,072 kg) Fuel capacity 550 US gal (460 imp gal; 2,100 L). 34 US gal (28 imp gal; 130 L) oil in two nacelle tanks Powerplant 2 × Wright GR-1820-G102A Cyclone 9-cylinder air-cooled radial piston engines, 900 hp (670 kW) each at 2,300 rpm and 6,700 ft (2,000 m) Propellers 3-bladed Hamilton-Standard Hydromatic fully feathering variable-pitch propellers Performance Maximum speed 230 mph (370 km/h, 200 kn) at 7,700 ft (2,300 m) Cruise speed 195 mph (314 km/h, 169 kn) 65% power at 10,000 ft (3,000 m) Range 1,600 mi (2,600 km, 1,400 nmi) maximum Service ceiling 23,700 ft (7,200 m) Absolute ceiling on one engine 11,400 ft (3,500 m) Rate of climb 1,585 ft/min (8.05 m/s) Wing loading 24.3 lb/sq ft (119 kg/m2) Power/mass 0.11 hp/lb (0.18 kW/kg). Sources Air Mobility Command Museum. McDonnell Douglas aircraft since 1920: Volume I-René J Francillon. San Diego Air and Space Museum Archive. The National Museum of the U.S. Air Force. Charles Daniels Photo Collection.
