Douglas Dakota

The roots of the Dakota can be traced back to the Douglas DC-2 commercial airliner which was converted for use with the United States Army. So when on the 17th December 1935 the DC-3 made its first flight, its improved performance and increased capacity was naturally going to be of interest to the United States Army. Therefore Douglas were contacted by the United States Army with a list of requirements that needed to be met so the new aircraft could be used for a number of roles.

Many of the changes to the aircraft's design that the United States Army had requested, which included a larger cargo door at the rear and strengthening of the cabin floor so the aircraft could hold heavy cargo, had in fact already been done by Douglas as they were working on a prototype cargo aircraft designated C-41. This derived from the C-39 which was a mixture of the DC-2 and DC-3 with a pair of 1,200-hp Pratt & Whitney Twin Wasp engines. This would place Douglas in a good position so that when the United States Army placed orders for their new aircraft during 1940, which would be known as the C-47 Skytrain by the United States Armed Forces and as the Dakota by the Royal Air Force, based on the DC-3, the company was ready to meet the specifications required.

The biggest problem facing Douglas was production of the aircraft as they were currently committed to building another of their aircraft, the A-20 Havoc, to fulfil European contracts and as a result their Santa Monica, California factory was at capacity. This led to a new factory being built at Long Beach, California where the Dakota would be produced. The first of these new aircraft were designated C-47, which were named Dakota Mk I by the Royal Air Force, and the first one flew on the 23rd December 1941. An all-metal light alloy constructed aircraft the basic design of the Dakota was virtually untouched during its manufacture.

Housing a crew of three, pilot, co-pilot/navigator and wireless operator, the Dakota would be powered by a pair of supercharged Pratt & Whitney B-1830-92 Twin Wasp engines, featured semi-retractable landing gear and set low on the fuselage was its cantilever wing. The configuration of the almost circular cabin depended on the required use of the aircraft. As a basic cargo carrier its maximum load was 6,000lb. In its role as a transport aircraft up to 28 troops could be accommodated or for medical use 3 medics and 18 stretchers could be taken. Underneath the aircraft there was space for two 3 blade propellers and 6 parachute pack containers.

During 1941 the United States Army Air Force started to take delivery of their first C-47s, however, as the Long Beach factory was new it would take a while to get up to speed, so initial deliveries were slow. To help increase the number of aircraft available any DC-3s either in service or almost completed for delivery to US airlines were impressed into USAAF service, whilst efforts to increase production were made. With more orders flooding in requiring thousands of the type another production line had to be established at Tulsa.

The C-47A was the next version to be produced with the main change over its predecessor was its 12-volt electrical system being replaced by a 24-volt system. These were know as Dakota Mk IIIs when in RAF service. The C-47B was to follow and these would be powered by either R-1830-90 or 90B engines which featured two-stage supercharges. The main use for this version was flying supplies from India to China which required flying over the 16,500 ft high Himalaya peaks which was known as 'The Hump'. These were known as Dakota Mk IV when used by the RAF. A small number of navigation trainers were also produced and designated TC-47B.

Eventually larger numbers of the type became available and when in mid 1942 Air Transport Command was formed by the USAAF the type would be deployed in larger numbers and would have three primary roles. Firstly in the transport role the Dakota would deliver a wide variety of supplies via airfields or parachute drop. Secondly as a troop transport and thirdly transporting casualties on their way back after dropping off men and supplies. The Dakota would be employed in two new roles whilst serving in Troop Carrier Command and Transport Command with the United States Army Air Force and Royal Air Force respectively, carrying airborne troops and as a glider tug. This would lead to a variant known as the C-53 Skytrooper, known as Daktoa Mk II when being used by the RAF, which lacked the double door and reinforced floor but could hold 28 paratroopers. Also installed with a towing cleat, which would be fitted as standard to future aircraft, it would be in these two roles that the type would be best remembered for.

Another major user of the aircraft was the United Sates Navy who used around 600 under the designation R4D serving as part of the Naval Air Transport Service and South Pacific Combat Air Transport Service. The type would play a vital role supplying the United States Marine Corps as they re-took the islands located in the Pacific. The R4D would also serve in a number of other roles including the radar countermeasures R4D-4Q/5Q/6Q and the R4D-5L/6L which would normally be equipped with skis as part of its conversion for use in the winter.

During its Second World War (1939 - 1945) service the Dakota would play a key role in a number of major operations. July 1943 would see the type used as a troop transport in large numbers for the first time when over 3,500 paratroopers were dropped during Operation Husky (9th July 1943 - 17th August 1943), the invasion of Sicily. Further operations for the Dakota would see them provide supplies for the Chindits during their operations in Burma during 1943 - 44. Other operations in Burma would see the aircraft take part in the first airborne invasion on the 5th March 1944 as part of Operation Thursday. During Operation Overlord, which began on the 6th June 1944, over 1,000 Dakotas would serve as troop transport or glider tugs, and in the next 50 - 60 hours 60,000 paratroopers would arrive in Normandy courtesy of the Dakota. Three months later the aircraft would take part in Operation Market Garden (17th September 1944 - 25th September 1944) which aimed to secure a number of key bridges in the Netherlands.

One unusual variant that was considered was a floatplane version. The prototype, known as the XC-47C, would be equipped with floats containing retractable undercarriage and the ability to hold 300-US gallons of fuel. This would never reach the production stage although maintenance units with the United States Army Air Force would convert a small number of Dakotas to a similar specification for use in the Pacific. Another idea that was tried was to use a converted Dakota to fill the gap for a fast, large capacity glider to be towed by the Douglas C-54 Skymaster and using a standard airframe tests were conducted to assess the practicality of such an idea. Firstly the aircraft would make approaches and landings with both engines off, then taking-off with a small amount of power, whilst being towed by another Dakota, before switching off its engines. With the tests now finished the Dakota would have a number of modifications to it to convert it to, what would be known as, the XCG-17. Only limited conversion work could be done as the USAAF wanted any aircraft converted to gliders to be able to be returned to powered aircraft if the necessity arose. The changes to the aircraft would see the engines and propellers removed and the nacelles covered and any redundant equipment taken out. The next stage for the XCG-17 was a test programme which would show the aircraft had a glide ratio of 14:1, a stall speed of 35 mph and a 290 mph towed speed and with the ability to carry 40 paratroopers. Despite the tests on the aircraft being considered a success, the XCG-17 due to modified requirements would never enter production.

In total 10,692 Dakotas would be built with further production of licence built examples in the Soviet Union, known as Lisunov Li-2, and as the Showa (Nakajima L2D) in Japan. Unlike a number of other aircraft the end of the Second World War didn't spell the end of the Dakota as they would also see service in the decades afterwards taking part in a number of operations by the military including the Berlin Airlift (26th June 1948 – 30th September 1949), Korean War (1950 - 1953) and Vietnam War (1959 - 1975).