Design and development of the Douglas DC-7 were prompted by American Airlines, which was seeking an aircraft superior in performance to the Lockheed Super Constellation being used by TWA. To meet the requirement of American Airlines it was decided to develop an improved version of the DC-6B using Wright Turbo-Compound engines, each of which had three exhaust-driven turbochargers giving some 20 per cent more output than the standard unit powerplant. Originally assigned to the civilian version of the C-74 Globemaster (which did not proceed) ‘DC-7’ was later used for Wright R-3350-powered derivatives of the DC-6, but those were completely different airplanes. American Airlines produced up-front funding for 25 new airliners, enabling Douglas to invest in its own Wright R-3350 Turbo Compound-powered airliner, the DC-7. The initial DC-7 was a direct development of the DC-6B, with the fuselage lengthened by 3 ft 4in to permit the inclusion of one additional row of seats. With the 2424kW R-3350 Turbo Compounds, gross weight went up to 15,200lb / 6895kg and required some strengthening of the landing gear structure. There were also some minor changes in detail, but externally the DC-7 appeared little different from the DC-6B. One hundred and five DC-7s were built, followed by 112 DC-7Bs, the latter having only minor improvements. In the DC-7B, the engine nacelles were extended further aft to permit the installation of saddle tanks within the rear of the nacelles, made of the new metal titanium. The additional fuel capacity enabled Pan American Airlines to initiate non-stop London-New York service with the DC-7B on 13 June 1955. The fuel capacity was marginal for North Atlantic services. With a full load and normal headwinds, DC-7Bs which were used to operate the east-to-west service, frequently had to divert for a refuelling stop. Douglas set about the task of developing a version of the DC-7B with greater range. The third version was designated DC-7C and had, therefore, increased span to provide for greater fuel capacity. This was achieved by inserting a new parallel-chord wing section between the fuselage and the inboard engine nacelles, which had the added advantage of improving the cabin environment by reducing engine noise. During the development of the DC-7C, Curtiss-Wright was able to offer a further increase in engine power up to 3,700 hp and, as a result, the fuselage was lengthened by the insertion of a 1.02m plug to provide accommodation for up to 105 passengers.
DC-7C
Production of DC-7Cs totalled 120. Not only were they used on North Atlantic and Pacific Ocean services, but they also made possible non-stop scheduled operations across the continental USA, and were used also by SAS to inaugurate a Europe-to-Far East route over the North Pole. An improved DC-7D was planned, to be powered by four 4273kW Rolls-Royce Tyne turboprop engines, but the emergence of the Boeing 707 and the Douglas Company’s purpose-built DC-8 jetliner meant that this remained only as an unfulfilled project.
DC-7 Engines: 4 x Wright R-3350 Turbo-Compound, 3250 hp. Max wt: 152,000 lb. Maximum speed: 406 mph at 21,700ft. Normal cruising speed: 355mph. Range max payload: 4,605 miles. Service ceiling: 21,700 ft. Wing span: 127ft 6in. Length 112ft 3in. Height: 3lft l0in. Wing area: 1,637 sq.ft.
DC-7C Engines: 4 x Wright R-3350 Turbo-Compound, 2500kW. Maximum speed: 406 mph / 650 km/h at 21,700ft. Normal cruising speed: 355mph. Range max payload: 7400 km / 4,605 miles. Service ceiling: 21,700 ft. Wing span: 38.8 m / 127ft 6in. Length: 34.2 m / 112ft 3in. Height: 9.7 m / 3lft l0in. Wing area: 152.0 sq.m / 1,637 sq.ft. Empty weight: 35785 kg / 78893 lb Max take-off: 143,000 lb / 64865 kg. Crew: 3-5 Passengers: 48-105
The US Army Air Forces financed the building of a pressurised prototype aircraft based on the DC-4 but with the square, rather than round, windows which were to be an identifying feature of the future DC-6. The prototype, designated XC-112A, also had 2,100-hp / 1,565kW Pratt & Whitney R-2800-34 Double Wasp engines and an 81-inch extension of its fuselage. The XC-112A flew at Santa Monica on 15 February 1946.
American Airlines placed the first order for 50 examples of the new four-engined Douglas, now called DC-6 and first flown on 29 June 1946. The DC-6 was configured to transport between 52 and 86 passengers, depending upon the class of accommodation used. A total of 175 DC-6 were built. The windowless DC-6A freighter followed in 1949, powered by 1,788.5kW Double Wasps, with reinforced floor and double cargo doors. The DC-6A, a strengthened, some¬what elongated version powered by water-injection versions of the Double Wasp engine, flew on 29 September 1949. Most DC-6As were built initially as cargo-haulers but were later converted into passenger carriers by their airline users. They had a reinforced floor and cargo-loading doors. The DC-6A was 1.52m longer than the DC-6 (101 going to the USAF as C-118A transports). The term DC-6C was used to refer to aircraft in this series built from the beginning with passenger accommodation. Seventy-four aircraft of the DC-6A/DC-6C type were built, the last being delivered in 1959. The DC-6B flew on 2 February 1951, a passenger ship lacking the floor and cargo door of its immediate predecessor. Improved 2,500-hp Double Wasp engines with paddle-blade propellers powered the DC-6B. With 288 examples delivered between 1951 and 1958, the DC-6B was the most numerous of variants in the DC-6 series, 704 of which were delivered in all and was put into service on 29 April 1951, by American, Panagra and Braniff, among others.
The DC-6B, with accommodation for 54-102 passengers, first flew on 2 February 1951 and also had the longer fuselage. American Airlines introduced DC-6B on its US transcontinental services on 29 April 1951. The US Navy was the first military customer to order a DC-6 variant in some numbers, acquiring 65 DC-6As in the late 1940s and early 1950s. These were designated R6D-1 and VIP/staff transport examples were called R6D-1Z. The single C-118 (length 100ft 7 in) is V.I.P. transport.
R6D-1
After the Navy, the US Air Force acquired 101 DC-6A aeroplanes, designated C-118A, and employed them on MATS’ worldwide routes. These aircraft could carry up to 27,000 lb of cargo or 81 fully-armed troops. In 1962, the two Naval variants were redesignated C-118B and VC-118B and 40 of them were transferred to the USAF.
Regularly scheduled operations of the commercial passenger DC-6 continued until 1967 and many of the DC-6 series were later converted to freighters.
XC-112A Engines: 4 x Pratt & Whitney R-2800-34 Double Wasp, 2,100-hp. Wing span: 117 ft 6in. Wing area: 1,463 sq.ft. Length: 100 ft 7in. Height: 29ft 1 in. Empty weight: 53,623 lb. Max take-off weight: 97,2001b. ROC: 900 fpm. Cruise: 328mph. Service ceiling: 29,000ft.
DC-6 Engines: 4 x Pratt & Whitney R-2800-34 Double Wasp, 2,100-hp. Wing span: 117 ft 6in. Wing area: 1,463 sq.ft. Length: 100 ft 7in. Height: 29ft 1 in. Empty weight: 53,623 lb. Max take-off weight: 97,2001b. ROC: 900 fpm. Cruise: 328mph. Service ceiling: 29,000ft.
DC-6A Engines: 4 x Pratt & Whitney R-2800 Double Wasp.
DC-6B Power: 4 x Pratt & Whitney R-2800 Double Wasp radials, 2400 hp. Max speed: 356 mph @ 20,000 ft. Span: 117 ft 6 in. Length: 100 ft 7 in. MAUW: 97,200 lbs. Range: 3860 mile. Cruise: 328mph. Pax cap: 107.
DC-6BF Engines: 4 x Pratt & Whitney R-2800-CB Double Wasp, 2400 hp. Wing span: 117 ft 6 in. Length: 103 ft 6 in. Height: 28 ft 6 in. MTOW: 103,800 lb. Empty wt: 56,000 lb. Cruise: 225 kt.
C-118 Length: 100 ft 7 in
C-118A Payload: 27,000 lb or 81 fully-armed troops.
Designed at Douglas Aircraft Company’s El Segundo facility, the Douglas DC-5 was developed as a 16/22-passenger commercial transport for local service operations out of smaller airports. The DC-5 was a high-wing monoplane and featured the then relatively novel tricycle-type landing gear. With a design gross weight of 8391kg, the DC-5 was offered with either Pratt & Whitney R-1690 or Wright Cyclone radial engines. The prototype, powered by two 850hp Wright GR-1820-F62 Cyclones, flew for the first time on 20 February 1939, piloted by Carl Cover. Orders were placed by KLM (four aircraft), Pennsylvania Central Airways (six) and SCADTA of Columbia (two), but the programme was overtaken by the war and only the KLM aircraft were delivered. Although intended for service in Europe, two went first to the Netherlands West Indies to link Curacao and Surinam and the other two to Batavia in the Netherlands East Indies. All four were used to evacuate civilians from Java to Australia in 1942 and one, damaged at Kemajoran Airport, Batavia, on 9 February 1942, was captured by the Japanese and extensively test-flown at Tachikawa Air Force Base. The three surviving DC-5s were operated in Australia by the Allied Directorate of Air Transport and were given the USAAF designation C-110.
DC-5 VH-ARD at Essendon January 1948 just after purchase from Australian National Airways.
Still in one piece at Haifa (although engine-less) was Douglas DC-5, VH-ARD, carrying New Holland Airways (Sydney) insignia. On the nose was the name “Bali Clipper”.
VH-ARD refuels at Cloncurry Qld during 1948 on the between Sydney and Darwin.
The earliest DC-5 military operations, however, were by the US Navy which had ordered seven examples in 1939. Three were R3D-1 16-seat personnel transports, the first of which crashed before delivery, and four were R3D-2 aircraft for the US Marine Corps with 1000hp R-1820-44 engines, a large sliding cargo door, and bucket seats for 22 paratroops. The prototype, after certification and development flying had been completed, was sold with a 16-seat executive interior to William E. Boeing, and was later impressed for US Navy use as the sole R3D-3.
Engine: 2 x 850hp Wright GR-1820-F62 radial Max take-off weight: 9072 kg / 20000 lb Empty weight: 6202 kg / 13673 lb Wingspan: 23.77 m / 77 ft 12 in Length: 19.05 m / 62 ft 6 in Height: 6.05 m / 19 ft 10 in Wing area: 76.55 sq.m / 823.98 sq ft Max. speed: 356 km/h / 221 mph Cruise speed: 325 km/h / 202 mph Ceiling: 7225 m / 23700 ft Range: 2575 km / 1600 miles
In response to the requirements of five major US airlines, Douglas designed and built the large 52-passenger DC-4, which made its first flight on 7 June 1938. This type was not put into production; instead 61 smaller unpressurised development were ordered by American, Eastern and United Air Lines. This, too, bore the designation DC-4 and the original aeroplane became the DC-4E.
DC-4 prototype
The DC 4 actually saw its first service as the wartime C 54 Skyrnaster (first flight 14 February 1942) when all 24 DC-4A built were taken by the armed forces (designated R5D Skymaster by the Navy).
The DC-4 had a retractable nosewheel undercarriage and was powered by four 820-1,080kW Pratt & Whitney Twin Wasps. It was a long-range heavy logistic transport with a payload of up to 9,980kg. A total of 207 C-54A were built, followed by increased-capacity C-54B, similar C-54D with Pratt & Whitney R-2000-11 radials, C-54E with convertible cargo/passenger interiors, and C-54G with new engines. Nine hundred and fifty-two Skymasters were completed for the USAAF and 211 for the US Navy. The C 54D-15DC (USAAF variant of the DC 4, with the DC suffix indicating Douglas Chicago) with four 1,200 hp Pratt and Whitney R2000 7 radials, was operational for the last year of WW2. USAAF C¬54s were allocated to the USN in July 1945; 92 so transferred. The C 54Q had R2000 11 engines. After the war Douglas built 79 civil DC-4-1009 and many of the military aircraft became available for airline operation – mostly with 44 seats but later with as many as 86. On 7 March 1946 American Airlines was first to introduce DC-4 on US domestic services, between New York and Los Angeles. However in October 1945 American Overseas Airlines had introduced DC-4 on North Atlantic services.
From it were developed the larger DC 6 and DC 7 series the Merlin engined Canadair C 4 and the Aviation Traders Carvair nose loading vehicle transport.
One, the VC-54C-DO Sacred Cow, served as President Roosevelt’s special aircraft and a C-54B-1-DO was used by Prime Minister Winston Churchill.
During the first years of the Berlin Airlift corridors, the pilots had to be wary about mock attacks by Soviet MiG fighters or near misses. The mutual mistrust inevitably caused a number of incidents. In April 1952 an Air France DC-4 was shot-up in one of the Airlift corridors by two Russian MiG-15a. A stewardess and two passengers were seriously injured.
A C-54 made the Berlin Airlift’s last flight on 30 September 1949.
C-54 Skymaster
The 1956 R5D2-2 radar and radio research aircraft in the US Navy featured a retractable mast with instruments.
R5D2-2
When production ceased in 1947, 1,242 had been built, of which hundreds served to re-equip civil airlines during the first postwar years.
In 1963 the Peruvian Air Force bought three DC-4B’s from US dealer Aircraft Corp of Charlotte, NC. Two for passenger transport and the third for use by Peru’s president.
DC 4 Engines: 4 x Pratt & Whitney R 2000 SD13G Twin Wasp, 1,450 hp. Wing span: 117 ft 6 in (35.80 m). Length: 93 ft 11 in (28,63 m). Gross weight: 73,000 lb (33,112 kg). Typical cruising speed: 204 mph (328 kph) at 10,000 ft (3,050 m). Accommodation: Crew of 5 plus 44 86 passengers. Typical range: 2,140 miles (3,444 km) with max payload at 201 mph (323 kph).
DC 4 Engines: 4 x P&W R-2000-25, 1065kW Max take-off weight: 33140 kg / 73062 lb Empty weight: 20000 kg / 44093 lb Wingspan: 35.8 m / 117 ft 5 in Length: 28.6 m / 93 ft 10 in Height: 8.4 m / 27 ft 7 in Wing area: 136.0 sq.m / 1463.89 sq ft Max. speed: 450 km/h / 280 mph Cruise speed: 365 km/h / 227 mph Ceiling: 6900 m / 22650 ft Range w/max.fuel: 6000 km / 3728 miles Range w/max.payload: 2200 km / 1367 miles Crew: 4 Passengers: 40-44
Douglas C 54 B Skymaster Engine : 4 x Pratt&Whitney R-2000-7, 1332 hp Length : 93.93 ft / 28.63 m Height : 27.526 ft / 8.39 m Wingspan : 117.487 ft / 35.81 m Wing area : 1462.935 sq.ft / 135.91 sq.m Max take off weight : 73012.0 lb / 33112.0 kg Weight empty : 38206.0 lb / 17327.0 kg Max. speed : 238 kt / 441 km/h Cruising speed : 208 kt / 385 km/h Service ceiling : 21998 ft / 6705 m Cruising altitude : 15207 ft / 4635 m Wing load : 50.02 lb/sq.ft / 244.0 kg/sq.m Range : 3389 nm / 6276 km
C-54M Skymaster Engines: 4x Pratt & Whitney R2000-11, 1,350 h.p. Wingspan: 117 ft. 6 in. Length: 93 ft. 10 in. Loaded weight: 73,000 lb Max. speed: 274 m.p.h. Ceiling: 22,500 ft. Typical range: 1,500 miles at 220 mph at 10,000 ft. Crew: 6 Capacity: 50 passengers, 30 stretchers or cargo.
C 54D-15DC Engines: 4 x Pratt and Whitney R2000 7, 1,200 hp.
The DC-3 resulted from American Airlines’ requirement for a sleeper aircraft for its US transcontinental route. The DC-2 fuselage was too small for this, so, reluctantly, in the autumn of 1934 Douglas agreed to build the DST (Douglas Sleeper Transport) as an enlarged DC-2, with lengthened fuselage, increased span and, an increase of 66cm in fuselage width – allowing up to 28 seats or 14 sleeping berths. The prototype DST, with 633.4-745kW Wright Cyclone SGR-1820 engines, made its first flight on 17 December 1935. The type entered service with American Airlines on 25 June 1936 over the New York-Chicago route, with transcontinental sleeper services starting on 18 September. The DC-3/DST soon proved itself and orders grew rapidly, with KLM becoming the first operator outside the US.
The first military version, the C 39, was an odd mixture of the new wing mated with the small DC 2 body. Similar aircraft procured in smaller numbers were the C 38 personnel trans¬port with Cyclones and the corresponding C-41 with Twin Wasps. Discounting about four civil DC 3s sold as VIP transports to overseas air forces, there was no true military DC 3 until October 1941, when deliveries began from Santa Monica of the C 53 Skytrooper. This simple conversion of the DC 3 had a wooden floor, fixed aluminium seats for 28 troops, and a glider towing cleat. Some were later supplied to the RAF as the Dakota II, and the US Navy and Marines as the R4D 3, and subsequent versions included the C 53B, C and D.
The main military type, put into large scale production in late 1941 at Santa Monica, Tulsa and Oklahoma City, was the C 47 Skytrain. This had been designed earlier in 1941 hence the earlier type number as an all purpose military transport with strong freight floor, large double doors, tie down fittings and folding wooden troop seats. The engine chosen was the 1200 hp R 1830 92 Twin Wasp. A first batch of 953 was followed in 1942 43 by 4991 C 47A with 24 volt electrics, and in 1943 by 3108 C 47B for high airfields (especially in India and China) with R 1830 90C engines with two stage blowers. Named Skytrain by all US forces, and designated R4D by the Navy, some 1200 C 47, 47A and 47B were supplied to the RAF under lend lease as the Dakota I, III and IV, respectively. Douglas also built 133 TC 47B trainers (R4D 7) with navigation classroom interiors, and one C 47C twin float amphibian version. The U.S. Navy version is designated R4D; but by 1955 most of these had been modified into R4D-8s, with more powerful engines, more swept wings with tips, taller squared-off fin and rudder with long dorsal fin, and room for up to 38 passengers.
C-47D
The single C 47C amphibious floatplane was a 1943 conversion of a C 47A Skytrain intended to increase the type’s versatility.
The sole 1943 XC-47C, 42-5671, had Edo amphibious floats with nose-wheels in addition to wheels under the steps, and each housed a 300 gal fuel tank.
Other oddballs included the XCG 17 glider converted from a production C 47A, and the unique DC 2½ flown out of China in an emergency with one DC 3 wing and one DC 2 wing, the original having been damaged beyond immediate repair. The glider was outstandingly successful, carrying 40 troops, towing at 464 kph (288 mph) behind a C 54 and landing at only 56 km/h (35 mph), but only one was built.
Wartime impressed civil DC 3s included the C 48 (R 1830) with civil furnishing (some were DST sleeper transports), C 49 (R 1820) usually with cargo floor and astrodome, C 50 (R 1820), C 51 (R 1820) for paratroops, C 52 (R 1830) taken over on the civil production line and completed as paratroop transports, C 68 (R 1830) previously the DC 3A late 1930s civil type, and C 84 (R 1820) previously the DC 3B. In 1945 17 purpose built VIP transports were delivered, designated C 117A. The DC-3/DST was operated as the C-38 transport.
In 1940 the Japanese navy introduced the Type 0 transport, a Showa built version of the 21 passenger DC 3.
On 21 February 1942, some 25 Douglas DC-3 aircraft built under Japanese licence but bearing US national insignia, appeared over the city of Kupang on the Portuguese-owned Pacific island of Timor and dropped 250 troops from an altitude of only 300 ft. this was the first airborne operation carried out by the DC-3.
Operation Husky, the Allied invasion of Sicily beginning 10 July 1943, involved 400 Dakota C-47 transport aircraft and 170 Waco CG-4A cargo gliders. The operation verged on failure. Ninety-seven of the British and US gliders released from their towropes too early plunged into the sea, and another 24 were reported missing: only 12 of the gliders, all British, landed in the target zone. Then strong anti-aircraft fire confused the paratroops in the Dakotas, so they jumped too soon and were scattered over almost 60 miles. Six of the Dakotas were shot down, and only 73 British paratroops reached their target, the Ponte Grande bridge.
In mid-June 1943, for the first time, a Dakota FD900 of RAF Transport Command landed in Prestwick, Scotland, towing a glider. The two planes had taken off twenty-four hours earlier from Dorval (Montreal). Piloted by Sqn.Ldrs. Seys and Gobel, the Waco CG-4A had been built in a New York piano factory, and carried a full load of vaccine and radio and engine parts for the Soviet Union.
Accomplishments of the DC 3 in the Second World War include almost 1000 crossed the Channel on the night of D Day, June 6, 1944, many towing gliders, while in China a C 47 took off at a high altitude strip with 75 evacuees on board. Total wartime output by the US (almost all Douglas) was 10123.
In 1949 Douglas built two prototypes of a much improved Super DC 3, aimed chiefly at the airlines, with 1475 hp R 1820 C9HE engines and greatly altered airframe. Few, were sold, the main customers being the US Navy/Marines (R4D 8) and Air Force (C-117D).
Circa 1949-50, British European Airways Dakotas received cockpit and cabin upgrades and become known as the Pioneer in passenger service and Pioneer Leopard for cargo.
In February 1938 Mitsui in Japan acquired a licence to build the DC 3, on the secret orders of the Japanese navy. During 1939 45 the Japanese companies Showa and Nakajima respectively delivered 416 and 71 of the L2D 1 to L2D 4 versions, with 1300 hp Kinsei engines and cockpit windows extending much further aft than in the US aircraft. These machines received the Allied code name ‘Tabby’.
Lisunov Li-2
Much greater licence production was undertaken in the Soviet Union. Under Boris Lisunov, who had studied the DC 3 at Santa Monica, the Li 2 version considerably altered incorporating 1293 changes, and with entrance on the right and was in full production during 1939 43, about 3500 being built. The Li-2 used various engines, including the ASh-621R driving SISh-21 propellors, or AV-7N or AV-161 engines. Originally powered by 671kW Shvetsov M-62 radials in the PS-84 first version, but later fitted with uprated Shvetsov ASh-62 radials, most had the M 621R engine, and many had a gun turret behind the flight deck. Some were used as bombers with four 250kg bombs under the centre section and six light bombs on the outer wings.
Postwar Allied reporting name was ‘Cab’, this also covering the 707 lend lease C 47A and B which reached the Soviet Union in 1942 43. The Li-2 was designated PS-84 in Aeroflot service. Production comprised a number of variants, some of them armed with turreted armament; the Li-2G freighter, Li-2P personnel transport, Li-2PG convertible model and the Li-2V high-altitude model are best known of the variants.
The Yugoslav Air Force operated at least 11 Li-2s between 1945 and 1959. After the deterioratiom of relations between the Soviet Union and Yugoslavia in 1948, spare parts became difficult to obtain, and so ten aircraft were re-engined with Pratt & Whitney R-1830-900 engines and Hamilton Standard propellers from 1953 onwards. These aircraft were unofficially designated Li-3 by the Yugoslav Air Force. All Li-3s were on strengrh of the 111 ppa (transport regiment) at Zagreb. At least five of them seem to have been re-serialled from the four-digit 70xx series to the five-digit 711xx series, probably in late 1969. Shortly afterwards all Li-3s may have been withdrawn from use.
Lisunov Li-3
The most dramatic of all conversions has been the various series of AC 47 night interdiction gunships usually armed with three 7.62 mm (0.30 in) General Electric Miniguns with no fewer than 54 000 rounds of ammunition. While the basic air¬craft had become familiarly called the ‘Gooney Bird’ at least to US personnel the AC 47 was also known as ‘Puff the Magic Dragon’ or ‘Spooky’. The 25 initial conversions proved so useful in Vietnam that they spurred on the later AC 119 and AC 130 programmes.
404 C-53 variant were purchased or impressed. They were called Dakota Is and this version was powered by Pratt & Whitney R-1830-92 (1.200 hp) engines. It was primarily used as a troop transport and glider tug. A single XC-53A aircraft (42-6480), with full-span, slotted flaps and hot-air leading edge de-icing equipment.
In 1949 the Cyclone 9HE weighed less than 1400 lb and delivered nearly 1500 bhp. The first two were delivered to Douglas for installation in the new DC-3 Super. Apart from new engines, the DC-3 Super has a new tail unit and outer-wing panels, a strengthened undercarriage with complete wheel retraction, and re-arranged internal accommodation. The Cyclone 9HE engines would boost speed by 45 mph to 234 mph and maximum loaded weight increase from 25,200 lb to 27,300 lb.
In World War II the RCAF had three Dakota squadrons. In 1944, 437 was created in England and served in Northwest Europe; in that same year, 435 and 436 Squadrons were formed in India for service with the British XIV Army in Burma. Between 1943 and 1989 the RCAF and Canadian Forces (CF) Air Command employed 169 Dakotas.
The DC-3 was built in numerous versions and with a wide range of Wright Cyclone and Pratt & Whitney Twin Wasp engines ranging in power from 742 to 894kW. The aircraft were operated on wheels and skis – one even had floats (the XC-47G-DL) – and there was the XCG-17 experimental troop-carrying glider version. Original US military contracts covered 10,047 aircraft of which more than 9,500 were versions of the C-47 Skytrain with reinforced floor and double doors, and 380 C-53 Skytroopers. The US Navy ordered the DC-3 as the R4D. A wide range of military designations was given to civil aircraft impressed by the services before delivery including C-48, C-49, C-50, C-51, C-52, C-68 and C-84. Many military DC-3 were supplied to the US’s allies and the 1,900 plus supplied to the RAF were given the name Dakota – a name which has been widely used in place of the DC-3 designation.
National Airways Corporation operated three models of DC-3 and applied its own model suffixes, unique to New Zealand versions. The DC-3C was the basic internal passenger version with double rear doors on the port side of the fuselage. The DC-3C freighter retained the dual rear doors on the port side, with the exception of ZK-BKE, which was the only genuine DC-3 to serve in the fleet, having been built in 1941 for United Airlines and had starboard side doors before being called up into military service. The DC-3D, with the smaller single door of prewar DC-3, an astrodome and a wireless operator’s station, was used initially on regional services. NAC ran its DC-3 with a maximum all-up weight of 26,900 lb for landing and take-off. The DC-3C Freighter could lift a payload of 4,244 lb, the DC-3C passenger 3,344 lb and the DC3D 3,244 lb. The DC-3C Freighter was the lightest, with a fleet operating weight of 17,400 lb compared with 18,200 lb for the DC-3C and 18,400 lb for the DC-3D.
Prior to Skyliner conversion in the 1960s, they could carry up to 4,824 lb of fuel in two 168 imperial gallon tanks between the front and centre spars in the centre section. The aircraft also had two auxiliary tanks each of 167 imperial gallons between the centre and rear spars on the centre line, but these were removed in the Skyliner conversion, although provision for one remained on all but the DC-3D, which retained provision for two.
The LC 47H was a winterised C 47H. Prior to 1962, before a change in the US Navy designation system, the aircraft would have been a R4D 5L. The R4D 8s were a Super DC 3 with modified outer wing panels, longer fuselage, enlarged tailplane, tall square topped fin, fully enclosable undercarriage and powered by 2 x 9 cylinder Wright Cyclone R1820 80s of 1,475hp. Principal versions – C-47, R4D-1 and Dakota Mk I (initial model), C-47A, R4D-5 and Dakota MkIII (revised electrical system), C-47B, R4D-6 and Dakota Mk IV (high ¬altitude blowers), Lisunov Li-2 (2,000+ Soviet-built aircraft), and Nakajima/ShowaL2D “Tabby” (485 Japanese aircraft).
In 1963 Libya started its own Air Force when the US turned over two T-33 and a C-47 at Wheelus AFB.
Nakajima L2D Type 0
Basler Conversions of Wisconsin have FAA approval to fit Pratt and Whitney PT6A 67R turboprop engines driving Hartzell five-bladed propellers to DC 3s, enabling up to 42 passengers or a useful load of around 5900 kgs in the revitalised aircraft, being marketed as the Turbo 67R. The fuselage is stretched approximately 42 inches from its original length, with all-new electrics, and extended fuel storage with an additional 200 gallons of fuel carried in the engine nacelle-mounted fuel tanks.
Schafer Aircraft Modifications Inc was founded 1977, and from 1979 developed modifications for other aircraft. Included was developing a turboprop conversion and fuselage stretch for the DC-3 as DC-3-65TP Cargomaster.
The aircraft was ordered in very large numbers by the US armed forces and when production ceased in 1947, Douglas had built 10,654 examples of all civil and military variants. Nakajima and Showa in Japan built 485 (L2D) and about 2,000 had been built in the USSR as PS-84, but later redesignated Lisunov Li-2. As late as 1990 there were 3,500 Dakotas still flying world wide.
Prototype DST (Douglas Sleeper Transport) / C 38 Engines: 2 x Wright Cyclone SGR-1820, 633.4-745kW
Douglas DC-3 Engines: Two Pratt & Whitney R-1830-92, 1200 hp / 880kW Maximum speed: 237 mph (379 km/h) Maximum weight: 28,000 lb (12,600 kg) Range: 1110 miles (1776 km) Maximum passengers: 28 Span: 95 ft (28.5 m) Length: 64 ft 5 in (19.3 m) Height: 16 ft 11 in (5 m) Wing area: 987 sq ft (91.7 sq m) Crew: 2
DC 3 Engines: 2 x 900 h.p. Wright Cyclones. Length: 64.5 ft. (19.6 m.) Wing span: 95 ft. (29 m.) Weight empty: 16,290 lb. (7,390 kg.). Crew: 2. Pax cap: 21. Max cruise: 185 m.p.h. (298 km.p.h.). Ceiling: 23,000 ft. (7,000 m.). Range: 1,500 miles (2,400 km.).
NAC DC-3C Payload: 3,344 lb Operating weight: 18,200 lb Maximum all-up weight: 26,900 lb Fuel capacity: 4,824 lb / two x 168 imperial gallon tanks
NAC DC-3C Freighter Payload: 4,244 lb Operating weight: 17,400 lb Maximum all-up weight: 26,900 lb Fuel capacity: 4,824 lb / two x 168 imperial gallon tanks
NAC DC3D Payload: 3,244 lb. Operating weight: 18,400 lb Maximum all-up weight: 26,900 lb Fuel capacity: 4,824 lb / two x 168 imperial gallon tanks
C 39
C-¬41 Engines: 2 x Twin Wasps.
C 47 Skytrain / R4D / Dakota I Engines : 2 x Wright Cyclone R-1820-G202A, 1200 hp Wing Span : 95ft (28.96m) Length : 64ft 5.5in (19.65m) Height : 16ft 11in (5.16m) Range : 1,500 miles (2,414km) Speed : 229 mph (369 km/h) MTOW: 25,200 lb
C 47A Skytrain / R4D / Dakota III Engines: 2 x Pratt&Whitney R-1830-93, 1200 hp Length: 64.206 ft / 19.57 m Height: 16.929 ft / 5.16 m Wingspan: 95.013 ft / 28.96 m Wing area: 986.951 sqft / 91.69 sq.m Max take off weight: 26030.0 lb / 11805.0 kg Weight empty: 16974.1 lb / 7698.0 kg Max. speed: 199 kts / 369 km/h Cruising speed: 161 kts / 298 km/h Service ceiling: 23196 ft / 7070 m Cruising altitude: 10007 ft / 3050 m Wing load: 26.45 lb/sq.ft / 129.0 kg/sq.m Range: 1304 nm / 2415 km Crew: 3+28 Elec¬trics: 24 volt
C 47B Skytrain / R4D / Dakota IV Engines: two 1,200-hp (895-kW) Pratt & Whitney R-1830 90C Twin Wasp radial piston. Max speed: 230 mph.
C-47 Skytrain Engines: two 1,200-hp (895-kW) Pratt & Whitney R-1830-92 Twin Wasp radial Maximum speed 229 mph (368 kph) at 7,500 ft (2,290 m) Initial climb rate 1,130 ft (345 m) per minute Service ceiling 23,200 ft (7,075 m) Range 1,500 miles (2,401 km) Empty weight 16,970 lb (7,705 kg) Maximum take-off: 13290 kg (29 300 lb) (sometimes 14 080 kg, 31004 lb). Wing span 95 ft 0 in (28.90 m) Length 64 ft 5.5 in (19.63 m) Height 16 ft 11 in (5.20 m) Wing area 987.0 sq ft (91.70 sq.m) Payload: 28 troops, or 18 litters, or 10,000 lb (4,536 kg) of freight.
C-47B-35-DK Engines: two 1,000 hp Curtiss-Wright R-1820-G2 Cyclone 9 cylinder radials, or 1,200 hp Pratt & Whitney R-1830-92 twin Wasp two-row 14 cylinder radials. Wingspan: 28.96 m Length 19.66 m Height 5.17 m Cruising speed 266 km/h Ceiling 21,900 ft
TC 47B / R4D 7
C 47C Undercarriage: twin float amphibian Ex-C 47A
C-47D Engines: 2 x Pratt & Whitney R1830-90, 1,200 h.p. Wingspan: 95 ft Length: 63 ft. 9 in. Loaded weight: 30,000 lb. Max speed: 224 m.p.h. Ceiling: 24,100 ft. Typical range: 1,500 miles at 185 m.p.h. at 10,000 ft. with normal load Crew: 3 Capacity: 21 passengers
LC 47H / R4D 5L Skytrain
AC 47 Armament: 3 x 7.62 mm (0.30 in) General Electric Miniguns / 54 000 rounds
C 48 impressed civil DC 3 Engines: R 1830
C 49 impressed civil DC 3 Engines: R 1820
C 50 impressed civil DC 3 Engines: R 1820
C 51 impressed civil DC 3 Engines: R 1820
C 52 impressed civil DC 3 Engines: R 1830
XC-53A No built: 1 (42-6480)
C 53 Skytrooper / Dakota II / R4D 3 Engines: 2 x Pratt & Whitney R-1830-92, 1.200 hp
C 53B Engines: 2 x Pratt & Whitney R-1830-92, 1.200 hp
C 53C Engines: 2 x Pratt & Whitney R-1830-92, 1.200 hp
C 53D Engines: 2 x Pratt & Whitney R-1830-92, 1.200 hp
DC 3A / C 68 impressed civil DC 3 Engines: R 1830
DC 3B / C 84 impressed civil DC 3 Engines: R 1820
C 117A VIP transports 17 built
C-117A-11-KK
R4D 8 / C¬117D Engines: 2 x Wright Cyclone R 1820 C9HE, 1475 hp
XCG 17 glider – ex-C 47A Capacity: 40 troops Tow speed: 464 kph (288 mph) Landing speed: 56 km/h (35 mph) No built: 1
Basler Conversions Turbo 67R. Engines: 2 x Pratt and Whitney PT6A 67R turboprop Passengers: 42 Useful load: 5900 kgs
Lisunov Li 2 Engines: 2 x Shvetsov ASh-621R, 1000 hp Propellors: SISh-21 Wingspan: 95 ft 0 in Max speed: 225 mph
Lisunov Li 2 Engines: AV-7N
Lisunov Li 2 Engines: AV-161
Lisunov Li 2 / PS-84 Engines: 671kW Shvetsov M-62 radials
PS-84I Medevac version
Lisunov Li 2 Engines: Shvetsov ASh-62 radials
Lisunov Li 2 Engines: M 621R
Lisunov Li-2DB Long range fuel tanks.
Li-2F Aerial photography
Lisunov Li-2G Freighter
Li-2LL Flying labratory
Li-2 Metro Flying labratory
Lisunov Li-2P Passenger transport
Lisunov Li-2PG convertible
Li-2PR Glass nose
Lisunov Li-2R Survey aircraft with bulged windows.
Li-2RE Flying labratory
Li-2REO Flying labratory
Lisunov Li-2T Cargo and troop carrying Cargo door on left hand side
UChShLi-2 Navigator trainer
Li-2US Navigator trainer
Lisunov Li-2V high-altitude model Ski equipped, boosted engines.
Design require¬ment to accommodate 14 passengers resulted in the DC-2, first flown on May 11 1934. Originally developed for TWA, it entered production in 1933 with 529kW Wright SGR-1820-F3 Cyclone engines.
The first of 20 ordered by TWA flew on 11 May 1934 and deliveries started soon after. The early DC-2 were so successful that by June 1934 orders for 75 aircraft had been received from airlines in both the US and abroad. Subsequent orders were received from American Air Lines, Eastern Airlines, Pan American Airways and from numerous foreign operators – the first exported DC-2 being flown by KLM in the autumn of 1934.
By September 1935 110 had been ordered and to meet the demand Douglas was producing one aircraft every three days. In 1934 Anthony Fokker acquired exclusive European rights to sell the Douglas Transport in Europe. In addition to commercial aircraft, DC-2 were purchased by the US Navy and USAAC and others were impressed into military service during World War II to serve with the Allied forces.
Usually powered by two 710 hp Wright R¬1820 Cyclone F series engines, the DC 2 seated 12 or 14 in airline service and 14 was a typical number of equipped troops for military versions. Deliveries of the latter began in 1935 with the US Army Air Corps C 32 and C 32A (24 delivered), followed by the R2D 1 of the Navy and Marine Corps. In 1942 civil DC 2s were impressed into Army Air Force service as the C 33. The eighteen C-33 had large cargo doors. A handful of aircraft formerly operated by European airlines served with the RAF, a few including the ex Polish LOT machines having Bristol Pegasus engines.
KLM DC-2 (PH-AKL) which crashed after take-off from Croydon Air Port near London, England on December 9th, 1936 taking the life of Juan de la Cierva y Codorníu, 1st Count of la Cierva,and 14 of 16 others aboard. The dead included Arvid Lindman, a former Prime Minister of Sweden, and the Austro-Hungarian fighter ace, Ludwig Hautzmayer, who was the aircraft’s pilot at the time.
In the mid-1930’s Japan obtained rights to produce the DC-2. It was built by Nakajima for civil airline use. Only a few reached military service, receiving the allied code name ‘Tess’.
Nakajima DC-2
35 were delivered to the USAF in 1939 with the DC-2 fuselage and DC-3 wing and tail assemblies, designated C-39.
DC-2 Engines: 2 x Wright Cyclone SGR-1820-F3, 710 hp Later Engines: 2 x Wright Cyclone SGR-1820-F52, 760 hp Wingspan: 85 ft Length: 61 ft / 11.75 in Empty weight: 12,408 lb Loaded weight: 18,560 lb Max speed: 210 mph Cruise: 190 mph ROC: 1000 fpm
Engines: 2 x Wright R-1820-25, 710 bhp / 550kW Max take-off weight: 8419 kg / 18561 lb Empty weight: 5448 kg / 12011 lb Wingspan: 25.9 m / 85 ft 0 in Length: 18.9 m / 62 ft 0 in Height: 4.9 m / 16 ft 1 in Wing area: 87.2 sq.m / 938.61 sq ft Max. speed: 320 km/h / 199 mph Cruise speed: 300 km/h / 186 mph Ceiling: 6100 m / 20000 ft Range w/max.fuel: 1400 km / 870 miles Crew: 2 Passengers: 14-16
In 1931 TWA Flight 599 crashed due to the failure of a wooden strut, which was caused by water which had dissolved the glue holding the layers together. The Civil Aeronautics Board ruled passenger aircraft could no longer contain wings or structural members (such as struts and spars) made of wood. Boeing 247 production capacity was limited and they could only supply their primary contract, United Airlines. TWA wanted a similar aircraft, and asked four manufacturers to bid for construction of a three-engine, 12-seat aircraft to meet the specifications stipulated by the CAB:
All metal wings and structural members Retractable landing gear Capable of remaining in flight, even if one engine failed.
Donald Douglas was initially reluctant to participate in the invitation from TWA. He doubted there would be a market for 100 aircraft, the number of sales necessary to cover development costs. Nevertheless, he submitted a design consisting of an all-metal, low-wing, twin-engine aircraft seating 12 passengers, a crew of two and a flight attendant. The aircraft exceeded the specifications of TWA even with two engines. It was insulated against noise, heated, and fully capable of both flying and performing a controlled takeoff or landing on one engine. Only one aircraft was produced in eight months, the prototype, X223Y. It made its maiden flight on July 1, 1933, flown by Carl Cover from Santa Monica in California, and was given the model name DC-1. During a half year of testing, it performed more than 200 test flights and demonstrated its superiority versus the most used airliners at that time, the Ford and Fokker Trimotors. It was flown across the United States, making the journey in a record time of 13 hours 5 minutes.
TWA accepted the model with a few modifications (mainly increasing seating to 14 passengers and adding more powerful engines) and ordered 20 aircraft. The production model was called the Douglas DC-2. The DC-1 flew with TWA (Transcontinental and Western Air) until 1936 when Howard Hughes purchased the aircraft with a view to a world flight. Instead he used a faster Lockheed 14 for his 91 hour world circling flight. The DC-1 was sold to Lord Forbes in the United Kingdom in May 1938, who operated it for a few months before selling it in France in October 1938. It was then sold to Líneas Aéreas Postales Españolas (L.A.P.E.) in Spain in November 1938. Later operated by Iberia Airlines from July 1939 with the name Negron it lost engine power on take-off and made a wheels-up landing at Malaga, Spain in December 1940 and was damaged beyond repair and later scrapped.
Powerplant: 2× Wright Cyclone SGR-1820F 9-cylinder radial, 710 hp (522 kW) Length: 60 ft (18,28 m) Wingspan: 56 ft (17,06 m) Height: 16 ft 10 in (4.88 m) Empty weight: 11,400 lb (5,171 kg) Max takeoff weight: 17,500 lb (7,938 kg) Maximum speed: 232 mph (373 km/h) Cruise speed: 186 mph (300 km/h) Range: 930 mi (810 nm, 1,500 km) Service ceiling: 23,000 ft (7,010 m) Crew: 2 pilots and flight attendant Capacity: 12 passengers
The Douglas A3D Skywarrior originated from a US Navy requirement of 1947. An attack bomber with strategic strike capability was envisaged for the new ‘Forrestal’ class aircraft-carriers.
The design was a high-wing monoplane, with retractable tricycle landing gear, two podded turbojets beneath the wing, and a large fifteen foot internal weapons bay to accommodate up to 5443kg of varied weapons. The wings were swept back 36° and had high-aspect ratio for long range, all tail surfaces were swept, and the outer wing panels and vertical tail folded.
Lateral control is by ailerons and spoilers on the outer wings. The wings are equipped with automatic leading-edge slats outboard of the engines, slotted trailing-edge flaps, and all-moving tailplane. Sideways opening airbrakes are on each side of the rear fuselage. Provision was made for twelve 4500 lb thrust jettisonable JATO rockets mounted on the side of the rear fuselage.
The first of two prototypes made its maiden flight on 28 October 1952, powered by 3175kg Westinghouse XJ40-WET3 engines, but the failure of this engine programme meant that the 4400kg thrust Pratt & Whitney J57-P-6 powered the production A3D-1. The first of these A3D-1s flew on 16 September 1953, and deliveries to the US Navy’s VAH-1 attack squadron began on 31 March 1956.
In 1962 the designation was changed to A-3, the initial three-seat production version becoming A-3A. Five of these were modified subsequently for ECM missions under the designation EA-3A. The A-3B (previously A3D-2) which entered service in 1957 had more powerful J57-P-10 engines and an inflight-refuelling probe. A reconnaissance variant with cameras in the weapons bay was designated RA-3B (A3D-2P), and EA-3B (A3D-2Q) identified ECM aircraft with a four-man crew in the weapons bay.
The EA-3B flew for the first time on 10 December 1958 as A3D-2Q and a year later the first batch of 24 production aircraft was delivered to the US Navy. Operated by VQ-1 and VQ-2 Squadrons, accidents reduced the number to about 12. The EA-3B, weighing around 33 tonne, operated regularly from aircraft carriers, fitted with hook for arrester cables and catapult. Behind the three cockpit crew members, a pressurised cabin holds four electronics specialists. The Skywarrior’s antennae are located in a wedge-shaped ventral pod under the fuselage and in the tail. Some VQ aircraft stationed at Guam had antennae on top of the fin and on either side of the cockpit.
EA-3B Seawing from VQ-2 at Rota
Apart from the American national insignia and the word NAVY, the registration number consists of one or two digits. Sometimes the identification letters PR from VQ-1 or JQ from VQ-2 were affixed, but sometimes nothing at all.
EA-3B from VQ-1
Other designations include 12 TA-3B (A3D-2T) trainers for radar operators, one VA-3B (A3D-2Z) executive transport, and the final variants in front-line US Navy service were KA-3B inflight-refuelling tankers and 30 EKA-3B tanker/counter-measures/strike aircraft. Skywarrior variants serving included TA-3B crew trainers, EKA-3B early-warning ‘aggressor’ trainers, and KA-3B tankers with Squadrons VAQ-33 at Key West and VAQ-34 at NAS Point Mugu, together with an NA-3B test aircraft operated by the Naval Weapons Test Center and NRA-3Bs with the Pacific Missile Test Center.
Of the 12 TA-3B Skywarrior built, three were converted to VIP transports with cabin windows in the forward fuselage.
TA-3B Skywarrior BuAer 144860 VIP transport
Douglas A3D-2 Skywarrior
An A3D-2 Skywarrior set a record takeoff weight from an aircraft carrier when it took off three times at 38,102 kg on 25 August 1959 from the USN’s newest aircraft carrier, the USS Independence, during suitability trials prior to the ship’s commissioning.
A3D-2 Skywarrior Naval attack bomber Engines: 2x Pratt & Whitney J57-P-2 turbojets, 10,000 lb. (approx.) thrust Wingspan: 72 ft. 6 in Length: 75 ft. 2 in Loaded weight: 67,000 lb Max. speed: nearly 700 m.p.h. Ceiling: 45,000 ft. Range: 1,500-2,000 miles. Crew: 3 Armament: 2 x 20 mm. tail guns.
A-3B Engine: 2 x Pratt & Whitney J57-P-10 turbojets, 4763kg / 10,500 lb each Max take-off weight: 37195 kg / 82001 lb Empty weight: 17876 kg / 39410 lb Wingspan: 22.10 m / 72 ft 6 in Length: 23.27 m / 76 ft 4 in Height: 6.95 m / 22 ft 10 in Wing area: 75.43 sq.m / 811.92 sq ft Max. speed: 982 km/h / 610 mph Cruise speed: 837 km/h / 520 mph Ceiling: 12495 m / 41,000 ft Range: 1690 km / 1050 miles Armament: 2 x 20mm rear-firing cannon, 5500kg / 12,000 lb of bombs
In 1936 Douglas began its Model 7 as a light attack bomber as a private venture, produced to the order of the French government. Begun by Jack Northrop and completed by Ed Heinmann, after considerable refinement this flew on 26 October 1938 as the Model 7B private-venture prototype with 1,100-hp (820-kW) Pratt & Whitney R-1830 radials. The type was maneuverable and fast, and soon elicited a French order for 100 somewhat revised DB-7s.
The first production DB-7 flew on 17 August 1939. When France fell the undelivered aircraft outstanding from French contracts were taken over by the British government and given the name Boston. Only 60 were delivered, and 20 more passed to Great Britain.
Further French orders covered 100 DB-7As and 481 DB-7Bs. Most of these served with the Royal Air Force as Havoc Mk II night fighters and Boston Mk II bombers respectively. Later Bostons were patterned on A-20 aircraft for the US Army Air Forces, and served mainly over North-West Europe. As delivered to the RAF from the French contracts, the Boston I was powered by two Pratt & Whitney R-1830-S3G-4G engines. It was used mainly for training duties, although some were converted for night fighting and given the British name Havoc. The A-20 was the first of the series built to a US Army specification and was powered by two 1,112kW Wright R-2600-7 Cyclone engines with exhaust-driven turbo-superchargers. It was fitted with American armament and equipment. As the Boston II for the RAF, the A-20 had R-2600-A5B engines and British armament. Those converted into night fighters became Havocs each with a lengthened nose fitted with 12 forward-firing 7.62mm guns, AI radar and other special equipment depending on the sub-variant – one carried a high-power searchlight in the nose. As an intruder it carried a crew of three and full armament and bombs. The A-20A for the USAAC/USAAF was powered by two 1,192kW Wright R-2600-11 engines with integral two-speed superchargers. The A-20B was an experimental development of the A-20A, armed with two 12.7mm guns firing forward, one 12.7mm upper flexible gun, one 7.62mm lower flexible gun, and one 7.62mm gun in the tail of each engine nacelle, firing aft. Nacelle guns were remotely controlled by a foot trigger in the rear compartment. The A-20C was powered by two similarly rated R-2600-23 engines. Armament comprised four fixed guns (two on each side of the transparent nose), two on a flexible mounting in the rear cockpit, and one in the lower rear-firing position – all 7.62mm (A20G) or 7.69mm (British Boston Ill). Ejector-type exhaust stacks replaced the collector rings used on the earlier models and range was increased by the addition of a self-sealing fuel tank in the forward and rear bomb-bay compartments. Provision was also made on some aircraft to carry a 900kg naval torpedo.
Douglas A-20 Havocs, 1939
The observer (not only bomb aimer) was completely cut off from the pilot. Because of this the gunner had at the back a duplicate joystick. On high level operations a Vickers K gun was mounted in the rear entrance hatch. A camera was also carried mounted in this hatch.
It may be of interest that the very first operation carried out by the USA against Europe was on July 4, 1942, when six of their Bostons were led by six 226 Squadron Bostons.
A-20 Havoc
The Boston III was powered by R-2600-A5B engines and carried a crew of four as a bomber. The Boston IIIA was similar but built by Boeing. Some Boston III/IIIA were fitted as intruders with four 20mm cannon under the forward fuselage, four 7.69mm guns in the nose, and two 7.69mm guns in the upper flexible position.
Following the experimental XA-20E, with a 37mm nose cannon and General Electric turrets, the A-20G appeared. This was similar to the A-20C except that the transparent bombardier nose was replaced by a solid nose fitted (in earlier versions) with four 20mm cannon and two 12.7mm machine-guns and ultimately with six 12.7mm guns. A few also had a single 12.7mm upper flexible gun, but this was soon replaced by a power-driven turret armed with two 12.7mm guns. Thicker armour for increased crew protection on ground-attack missions was also added. The A-20H was powered by two 1,267kW R-2600-29 engines and incorporated minor improvements. The A-20J was identical to the later version of the A-20G except that the attack nose was replaced by a moulded-plastic bombardier’s nose incorporating bombing controls and flight navigation instruments. One in ten A-20G were completed as A-20J to serve as squadron lead planes. Armament consisted of two 12.7mm machine-guns (one in each side of the transparent nose), two in the power-operated dorsal turret and one in the lower rear firing position. The A-20K was identical to the A-20H except that the attack nose was replaced by a bombardier’s nose, as with the A-20J. The British Boston V was similar. Special US versions of the A-20 appeared as the P-70 night fighter with R-2600-11 engines and armed with four 20mm cannon mounted in a fairing beneath the fuselage bomb bay; the P-70A conversion of the A-20G with R-2600-23 engines and six 12.7mm machine-guns in a solid nose and dorsal and lower guns; the P-70B development of the P-70A for training, with six 12.7mm ‘package’ guns and special radar (converted A-20G/J); the F-3A night photographic-reconnaissance conversion of the A-20J/K; and BD-1/2 target tugs for the US Navy.
Production for the RAF, USAAF, US Navy and Russia ceased on 20 September 1944 after 7,478 had been built (7008 by Douglas and 380 by Boeing). Russia received twice as many as the RAF and only some 800 less than the US Army.
Principal versions DB-7 (R-1830) DB-7A (Wright R-2600, many passed to Great Britain as Havoc Mk Is) DB-7B (revised systems and larger vertical tail) Boston Mk I (taken-over DB-7s) Boston Mk II (taken¬over DB-7Bs converted to Havoc Mk I) Boston Mk III (British DB-7Bs) Boston Mk IIIA (200 Lend-Lease A-20Cs with British equip¬ment) Boston Mk IV (169 Lend-Lease A-20Js with heavier fixed armament) Boston Mk V (90 Lend-Lease A-20Ks with more power). P-70 version of the A-20 became an early night fighter.
DB-7B / Boston Mk III Engines: two 1,500-hp (1,119-kW) Wright R-2600-A5B Cyclone radial Maximum speed 311 mph (500 km/h) at sea level Initial climb rate 2,000 ft (610 m) per minute Service ceiling 25,170 ft (7,670 m) Range 525 miles (845 km) Empty weights: 15,051 lb (6,827 kg) Maximum take-off 21,580 lb (9,790 kg) Wingspan 61 ft 4 in (18.69 m) Length 47 ft 3 in (14.40 m) Height 18 ft 1 in (5.51 m) Wing area 464.0 sq ft (43.11 sq.m) Armament: seven 0.303-in (7.7-mm) machine guns, and up to 2,000 lb (907 kg) of bombs.
A-20G Havoc Engines: 2 x Wright R-2600-23 Cyclone 14, 1578 hp / 1193kW Max take-off weight: 12338 kg / 27201 lb Empty weight: 7250 kg / 15984 lb Wingspan: 18.69 m / 61 ft 4 in Length: 14.63 m / 47 ft 12 in Height: 5.36 m / 17 ft 7 in Wing area: 43.20 sq.m / 465.00 sq ft Wing loading: 58.63 lb/sq.ft / 286.00 kg/sq.m Max. speed: 275 kts / 510 km/h / 317 mph Cruise speed: 200 kts / 370 km/h / 230 mph Service ceiling : 25000 ft / 7620 m Range: 891 nm / 1650 km / 1025 miles Crew: 4 Armament: 9 x 12.7mm 50 MG (12,7mm) machine-guns, 1800kg of bombs
The Douglas company’s initial essay into high-speed research aircraft was the D-558-1 Skystreak which first flew on 14 April 1947 at the beginning of a programme to investigate free-flight air load measurements of the type that were then unobtainable in wing tunnel tests. The D-558-1 was fitted with a pressure-recording system connected to 400 points on the aeroplane’s surface, and powered by a 4,000-lb (1814-kg) Allison J35-A-23 turbojet yielded invaluable research data. The type was later re-engined with the 5000-lb (2 268-kg) thrust J35-A-11, and secured two world air speed records during 1947. The Skystreak set two speed records in 1947. Pilot on the second attempt was Major Marion Carl USMC who averaged 650.92 mph in two runs over a 3 km course.
The three D-558-I Skystreaks were turbojet-powered aircraft that took off from the ground under their own power. The D-558-1 Skystreak broke sound barrier in 1948. Of the three built, the first aircraft is on display at the Naval Aviation Museum in Pensacola, Florida. The second D-558-I crashed on3 May 1948, killing NACA pilot Howard C. Lilly. The third Skystreak is owned by the Carolinas Historical Aviation Museum located at the Charlotte International Airport in North Carolina.
Developed from D-558-1 the Skystreak, the D-558-II Skyrocket (first flown 4 February 1948) was built primarily to investigate the properties of swept wings for high-speed flight. The D-558-2 Skyrocket was in essence a swept-wing version of the straight-winged D-558-1 powered by a 3000-lb (1361-kg) thrust Westinghouse J34-WE-22 turbojet supplemented by a 6000-lb (2722-kg) thrust Reaction Motors XLR-8 rocket motor. The type first flew in February 1948 and the rocket engine enabled the Skyrocket to exceed Mach 1 in October 1947 and later, on 20 November 1953, piloted by NACA test pilot A. Scott Crossfield with the turbojet removed and the rocket fuel capacity doubled, it reached Mach 2.01 (1327 mph) at a height of 65,000ft after being released from a Superfortress mother-plane. Three months earlier it had reached 83,235 ft after a similar launch. The D-558-II last flew on 12 December 1956.
D-558-2
The rocket-powered air-launched D-558-II Skyrocket became the first aircraft to exceed Mach 2. The first D-558-II is on display at the Planes of Fame Museum in Chino, California. The number two Skyrocket, the aircraft used by Scott Crossfield to first break Mach 2, is on display at the National Air and Space Museum in Washington DC. The last D-558-II is displayed on a pedestal at Antelope Valley College, Lancaster, California.
