Douglas DC-8

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Douglas DC-8

The DC-8 is a four-engine airliner, medium and long-haul, built from 1959 to 1972 by Douglas Aircraft Company and McDonnell Douglas after the merger of the two companies. This is one of the first civilian jet aircraft and one of the emblems of the jet age.

Its first flight lasting about two hours took place May 30, 1958 Long Beach at Edwards Air Force Base in California, with onboard including Donald Douglas father and son and its entred  in the service in 1959 in the United Airlines and Delta Airlines. Against Boeing with its 707 (first real commercial success of a civil jet aircraft), Douglas had only his DC-7 propeller to conventional engines. The builder had been slow to launch its jet project and this delay caused the DC-8 came on the market in 1959: the DC-8 was nevertheless a big success at first. Subsequently, the fact that it is available in one size fuselage until 1966 was a commercial disadvantage vis-à-vis the 707, more flexible.

It was built in 556 copies in different series tailored to domestic flights, international flights or with lengthened fuselage.

Douglas DC-8-11 N8002U, San Francisco Jan 1967. Souce : Wikimedia Commons 

History : 
DC-8 Airborne Laboratory arrival at NASA Dryden
Photo from Wikimedia Commons
The DC-8 was among the 1st civil jets and was built during the period know as the era of the jet. However it was already a little behind its main competitors, namely that the first commercial jet aircraft, the De Havilland Comet, made its first flight in July 1949 and entered service in 1952. A series of crash results in the suspension of flights from Comet in 1954, when Boeing was flying his 707. the Douglas team evaluated even before the first flight of the DC-7, the feasibility of a jet airliner but in view of the Comet crashes project was more than idle. Moreover, Douglas thought of a stretched version of the DC-7D, highlighting a proven technique.
It was only a year after the first flight of
the B-707, Douglas began to study DC-8 in 1955

Military career :
If the DC-8 had no success with the military of its competitor Boeing, it was nevertheless in no less an aircraft valued for certain operations, mainly due to freight transport. Thus the Spanish air forces, Gabon, Omani, Peru, Philippines, and Thailand used this machine.

The case of France and the United States including:

The Air Force used his DC-8 as much as cargo airplane than CME platform. In the latter case there are two planes that were transformed under the designation Sarigue until their withdrawal in the early twenty-first century. One of them is exposed on the tarmac of the Museum of Air and Space Bourget.
The US Navy on his side had recourse to a training version for electronic warfare with his one and only EC-24A, a device now out of service and stored at Davis Monthan.

DC-8-53 F-RAFE / 45570; Former french spy plane, seen here near Paris Le Bourget air & space museum at Dugny.
Photo from Wikimedia Commons

 Military operators
 French Air Force
 The Spanish Air Force
 Peruvian Air Force
 Philippine Air Force
 Thai Air Force
 NASA / US Navy

Versions :

The models of the early series had uniform hull dimensions and differed only in the choice of engines used in the maximum takeoff weights (MTOW) and in the technical details of each other.

Early series

The D.C-8 Series 10 was the 60.50 kN thrust Pratt and Whitney delivered JT3C-6 engines delivered. These machines were designed primarily for US domestic flights. The first series D.C-8-11 still possessed the wingtips with the high air resistance. These machines have been converted gradually to D.C-8-12, which also owned slats and increased to 123 tons of weight in addition to the modified wingtips. A total of 28 machines of 10 series were produced, some of which received new engines after their delivery and then were standard series 50th

The D.C-8 Series 20 was the 70.80 kN thrust Pratt and Whitney delivered JT4A-3 engines delivered. The takeoff weight increased to 125 tonnes. 34 machines were produced. The first flight of this group took place on 29 November 1958th

The D.C-8 Series of 30 was the 72.50 kN thrust Pratt and Whitney delivered JT4A-9 engines delivered. In addition, however, the fuel capacity was increased by more than 33 percent in order to serve transcontinental routes can. The first flight took place on February 21, 1959. For this purpose, the fuselage and the landing gear had to be strengthened. The first machines of this series, the D.C-8-31, their approval received on 1 February 1960, a person weighing 136 tons.

DC-8-32 of Overseas National Airways in Zurich, 1975
Photo from Wikimedia Commons
The DC-8-32 was comparative however permitted a launch mass of 140 tonnes. The D.C-8-33 had 78.40 kN supplying JT4A-11 engines, a change in the flaps that allowed for a lower fuel consumption at cruising altitude. The valves could be operated in a cruise position of 1.5 °. The chassis has been further strengthened, so that now a takeoff weight of 143 tons was possible. Later, many machines of the type were -31 and -32 to -33 rebuilt.

Douglas DC-8-42 CF-TJE of Trans Canada Airlines
at London Heathrow in 1962,
Photo from Wikimedia Commons
The D.C-8 Series 40 was the first passenger airliner ever equipped with turbofan engines that were significantly quieter and more economical compared to the previous turbojets. The smoke development was much lower. For use Rolls-Royce Conway engines came with 78.40 kN thrust. The first flight took place on 23 July 1959 the approval on 24 March 1960.

The D.C had 8-41 a takeoff weight of 136 tons, the D.C-8-42 is one of 140 tonnes.

The D.C-8-43 had the same flap change as the DC-8-33. In addition, the wings were changed, which again somewhat more fuel capacity and, above all, meant a reduction in resistance, the range increased by eight per cent and the travel speed to 10 knots increasing. The initial weight was 143 tons. These changes were incorporated in all other DC-8 grades. From the series 40 32 machines were built.

The D.C-8 Series 50 also had turbofan engines, there were Pratt and Whitney JT3D-1 with 76.10 kN thrust or JT3D-3B used with 80.60 kN thrust.
The series D.C-8-51, D.C-8-52 and D.C-8-53 differed in their starting weights of 126, 138 respectively 142 tonnes. Late versions of the D.C-8-53 had the stronger cells and kits of the freighter versions and had a launch mass of 147 tonnes. The first flight took place on 20 December 1960. 88 aircraft were built of this series.

Hong Kong Kai Tak Int'l Airport (Closed) -
VHHH, China (Hong Kong)
Photo from Wikimedia Commons
D.C-8 Series Jet Trader were freighter versions of the D.C-8-50. They had a front cargo bay with a large cargo door and a reinforced cabin floor and an underlying cabin for first 54 passengers. This arrangement was short time later substituted by a sliding device for separating the cargo hold, which made it possible to carry 25-114 passengers. The first flight took place on 29 October 1962 the approval on 29 January 1963. The first aircraft was delivered on 26 April 1963, the Trans International Airlines. There was also a variant without a cabin window of the only 15 machines were sold to United Airlines.

The D.C-8F-54 had a takeoff weight of 143 tons, while the D.C-8F-55 had a takeoff weight of 147 tons. Both types were driven by JT3D-3B engines with 80.60 kN thrust. A D.C-8-54F was rebuilt by the US Navy to replicate as EC-24 for training purposes enemy communications and radar systems.

On August 21 in 1961, broke a D.C-8-43 amid an orbital slant Departure 52,090 ft (15,877 m) to 41,088 ft (12,524 m) tallness, the sound wall. The pace of Mach 1.012 could be kept up for 16 seconds. The team skipper William Magruder, First Officer Paul Patten, flight engineer Joseph Tomich and Flight Test Engineer Richard Edwards, the D.C-8 took off from Edwards Air Force Base in California for a practice run. Information ought to be gathered on a recently developed driving edge of the wings. A North American F-100 Super Saber and Lockheed F-104, flown by Chuck Yeager, the D.C-8 went with amid the trip. These D.C-8 was the main non military personnel and the principal plane carrier achieved supersonic rate. The airplane was later conveyed to Canadian Pacific Air Lines.

After an excellent start of the series, sales ran soon depressed. Reason was the manufacturer Douglas business decision, despite the large number of variants initially offer any shortened or lengthened cabin, because the development department was busy perfectly with the development of the Douglas D.C. 9 In 1964 only 14 machines which were in turn sold a majority as cargo planes. Boeing with the 707 appeared in the cabin length adaptable and always gained greater market share.

Super Sixties

DC 8-62H at Ataturk Airport in flight
After completion of the development of the DC-9 and its first flight on February 25, 1965 Douglas finally responded in April 1965, gave the cab extension for the DC-8 with three new models known. Until the appearance of the Boeing 747 in 1970, the so-called Super Sixties were over 250 seats, the largest passenger aircraft of its time. A total of three basic versions were offered:

This is a picture of a douglas dc 8 - 60,s series and not a b767.
Photo From Wikimedia Commons
The DC-8 Series 61 based on the -53 with the same take-off weight. According smaller the range compared to the -53. To increase the capacity, the front cabin has been extended by 6 m and the rear by 5 m, giving a total length of 57 m. The cabin had to be correspondingly amplified because of the greater loads. The chassis on the other hand did not have to be extended. These machines typically framed 210 passengers - with compressed seating were also 269 passengers are transported. The first flight took place on 14 March 1966 the approval on September 2, 1966. In addition to the passenger version offered Douglas factory also "Convertible Freighter" (CF) at the cabin window, an additional reinforced cabin floor
and a cargo hatch possessed, making them either
as passenger or cargo aircraft were used. A total
of 88 machines were built, of which ten in the CF version.

Air Jamaica McDonnell Douglas DC-8-62H
Photo from Wikimedia Commons
The DC-8 Series 62 corresponded to the -53 and was designed for the long haul. Compared to the -53 the car was front and rear extended by only 1.02 m. the wing tips have been extended by one meter, so as to increase the fuel capacity and to reduce the aerodynamic drag to extend the range. At the same time the engine mounts and panels have been changed. The machine received over the -61 a slightly larger-off weight of 151.953 tons and had thus a range of 9630 kilometers with a full load. The first flight took place on 29 August 1966, the approval in April 1967. The last built machines had increased to 158.760 tons takeoff weight and were designated DC 8-62H.
In addition to the basic version as a passenger aircraft,
the windowless Nurfrachtversion ( "All Freight" or AF)
and the variant as "Convertible Freighter" (CF)
were offered factory. Douglas produced a total of 67 machines
 of the series 62, including ten as DC 8-62CF and six as DC 8-62AF.

The DC-8 Series 63 was a mixture of the long cabin of -61 with the improvements of -62. As drive served JT3D-7 engines with a thrust of 85 kN. The maximum take-off weight was 159 tons, the range with maximum payload 7600 km. The first flight took place on 10 April 1967, the approval on June 30, 1967. The Series 63 was the factory as all-cargo (AF) and offered as a combi aircraft (CF). A special version was ordered only by Eastern Air Lines DC-8-63PF who possessed the reinforced cabin floor of the cargo version, but no cargo hatch on the main deck. Eastern chose this version in order to also transport soldiers with field pack on military mission flights can. A total of 107 machines of 63 series were produced, including 53 as a DC 8-63CF, seven as DC 8-63AF and six as DC 8-63PF.
The last machine of the type DC-8-63 left on May 13, 1972, the assembly hall. Immediately thereafter, the production facilities were used for the production of McDonnell Douglas DC-10th

Super Seventies

With the beginning of the 1970s, discussions began about the increasing air traffic, particularly over the growing noise pollution from the airport residents. The DC-8 types of series 61 to 63 were the loudest of all jet aircraft. With the noisy DC-8 equipment they had some airports may no longer fly: Over time, the noise emissions of the airline became a problem.

It was therefore requested the early 1970s by some airlines at McDonnell Douglas, if not allowed to install quieter engines on the DC-8 engine. First company huddled with solutions to reduce noise emissions, so-called hush kits on the market, but did not meet all expectations. Finally, CFM International brought to the CFM56 engine, a variant to the game, which could close neither Boeing McDonnell Douglas yet. The development began in the late 1970s and led to the Super Seventies. None of the Super-Seventies-machine is newly produced, but they are conversions of their predecessors. The Super Seventies using the thrust reverser before landing is not allowed. 

The DC-8-71 resulted from the DC-8-61, but experienced major modifications, as well as the wing and the engine mounts had to be changed. Due to the higher weight of the new engines, the load decreased slightly, but the maximum takeoff weight remained unchanged. The first flight of such a converted machine took place on 15 August 1981st The authorization was granted 1982nd Overall, by the end of 1986 110 machines of DC 8-60er series have been modified accordingly.

The DC-8-72 and DC-8-73 were converted to the new engines without any external changes in the DC-8-62 and DC-8-63. These were 98.50 kN thrust delivered CFM56-2C5-turbofan engines with high bypass ratio. Alternatively, could also be a Pratt and Whitney PW used JT8D 209th The fairing has been redesigned by Grumman. The conversion led the company Cammacorp in Los Angeles. In addition to the modified engines and auxiliary power unit (APU) for autonomous power supply and an environmental management system were available.

the noise has been reduced by 70 percent by restructuring and a lower fuel consumption by 20 per cent of the engines reached, so that the range of the machine considerably enlarged.

Technical specifications :

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