Development history from the Douglas DC-9 to the Boeing 717

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The development history from the Douglas DC-9 to the Boeing 717 began in 1965 and includes the DC-9 and its successors, which were produced until 2006. They were originally the first commercial aircraft with jet propulsion today's " volume class " of aviation in the field of aircraft for 100 to 180 passengers. The first flight of these short-haul aircraft took place on February 25, 1965 in the version DC-9 Series 10 . The basic model of the low - wing family of US aircraft manufacturers Douglas , McDonnell Douglas and Boeing is the Douglas DC-9 , of which the successor models of the McDonnell Douglas MD-80 (DC-9-80) , the McDonnell Douglas MD-90 and eventually the Boeing 717 were derived. These are each technically improved models with different passenger capacities. However, the principle of rows of five passengers and the rear engines is common to all versions.

Although not sold under the manufacturer name McDonnell Douglas, the Boeing 717 also belongs to the same family, as it was originally developed as the MD-95 based on the MD-90. Before development was fully completed, however, Boeing took over McDonnell Douglas in 1997 and eventually sold the MD-95 under the name Boeing 717.

Boeing 717 of the AeBal

history

The archetype

Douglas DC-9 from UM Air

In July 1963 Douglas began developing a small sister model to the successful Douglas DC-8 , also with jet propulsion. Even then, the design envisaged an aircraft with - similar to the Sud Aviation Caravelle - an engine configuration at the rear combined with a T-shaped elevator and vertical stabilizer . In the original version, seats for 90 passengers could be arranged in rows of five. The first flight took place in February 1965. After a comparatively short time, the aircraft was also certified by the Federal Aviation Administration (FAA) and was therefore put into service in December 1965.

In the years that followed, numerous modifications of the first DC-9 version were developed and produced. There were a total of five different "series", with each series partially comprised several sub-versions. These sub-versions mostly differ only slightly, for example in the maximum take-off weight ( MTOW ). All DC-9s were powered by variants of the Pratt & Whitney JT8D .

The further development

McDonnell Douglas MD-83 of the Swiss

After the success of the DC-9, Boeing developed the Boeing 737, a competing aircraft . This, as well as the growing success of the stretched variants of the DC-9, prompted Douglas to plan an even longer variant, which was temporarily given the name DC-9-55, later it was then in DC-9-RSS ( R efan, S uper S referred tretch) as well as DC-9-80. Even before the first units were put into service, the name MD-80 was chosen for marketing purposes , and the name Super 80 was also circulating at this early stage . This should make the leap in development even clearer and also reflect the new identity of the McDonnell Douglas company (which since 1967 was no longer just called "Douglas Aircraft Company"). Last but not least, the negative image after the series of accidents of the DC-10 contributed to the renaming. On June 26, 1979, the second prototype took off for its maiden flight, while the first was still being used for static tests. The test program went well, but on June 19, 1980, one of the two test machines shot over the runway in Yuma, Arizona . When a crane fell over during recovery , both test aircraft were damaged. The mentioned second prototype had to be written off afterwards and the program was set back by a few months. Nevertheless, the first aircraft, now called MD-81 by the manufacturer, were delivered to the first customers Swissair and Austrian Airlines at the end of 1980 .

However, the official type designations in the respective type approval remained, i.e. DC-9-81, -82, -83 and -87. Only the MD-88 and the later MD-90 were officially approved under these designations.

In the early 1980s, new orders came in rather slowly. Only the sales deals with Alitalia, American Airlines, Finnair and TWA secured the production and there was a sometimes very high demand. The order from American Airlines for 67 MD-82s and 100 options was the largest order in western aviation at the time.

In the mid-1980s, Boeing also brought out a further development of its Boeing 737. In contrast to the MD-80, the Boeing 737-300 was equipped with modern turbofan engines of the type CFM56 and due to the wider fuselage, the capacity could be increased more easily, as a fuselage extension was possible without major structural changes. It therefore began to regain the market share that McDonnell Douglas had captured from the Boeing 727. With KLM and JAT , two important former DC-9 customers ordered the competing product from Seattle . Overall, McDonnell Douglas expanded the MD-80 over time to a family with five members, who mainly differed in range and maximum take-off weight (MTOW). Only the MD-87 was a major modification compared to the other MD-80 types due to its much shorter fuselage.

McDonnell Douglas tried to get more business again with the MD-87. Due to the shorter fuselage already mentioned, this aircraft had a similar capacity to the Boeing 737-300 and thus expanded the capacity range of the MD-80 downwards. The main customers were Aeroméxico , Iberia and the Japanese JAS . Under pressure from Delta Air Lines , McDonnell Douglas also redesigned the MD-82, bringing out the MD-88 in 1988. Other customers of this variant were Aviaco , Reno Air , Onur Air and Air Aruba .

From 1987, the modified tail cone introduced with the MD-87 became standard for all MD-80 versions ex works, regardless of the sub-version. Before that, they had a tail cone similar to that of the original DC-9 models. However, many airlines retrofitted their older MD-80s with this new, "toothpaste tube tail" called tail section. The MD-87, on the other hand, can be distinguished from the other versions not only because of its length, but also by the more angular and slightly higher vertical stabilizer. In contrast, the MD-81, -82, -83 and -88 show no external differences.

The crew of the long MD-80 consists of six people (two cockpits / four cabins), and the shorter MD-87 of five.

The end

However, in the late 1980s, Airbus began to take on the role of McDonnell Douglas as an alternative to Boeing with the A320 Family . Like the 737 of the second and third generation, the A320 family was equipped with the more modern engine and, as a new development, was state-of-the-art and was able to overtake it with future-oriented technologies such as modern avionics, fuselage parts made of fiber composite materials or a fly-by-wire system . Thus the MD-80 was clearly at a disadvantage in terms of performance and consumption.

Nevertheless, McDonnell Douglas continued to be very successful and was able to deliver 139 MD-80s each in 1990 and 1991, the highest production rate in production history. With relatively few exceptions, McDonnell Douglas was able to win many regular European customers for the MD-80. After the takeover of McDonnell Douglas by Boeing in 1997, the end of MD-80 production was quickly sealed. Although the series was briefly renamed Boeing MD-80 , the last machine, an MD-83 for TWA , was delivered at the end of 1999.

McDonnell Douglas MD-90

In order to survive against the European competitor A320, McDonnell Douglas started another evolutionary revision of the DC-9 under the name MD-90 in November 1988. A whole family of models was planned again, but only the first flight of the standard version MD-90-30 took place, which was then manufactured in comparatively small numbers until 1999. The main reasons for the failure are to be found in the fuselage and in the technical equipment: In contrast to earlier types, the latest technology turbofans have a high bypass ratio, which leads to significantly lower kerosene consumption and much less noise, the weight of the engine however, increases as a result. Because of the tail arrangement of the engines, the fuselage had to be lengthened and counterweights had to be attached in the bow in order to find a regulated center of gravity - the capacity of the aircraft, however, could not benefit from this fuselage extension, which in turn resulted in lower operating costs than with the MD due to the high weight -80 but was unable to catch up with the A320 Family in terms of operating costs. Furthermore, the long but narrow fuselage was found to be uncomfortable by the passengers and the cockpit layout was not state-of-the-art.

Another McDonnell Douglas project that should make it a success again was the McDonnell Douglas MD-95. This was pursued from 1995 and continued as the only project after the takeover of McDonnell Douglas by Boeing in 1997 as the Boeing 717, so that flight tests could begin on September 2, 1998. Certification took place for the first time in 1999 jointly by the Federal Aviation Administration (FAA) and the European Joint Aviation Authorities (JAA). Although this aircraft was the most economical aircraft and next to the A318 the most modern in its class, Boeing stopped production in 2006 due to a lack of demand. The last two aircraft produced (No. 154 and 155) were delivered to Midwest Airlines and AirTran Airways on May 23, 2006 . This ended the era of what is currently the third most successful civil aircraft program in terms of numbers.

use

General

Douglas DC-9 of the Itavia

The McDonnell Douglas short-haul family remains one of the most successful jet airliners of all time. Between December 1965 and the end of production in May 2006, a total of 2438 copies of the aircraft family founded by the DC-9 were delivered. Of these, 976 were on the DC-9, 1191 on the MD-80, 116 on the MD-90, and 155 on the 717. This also includes 41 copies of the DC-9 specially built for the US military.

McDonnell Douglas short haul aircraft today

In August 2006, around half of the DC-9s were still in operation, now mostly with smaller companies. The last major company still using DC-9 was Northwest Airlines . Northwest was also the largest DC-9 operator, with 68 DC-9-30s and a further 8 DC-9-40s and 29 DC-9-50s (as of December 2006). Due to the huge increase in the operating costs of the DC-9 due to the increased fuel prices, Northwest declined the type more and more. The inventory was reduced from 103 (2006) to 68 (2008) and then after the takeover by Delta to 19 copies (2012). The last Delta flight with a DC-9 was on January 6, 2014. Today the DC-9 can still be found mainly in African and South American countries.

In the meantime, the first airlines have started to retire their MD-80 fleets. Nevertheless, the MD-80 is still widely used, especially in the USA. Delta Air Lines, for example, flew 118 copies in 2012, American Airlines even flew more than 330 after taking over the TWA, some of which, however, are mothballed and not in operation. Smaller airlines such as the now insolvent Jetsgo from Canada or Lion Airlines from Indonesia have discovered the MD-80 for themselves. Some of the oldest machines from Northwest Airlines and US Airways stocks have now been scrapped. Nevertheless, the MD-80 is still considered a very reliable and durable airliner, which is known for its robustness and good workmanship. In the long term, however, it can be assumed that the MD-80 will disappear from air traffic with the ever more stringent noise regulations and will be replaced by more modern aircraft from the Airbus A320 family or the 737NG . A retrofittable silencer has been available for the MD-80 since mid-2006, which enables the MD-80 to meet the noise regulations of Chapter 4.

The McDonnell Douglas MD-90 and Boeing 717 continue to be used by various western airlines.

Sales figures

Detailed list of orders and deliveries
DC-9-10 DC-9-20 DC-9-30 DC-9-40 DC-9-50 MD-81 MD-82 MD-83 MD-87 MD-88 MD-90 B717-200
Orders 137 10 662 1 71 96 132 569 265 75 150 116 155
Extraditions 137 10 662 1 71 96 132 569 265 75 150 116 155
Customers 23 2 54 15th 11 11 34 30th 10 5 14th 9
(Status: end of December 2006)

1 : Including 41 military DC-9-C9A, -C9B and -VC-9C, some of which were also DC-9-40

Technical specifications

Parameter DC-9-10 DC-9-21 DC-9-30 DC-9-40 DC-9-50 MD-81 MD-82 / -88 MD-83 MD-87 MD-90-30 B717-200 B717-300X
Length [m] 31.80 m 36.60 38.30 40.70 45.10 39.70 46.50 37.81 42.15
Span [m] 27.30 28.40 32.80 32.87 28.45 34.09
Height [m] 8.38 9.05 9.30 9.40 8.92
Wing area [m²] 86.80 93.00 92.97
Max. Takeoff weight [kg] 41,177 44,492 49,940 51,756 54,934 63.503 67,812 72,575 63,503
67,813 1
70,760 49,895
54,884 2
56,245
Cruising speed [km / h] approx. 900 circa 811
Cabin width [m] 3.11 ? like DC9?
Passengers (max.) 90 115 125 139 172 139 172 134 145
Range [km] 2,340 3,430 3,030 3,120 3,030 2,879 3,789 4,635 4,395 3,860 2,645 <2,645
drive Two Pratt & Whitney JT8D- 7 Two Pratt & Whitney JT8D- 200s Two IAE V2525-D5 Two BR715
Thrust per engine [kN] 62.3 66.7 68.9 71.2 82.0 89.0 93.4 89.0 111.0 82.3 <93.4
1 : Version with increased takeoff weight 2 : Value for HGW version (HGW stands for "High Gross Weight", increased gross weight)

literature

  • Modern Civil Aircraft 10: McDonnell Douglas DC-9 / MD-80 / MD-90 by Günter Endres, Ian Allan Ltd. 1991 ( ISBN 0-7110-1958-4 ) - English

See also

Individual evidence

  1. ^ FAA TCDS , accessed November 5, 2015
  2. EASA TCDS , accessed on November 5, 2015
  3. Boeing announcement about the end of production ( Memento of the original from October 12, 2010 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.boeing.com
  4. Bombardier Aerospace : CRJ-Series - A Story Of Success (PDF document)
  5. Pacific Business News: Northwest Airlines to ditch DC-9s (January 21, 2008)
  6. a b Delta: Aircraft Fleet (Feb. 12, 2013)
  7. http://www.aero.de/news-18805/Delta-mustert-ihre-letzt-DC-9-aus.html
  8. List of orders and deliveries of short-haul aircraft from McDonnell Douglas

Web links

General

Commons : Short-haul Aircraft by McDonnell Douglas  - Album with pictures, videos and audio files

Manufacturer pages (Boeing, English)