Dassault Mercure

Dassault Mercure
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Type	140-seat jet airliner
Manufacturer	Dassault Aviation
Designed by	Marcel Dassault
Maiden flight	1971-05-29
Retired	1995-04-29
Primary user	Air Inter
Produced	1971-1975
Number built	12

Dassault Mercure was a twin-engined jet-powered French airliner. It was proposed in 1967, first production flight was in 1973 and last flew in 1995.

History

In 1967, backed by the French government, Dassault decided to propose a competitor to the Boeing 737. This would attack this market segment by the upper end, with a 140-seat jetliner, compared to the 100-seat -100 and the 115-seat -200 Boeing 737 variants then in production. This aircraft would be an opportunity for Dassault to show the civilian market its knowledge of high-speed aerodynamics and low speed lift capability previously developed by producing a long line of jet fighters, such as the Dassault Ouragan, Dassault Mystère and Dassault Mirage aircraft.

Marcel Dassault, founder and owner of Dassault, decided to give the airplane the name Mercure (French for Mercury). "As I wanted to give this airplane the name of a mythology god, I could only find one that had wings on his helmet and his feet, therefore the name Mercure," Marcel Dassault said. Extremely modern computer tools for the time were used to develop the wing of the Mercure 100. Even though it was larger than the Boeing 737, the Mercure 100 was the faster of the two. In June 1969, a full scale mock-up was presented during the Paris Airshow at Le Bourget airport. On April 4, 1971, the prototype Mercure 01 rolled out of Dassault's Bordeaux-Merignac plant. It was powered by two Pratt & Whitney JT8D-11 (6800kg of thrust). The first flight took place in Merignac on May 28, 1971. The second prototype, which was powered by two Pratt & Whitney JT8D-15 (the engine which would be used on all subsequent Mercure built), flew for the first time on September 7, 1972. On July 19, 1973, the first production airplane made its maiden flight. On September 30th, 1974, the Mercure 100 was certified for Category IIIA approach all-weather automatic landing (minimum visibility = 500ft, minimum ceiling = 50ft). This plane, built with Dassault's spirit, was nicknamed "Air Inter's fighter" by Air Inter's pilots. The Mercure 100 was also the first commercial airplane to be operated by a 100% female crew on one of its flight.

Dassault tried to attract major airlines to its product, and several regional airlines, by touting the Mercure 100 as the replacement for the Douglas DC-9. A few airlines showed some initial interest, but none placed an order, other than Air Inter, a domestic French airline. This lack of interest was due to several factors, including the devaluation of the dollar and the oil crisis of the 70's, but mainly because of the Mercure's operating range—suitable for domestic European operations but unable to sustain longer routes. At maximum payload, the aircraft's range was only 400 miles. Consequently, the Mercure 100 achieved no foreign sales. With a total of only 10 sales with the one of the prototypes refurbished and sold as the 11th Mercure to Air Inter, the airliner represents the worst failure of a commercial airliner in terms of aircraft sold. The number of sales is less than other poor selling aircraft such as the Concorde (14 produced, 20 including prototypes and preproduction aircraft), the VFW-Fokker 614, Convair 880 and 990, Vickers VC-10, etc.

It has been suggested that Dassault did not research the commercial aircraft market with sufficient depth, and that this is the reason for the Mercure's range shortfall. In actual fact, if anything Dassault researched things too well, and didn't spend enough time talking with potential customers. The primary reason for the range shortfall came in an examination of how aircraft such as the BAC 1-11, Boeing 737 and Douglas (later McDonnell Douglas) DC-9 were used, including an exhaustive study of the segments (flights) they were used on. Perhaps the military background Dassault had caused them to overlook the point, but while an airline might fly a 737 between, say Los Angeles and San Francisco (about 500 miles/800km), unlike a military aircraft, the commercial aircraft was not refuelled after every flight. Researchers who worked on the primary studies and discussed route planning for the Mercure at Dassault in the late 1960s and early 1970s have mentioned that this was an aspect of airline operations they never considered. And it proved to be the Achilles heel of an otherwise very good aircraft.

After the commercial failure of the Mercure 100, Marcel Dassault asked his engineers to develop a new version of the Mercure, the Mercure 200C. This airplane, studied in cooperation with Air France, was to carry 140 passengers with a range of 2200km. Several major airlines in the United States showed some interest in the project. However, the project design costs were also high. This might have been mitigated if the original Mercure had a larger fuel capacity or sufficient design strength so that additional fuel tanks could have been easily added.

At the beginning of 1973, a financial agreement was created with the French government to finance this program. Dassault was to receive a loan of 200-million French Francs from the French government, which would be paid back based on sales after the 201st airplane delivered. But Air France wanted an airplane powered with the Pratt & Whitney JT8D-117, which were quieter but larger than the JT8D-15. Dassault needed an additional loan of 80-million French Francs from the government to accommodate Air France's request. The French government replied to Dassault that it had to carry half of the development costs of the Mercure 200C on its own, which was impossible after the commercial failure of the Mercure 100. The Mercure 200C project was then cancelled.

Later, in order to answer a request from the DGAC (French FAA), Dassault proposed a Mercure equipped with a new engine developed by General Electric/Snecma called the CFM-56; this version came to be known as the Mercure 200. In 1975, contacts were made with Douglas and Lockheed to build and sell the Mercure 200 in the US, and with SNIAS to build it in France. But Marcel Dassault was concerned about the fact that the CFM-56 had not had a single order yet, and might cease to be produced before the Mercure 200 could be built. Meanwhile, Douglas introduced a stretched version of the DC-9, which was in direct competition for orders with the Mercure 200. Contacts with Douglas logically ended at that point. Dassault then initiated contacts with General Dynamics, its primary competitor on the military jet market where the Mirage F1 was facing the F-16. But nothing would come out of these contacts.

In 1981, Marcel Dassault tried to revive the Mercure program once more by selling production licenses in the US, with no success.

Some aeronautical rumors say that the Mercure 200 project and its drawing package was eventually sold or given by Dassault to Aérospatiale, which used it as a base for the design and development of the Airbus A320. The cockpit design is completely different. Even the fuselage width and aircraft dimensions are different. The design philosophy that the aircraft's range should not be so limited to preclude sales was apparently learned as the Airbus A320, which has been a resounding sales success, is not hampered in this regard.

Production

Hoping for mass production of the Mercure (the 300th airplane was planned to be delivered by the end of 1979), Dassault created four plants especially for the Mercure program: Martignas (close to Bordeaux), Poitiers, Seclin (close to Lille) and Istres. On January 30th, 1972, Air Inter ordered 10 Mercures, which had to be delivered between October 30th, 1973 and December 13th, 1975. Due to the lack of other orders, the production line was shut down on December 15th, 1975. Only a total of 2 prototypes and 10 production airplanes were built. One of the prototype (number 02) was eventually refurbished and purchased by Air Inter to add it to its fleet.

Career

On April 29, 1995, the last two Mercures in service flew their last commercial flight. All Mercures are now retired with an impressive history: 360,000 flight hours, 44 million passengers carried in 440,000 flights, no accidents, and a 98% in-service reliability.

Operators

• Air Inter.

Specifications (Mercure 100)

General characteristics

• Crew: 3: pilot, co-pilot and flight engineer
• Capacity: 150 passengers
• Length: 34.84 m (114 ft 3 in)
• Wingspan: 30.55 m (100 ft 3 in)
• Height: 11.35 m (37 ft 4 in)
• Wing area: 116 m² (1,248 ft²)
• Empty weight: 31,800 kg (69,960 lb)
• Max takeoff weight: 56,500 kg (124,300 lb)
• Powerplant: 2× Pratt & Whitney JT8D-15 turbofans, 68.9 kN (15,500 lbf) each

Performance

• Maximum speed: 925 km/h (499 knots, 578 mph)
• Cruise speed: 870 km/h (470 knots, 540 mph)
• Range: 1,700 km (920 nm, 1,100 mi)
• Service ceiling: 12,000 m (39,000 ft)
• Rate of climb: 16.7 m/s (3,300 ft/min)
• Takeoff roll: 2,750 m (9,000 ft)
• Landing roll: 1,650 m (5,400 ft)

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• Airbus A320
• Boeing 737

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• List of airliners