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Tracing its lineage to the DC-9, the MD-80, and the MD-90, the Boeing 717, which had inceptionally been designated the MD-95, had been the last purely-McDonnell-Douglas aircraft and the first and only to have been transferred to Boeing for continued production.
Conceived as an advanced, low-wing, 100-passenger airliner with two aft-mounted, high bypass ratio turbofans and a t-tail most closely based on the MD-90, its immediate predecessor, the design, intended for high-frequency, short- to medium-range routes, had nevertheless inherently incorporated the 40-year development history of its earlier-generation family. Having carried the three manufacturer names of Douglas, McDonnell-Douglas, and Boeing, the basic airframe had featured three wingspans; three powerplant coresof the Pratt and Whitney JT8D, the International Aero Engine V2500, and the BMW Rolls Royce BR715; a vast range of thrust capabilities, from 12,000 to 25,000 pounds; four basic designationsof DC-9, MD-80, MD-90, and MD-95/717; passenger capacities varying between 90 and 180 in single-class arrangements; and eight fuselage lengths, as the DC-9-10, the DC-9-30, the DC-9-40, the DC-9-50, the MD-80, the MD-87, the MD-90, and the 717.
Intended as a next-generation DC-9-30 replacement, numerically the most popular DC-9 version with 662 having been sold, the originally-designated MD-95 features a 124-foot overall length, which is 1.7 feet shorter than that of the DC-9-40, permitting a 106-passenger complement in a four-abreast, two-two, first class cabin at a 36-inch seat pitch and a five-abreast, two-three, economy cabin at a 32-inch seat pitch. One hundred seventeen can alternatively be accommodated in a single-class, five-abreast configuration. Two underfloor holds facilitate baggage, cargo, and mail storage.
The state-of-the-art, two-person cockpit is equipped with six interchangeable liquid crystal display (LCD) units, an electronic instrument system (EIS), a dual flight management system (FMS), a control fault display system (CFDS), and an advanced Honeywell VIA 2000 computer, and is capable of category IIIA landings, with provision for lower-minimum IIIB operations.
Its all-metal, two-spar wing, like that of previous DC-9s, MD-80s, and MD-90s, features full-span, dual-position, five-section leading edge slats; two-section spoilers; three-section, double-slotted, trailing edge flaps; and manually-actuated, cable-connected ailerons differentially operated in flight for banking and roll control. The wings, with a 93.4-foot span, are sweptback 24 degrees for a maximum Mach 0.82 speed.
The t-tail, positioned well above the engines, eliminates engine thrust interference with its horizontal surfaces, whose elevators are cable-connected and manually operated, while the vertical stabilizers rudder is hydraulically-deflected with fly-by-wire trimming. The MD-95/717s tail surfaces employ thicker skins than those of either the preceding MD-80 or MD-90.
Powered by two aft-mounted, BMW Rolls Royce BR715-A1-30 high bypass ratio turbofans, each rated at 18,500 pounds of thrust, the aircraft, completely free of engine installation on its wings, generates maximum wing lift for optimum performance. Based upon the single-core BR700, the BR715 features a two-stage, high-pressure turbine; a 58-inch fan chamber; single crystal turbine fan blades; the largest combined blade and disk (blisk) ever employed by a commercial powerplant; and is thrust-reverser equipped. The 19-foot-long, 6,155-pound engine, the third basic type to have powered the DC-9 family, had first run on April 28, 1997, almost attaining 26,000 pounds of thrust at this time. It is the MD-95s sole powerplant.
The aircraft sits on a dual-wheeled, hydraulically actuated tricycle undercarriage.
Launch order for the initially-designated MD-95-30, comprised of 50 firm orders and 50 options, had been placed on October 19, 1995 by ValuJet, a DC-9 and MD-80 operator, and the prototype, a former Eastern Airlines DC-9-30 modified to MD-95 standard and registered N717XA, had been rolled out three years later, on June 10, 1998, first taking to the skies on September 2. The aircraft, reflecting Boeings prior-year acquisition of McDonnell-Douglas and its 7-dash-7 number scheme, had been redesignated 717, nomenclature shared by Boeings own KC-135A Stratotanker, the military derivative of the 707.
The first production aircraft, registered N717XD, had first rolled out on January 23, 1999, and the type had received its joint FAA and JAA certification nine months later, on September 1, after a 2,000-hour flight test program entailing 1,900 individual sorties and five airframes.
The first aircraft, N942AT, had been delivered to newly branded AirTran Airways, hitherto a 737 operator, which ValuJet had intermittently acquired, on September 23, and had been inaugurated into service the following month on the Atlanta-Washington route.
The 717-200, the initial and only version, had been offered with both basic and high gross weight options. The former, at 110,000 pounds, features a 1,430-nautical mile range with a 24,609 US gallon fuel capacity, while the latter, at 121,000 pounds, features a 2,060-nautical mile range with a 29,500 US gallon fuel capacity, but reduces the underfloor space because of the additional tankage and requires the upgraded, 21,0000 thrust-pound BR715-C1-30 engine.