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The Fokker F.70 and F.100 Regional Jet

1. Design Evolution:

Complementing the F.27 Friendship turboprop, the F.28 Fellowship was intended to offer pure-jet comfort, higher speeds, and reduced block times traditionally associated with larger twins, such as the BAC-111, the DC-9, and the 737, to regional route operators. But, following the demand for increased capacity in all markets, and seeking to incorporate then-emerging technological advances, Fokker soon envisioned a successor that would not only infringe on the traditional, short-range jet segment, but replace many of its first generation types.

Initial design studies, designated P315, F.28-2, and Super F.28, were undertaken in 1977 and were based upon the F.28-4000-the highest capacity and numerically most popular of the six versions, but featured a stretched fuselage for up to 115 passengers, a new wing, 16,500 thrust-pound engines, a Mach 0.75 cruise speed, and a 1,500 nautical mile range. Intended program dates, characterized by two-year intervals, included 1979 for the type’s launch, 1981 for its first flight, and 1983 for its certification.

Although powerplant progress had been made since the initial de Havilland Ghost and Rolls Royce Avon engines had been introduced, with the likes of the Spey and Spey Junior that respectively powered vr 教育 the BAC-111 and the F.28, the number of types was still very limited, and this served as the greatest obstacle to a more modernized and ambitious Fellowship successor.

Projected powerplants included an improved version of the Rolls Royce Spey, another of the Pratt and Whitney JT10D, a scaled-down CFM-56, and a proposed Rolls Royce RB.432. However, their manufacturers were either reluctant to launch such engines or optimized them for aircraft with higher gross weights than Fokker was considering.

In the event, these obstacles may have become opportunities, because still-increasing demand dictated even greater capacities-of about 150 passengers-on short- to medium-range routes, and a fuselage wide enough for six-abreast, single-aisle coach seating-or one more than the BAC-111, DC-9, or F.28 had offered.

Yielding to market demand, and buoyed by new generation, 20,000 thrust-pound CFM56-3 and RB.432 turbofans, Fokker elected to deviate from its five-across seating standard and offer a sixth one with a new proposal designated F.29, which would enter the ranks of other second-generation 150-seaters. Capacity, double that of the F.28, was 138 at a 34-inch pitch or 156 at a 30-inch pitch, and range was foreseen as 1,700 nautical miles, although its overall configuration remained identical to its smaller predecessor with two aft-mounted engines and a t-tail to avoid exhaust interference with the horizontal stabilizers. The first flight was now slated for 1983.

Because the development costs of such an ambitious project were beyond the economic viability of a small Dutch regional aircraft manufacturer, however, program reality was contingent upon a link with a risk-sharing partner.

McDonnell-Douglas, seeking to offer its own higher-capacity, advanced DC-9 successor with its projected, 150-passenger Advanced Technology Medium Range ATMR-II proposal, accepted the Fokker offer and, combining it with the similarly configured F.29, devised the McDonnell-Douglas Fokker MDF-100, intended for 2,000 nautical mile sectors with 153 dual-class, six-abreast passengers.

Although the t-tail was retained, its two turbofans were relocated and were now pylon-mounted below and ahead of the high aspect ratio, supercritical wing.

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