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Home | Update | LATEST ISSUE | Gallery | FR Profile | Datafiles | FR 4/98 FAIRCHILD DORNIER 328JET THRUSTS INTO NEW CLASS by Christopher Hess Turboprops are out. By now passengers expect the comfort of the big jetliners on short haul flights. As far as it makes economical sense, the regional airlines are looking for jet powered alternatives to their turboprop fleets. At the moment this especially applies to the class of 30seater turboprops, which shows a dramatic decrease of sales over the past three years. Even if this favourable position could not have been foreseen two years ago, it is not by chance that Fairchild Dornier is waiting in the wings today with a 30seater regional jet. After the American manufacturer Fairchild Aircraft took over 80 per cent of Dornier Aviation, belonging to Dasa at that time, the new Fairchild Dornier underwent a rigorous redesign and cost cutting exercise. Since production of the turboprop 328 was still not profitable, (so far 99 firm orders and 41 options), the new management decided to look again at already existing plans for a jet-powered 328. These plans had been rejected by the old management and had subsequently been shelved. Under the strict management of Earl J Robinson, Fairchild Dornier senior vice president product development, the company was successful in getting the 328JET airborne within a year after the program was launched. When the jet's premiere was celebrated on 4 February, it had already accomplished its first flight successfully and on time on 20 January. The two 328 versions' most noticeable difference are the engines. Instead of the turboprop engines, which are integrated into the wings of the original 328, the 328JET is powered by two Pratt & Whitney Canada PW306B turbofans, each generating 26.9kN (6050 lbs), which are installed on engine pylons. In order for the thrust to be converted into a higher cruise speed, the 328 had to undergo some additional aerodynamical changes. The turboprop 328 had been designed for speeds of up to 365 kts (676 km/h). When work on the 328JET started an increase to 375kts (695km/h) was planned. By extending the trailing edges of the wings by approximately 10 centimeters, the aerodynamic drag of the wings could be reduced so much that the jet is now supposed to reach speeds up to 400 kts (741 km/h). Since the turbofans need around 30 per cent more fuel than the turboprops, the capacity of the wing tanks was increased by 222 liters to 4490 liters. The 32-seater (Europe) and the 34-seater (USA) now have a range of up to 900 nm (1668 km). A further enlargement of the fuel tanks will be necessary to give the jet the 2400 nm (4445 km) of the 328JET's 10-seater business version which Fairchild Dornier is simultanously launching to the regional aircraft variant. Because of the jet engines there will be no propeller levers in the cockpit. A further change to the flight deck concerns the engine indication and crew alerting system (EICAS) which now displays information of the digital engine control (FADEC) of the two turbofans. Also, the jet has two fully AC powered hydraulic pumps. To compensate for the lower drag of the jet during landing, still being able to operate from short runways, the brakes were re-inforced and a second anti-skid system was added. In order to allow the best possible ground contact for the wheels during landing, the jet is equipped with ground spoilers. Like in the turboprop version, the cell of the 328JET is designed for 60000 cycles. The fuselage had to be re-enforced slightly since, with a cruising altitude of 31000 ft, the jet will be flying up to 6000 ft higher than the original 328 with the cabin pressure staying at the same altitude (8000 ft). The two main spars (24 and 26) were strengthened. After three test flights and six hours and 25 minutes flight time at the day of the premiere celebration in Oberpfaffenhofen, "the jet's performance looks promising", Fairchild Dornier's chief testpilot Meinhardt Feuersenger explains. Based on the jet's performance in the first flights, Feuersenger claims, that "the calculated performance data will be achieved and even surpassed in some of the specifications." In an altitude of 17000ft, the climb rate has been increased from 2600 to 3400ft/min at a speed of 150 kts (278km/h). At an airspeed of 200 kts (370km/h) this rate has even doubled from 2000 to 4000 ft/min. According to Fairchild Dornier, the 328JET will need just over 14 minutes to reach an altitude of 31000ft. Feuersenger is enthusiastic about the jet's flying qualities: "It's a pilot's plane." The passengers do not miss out, either. The original 328's propeller wash used to have an adverse effect on the airframe, which was especially noticeable during power adjustments. This effect has completely vanished. The noise level in the cabin has also decreased considerably. As the first test flights brought to light, there is also a negative side to the jet's aerodynamic benefits. The smooth surfaced jet with the lower drag engines does not decelerate very good in flight, resulting in low sink rates. An additional air brake system is needed to remedy this. The ground spoiler could possibly be used as speed brake. So far, test aircraft number two was used for the test flights. The aircraft was already utilized for the test program of the original turboprop 328 and has now been modified with the jet engines. A second prototype, the first production 328JET, will join the test program on 30 April. By the end of June a third prototype is going to follow and then in August the fourth one. The certification of the European aviation authorities (JAA) is planned for February 1999 and the FAA certification will reportedly follow one month later. Around that time the development of new products will probably be at full swing at Fairchild Dornier, since a decision about the launch of the 428JET is expected within the next weeks. With a fuselage, that is lengthened by approximately three meters, a one-meter wing tip extension, larger flaps and more uprated engines (6600lbs), this jet will offer room for 42 to 44 passengers. Furthermore, Fairchild Dornier is seriously considering the development of a 70-seat 728JET. This aircraft will no longer be based on the 328, but will be the start for an all-new product line. If the program is launched in the spring of this year, the aircraft will be on the market in 2001. The development will take approximately 39 months and the costs will be around $500 million. The 70-seater might also be offered in a shortened version with 55 seats (528JET) and a stretched version with room for 90 passengers (928JET). The immediate goal for the American-German enterprise, however, is the marketing of the 328JET. Up to now there are 20 firm orders and 15 options for the jet (both regional aircraft and business jet). According to Fairchild Dornier, the break-even is reached at 100 aircraft sold. Reportedly, there are talks with different American carriers underway, concerning sales of a total of several hundred jets. From page 30 of FLUG REVUE 4/98 Home | Update | LATEST ISSUE | Gallery | FR Profile | Datafiles | FR 4/98 Copyright 1998 by Motor-Presse Stuttgart. All rights reserved. Last updated March6, 1998 FLUG REVUE, Ubierstr. 83, 53173 Bonn, Germany