Andrew Doyle/MUNICH
Fairchild Dornier has completed initial tests of the 728JET flight control system using an "iron bird" rig at its Oberpfaffenhofen factory near Munich as it pushes ahead with the aircraft's ambitious development schedule. The manufacturer is gearing up to begin final assembly of the prototype 70-seat regional airliner in August.
The full-scale test rig is configured to represent the 728JET's primary and secondary flight control systems and landing gear and thrust-reverser actuators, and Fairchild says the operation of the aircraft's aileron and multi-function wing spoiler actuators has already been demonstrated.
The rig system will be used in conjunction with an engineering cockpit simulator to assist the certification process, says Fairchild, allowing the 728JET to be "flown" one year before the prototype's first flight.
Installation of wiring harnesses for the rudder, elevator and spoilers has been completed and the rig is due to become fully operational this quarter after the hydraulic system is added.
The 728JET's digital fly-by-wire flight control system is being developed by a team of contractors including Honeywell, Hamilton Sundstrand and Parker Aerospace.
Meanwhile, fabrication of the first fuselage skin panels has begun at Operpfaffenhofen. The fuselage subassemblies will be joined by a numerically controlled gantry riveting robot which is undergoing acceptance trials and is due to be installed by April.
According to Fairchild, critical design reviews of "all major structural items and systems" were finished in December. The 728JET digital mock-up was expected to include "80% of the total aircraft by the end of the year [2000]", says the company.
First metal was cut in September by SABCA in Belgium, which is responsible for the cockpit structure and a section of the rear fuselage. The wings and empennage are being built by EADS Spain, which began making subassemblies in October.
Assembly of the first centre wing box is scheduled to start in January, followed by the outer wing box a month later. Final assembly of the first wing is expected to begin in May, ready for mating with the first fuselage in August.
Also under way are fatigue and damage tolerance tests of a 728JET fuselage barrel section, with 200,000 simulated flight cycles due for completion later this quarter to test the performance of the fuselage skin and passenger window structure.
An acoustics test specimen comprising a structural skin panel with windows is testing various combinations of acoustic treatments and interior trim panels to achieve the optimum balance between weight and noise reduction.
Lufthansa CityLine is due to take delivery of the first 728JET by July 2003, although Fairchild aims to achieve the first handover two months earlier if it maintains the latest production schedule.
Source: Flight International
