Guy Norris/LOS ANGELES
HONEYWELL HAS released details of its new digital-gyro ADIRS (air-data/inertial-reference system) which forms the core of the inertial packages selected for the Boeing 737-600/-700/-800 family.
"The digital gyro is also base-lined in our VIA [versatile integrated avionics] 2000 package and is the central product for the way in which we're thinking about the future," says Honeywell Air Transport systems marketing vice-president, Tom Goodman.
At the heart of the new system is the GG1320 laser gyro developed for the Boeing 777. "We've built up digital gyro technology around it, giving significant weight reductions and the need for much lower power," says commercial avionics-system sensor-products vice-president, Ralph Pamperin.
"Before, we had lasers powered by an external high-voltage power supply up to 2,000V, and a gyro output which was transmitted in a series of pulses and filtered and converted by outside electronics through an interface with 26 wires," says Pamperin. "With a digital gyro, we need only 15V standard power, and it provides direct digital output. It's a greatly simplified device and weighs less [around 8.2kg, compared to 12.7kg for earlier gyros]."
The standard 737 ADIRS fit will be a three-axis configuration packaged in dual 4 MCU-sized containers. This is roughly half the size of earlier Honeywell GG1342 gyro-based inertial systems in the 757, 767 and 747-400, which are contained in ten MCU-sized packages. The first systems required 14 processing cards and two power supplies, while the latest ADIRS for the 737 will require just three cards and a single power supply. "VIA 2000 standard offerings would be a dual or triple 4 MCU package," adds Goodman.
Military versions of the digital gyro (with integrated power supply and embedded global-positioning system), are being supplied to the US Air Force. The first commercial GG1320 sensors are being tested.
As part of its work with Boeing on the new 737, Honeywell has also helped the manufacturer make provision for the potential use of ADIRS on existing models. The company is also in talks with 100-seat regional-jet groups about the use of the VIA 2000 and is believed to be in negotiations with Airbus Industrie and McDonnell Douglas about applications on new and existing platforms.
The VIA 2000 system is a modular avionics concept based around the architecture developed for the Boeing 777's airplane information-management system.
The new avionics concept was first revealed by Flight International (31 May-6 June) as being part of a potential flight deck upgrade for McDonnell Douglas DC-10s.
Source: Flight International
