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1993 avionics conference and exhibition: integrated avionics — how far, how fast? — conference proceedings, London, 1–2 December 1993 ERA Report 93–0890, Leatherhead, January 1994. Non‐members £90.00, members £80.00. Not available with a membership voucher

A new prototyping technology named QuickCast, developed by USA‐based 3D Systems, has been introduced to the European market. Since its USA introduction 12 months ago, the method has been adopted by investment‐casting foundries and end‐user industries such as aerospace.

Invented and manufactured by the French company AHG (Ateliers de la Haute‐Garonne), the MATT rivet has been specially formulated to prolong the life of riveting in thin sheet metals. The original design allows controlled expansion of the head and shank, and most importantly, the head expands into the countersink to ensure a precise interference fit which does not require additional sealants.

Civil aviation authorities from some 40 countries will meet in Singapore (at the Mandarin Singapore Hotel) from 11 to 29 January 1983 under the auspices of ICAO to plan the future development of the aviation infrastructure in Asia and the Pacific — a region which has seen the fastest growth of traffic in the world.

The aircraft manufacturing industry places a high priority on safety and spends many billions of pounds in developing and testing new military and civil aircraft to the highest safety standards.

GE Aircraft Engines and Southern Aero Corporation of Ozark, Alabama, have agreed to develop a T700‐powered UH‐1 Huey demonstrator and to fly the high‐performance aircraft early next year.

Aircraft manufacturers for a long time have been looking to reduce the weight of on board equipment to enhance performance both from commercial aspect and from military aspect. The existing wired technology, using cables to connect different on board line replaceable unit apart from increasing the weight also increases the complexity related to electromagnetic interference, installation and maintenance. With continuous technology upgradation in the wireless domain, aviation industry is in the process of using wireless technology for intra-aircraft communication. Wireless technology can meet most of the challenges of modern avionics systems and significantly reduce the weight. This paper aims to look at various aspects of implementing a wireless network including issues related to wired network, aircraft channel, interference issues, suitable wireless protocols for aircraft applications and security aspects.

The paper has relied on literature study on wireless avionics intra-communications (WAIC) and the research work carried out in specific areas related to channel inside an aircraft, interference issues of wireless systems with onboard and external systems operating in the same band and security issues related to wireless network and security requirements of implementing an avionics wireless network (AWN). To identify suitable wireless protocol for AWN literature review and simulation to compare different protocols was carried out.

A single wireless protocol may not be suitable for all aircraft systems, and therefore, there may be a requirement to use multiple technologies. Mutual interference is not expected between WAIC systems with on board and external systems operating in the same band. The channel inside an aircraft is expected to be Rician (LOS) or Rayleigh (NLOS). However, additional measurements may have to be undertaken to have a generalized channel model. Security aspects in an AWN are critical and needs to be analyzed in detail prior to any wireless deployment.

Implementation of wireless technology can pave the way for usage of wireless technology for future generation avionics. With International Telecommunication Union allotting dedicated band for WAIC operations, considerable amount of research has been initiated in this field. It is believed that in the coming 2-3 years, the designers will be ready to replace the existing data wires with wireless transceivers. With radio technical commission for aeronautics and EURACAE involved in development of minimum operations performance standards for WAIC systems use of wireless for intra communication is bound to happen. Therefore, it is necessary to look at different issues for integrating wireless in the avionics domain.

The existing studies have been carried out in individual domains of using wireless in avionics. Separate studies and research work has been carried out for identifying wireless protocols, aircraft channel models, interference issues and security aspects. The paper has attempted to look at all these aspects together including certification.

LAUNCHED at the Farnborough International Airshow last year by FT Technologies Ltd. the FT280 Synchro/Resolver Test Set incorporates in one versatile instrument an Angle Position Indicators, Simulator and Reference Oscillator and is designed for testing and evaluating a wide range of synchro and resolver‐based avionics equipment.

Major technical advances were featured at the Show, particularly those developments that will be coming into service in the very near future. An outstanding demonstration was given by the Airbus Industrie A 300B2 Fly‐By‐Wire (FBW) whose autopilot simulates the control laws of the A 320. The pilot flies the aircraft through the FBW autopilot using the sidestick controllers as in the A 320, which is due to make its first flight in March, 1987. A convincing display by the A 300 FBW began with a slow fly‐past in landing configuration with gear and flaps down at a speed of about 100 knots. At mid‐runway position, the crew simulate a windshear encounter and the captain pulls back on the stick as might happen in such a situation. In a standard ‘conventional’ aircraft, this would lead to a stall with potentially disastrous consequences, but with FBW the pitch angle increases to the point where the wing reaches its maximum lift position and stays there. The ‘alpha‐floor’ protection incorporated in the aircraft then automatically increased engine power and the combination of maximum lift and power results in a climb‐out at 3,000ft/min. In another manoeuvre, the aircraft is positioned at an angle of attack of 15.5° in order to stabilise speed at 95–100 knots and only just below the limit of 17° — 18°. Also demonstrated was a stall turn with the nose up to maximum angle of attack and bank angle of 30° which stops there despite the fully‐deflected stick position. The engine power in this manoeuvre is controlled manually.