CONFUSION OVER the cost, time scale and benefits of the aeronautical telecommunications network (ATN) which will be at the heart of the full-up FANS system is causing concern as the system may be usurped in the near term by the less capable systems based on the 622 standard.
The 622 system, which is character-based, enables air-traffic-control data to be sent over the aircraft's ACARS datalink, but its format is such that messages cannot be prioritised, and take longer to send than with ATN, making the system unsuitable for high-density areas such as the USA and Europe.
The 622 datalink is already operating in the South Pacific, with carriers flying the FANS 1 package aboard a Boeing 747-400. Further routes in Asia and the Far East should follow.
The time scale for ATN systems is less certain, with the earliest projections suggesting that it could become available in the North Atlantic and USA after 1998.
Concerns have been raised especially among Europe's air-traffic-service providers, that if 622 becomes a de facto standard, it could slow the progression towards ATN.
Dave Allen, who manages FANS projects at Boeing, replies that, as yet, there is no "clear business case" for ATN.
At the Flight International conference he challenged air-service providers, offering to make available Boeing's economic-modeling capability to them to see if they could make cost equation work.
Source: Flight International
