Draft ICAO Circular on NLA.pdf - Airports Council International

<strong>ICAO</strong> Version 4.1 — 15 March 2004
A-6
Technology evolution
Possible NLA design features that may impact aerodrome elements
There has been a steady progress over past decades in aviation technology, enhancing the accuracy and
reliability of aircraft operations. These technologies, along with improvements in airport infrastructure and
improved operational procedures of airports and aircraft have contributed to the overall aviation safety. A
review that was carried out by a members State showed that the rate went down from 3.5 fatal accidents per
million flights for the first generation of modern aeroplanes (e.g. B707) to 1.6 for the second generation
aeroplanes (e.g. DC-10, A300) and to 0.5 for the third generation aeroplanes (e.g. B777, A340). Listed below
are recent technology features already available on existing aircraft models as well as those that may become
available in the near future for a possible integration in the NLA, such as the A380. This is not an exhaustive
list nor is it intended to define the required technology improvements for the NLA. Technology features
below are grouped under the relevant airfield elements.
Runway and shoulder width:
— Nose wheel steering augmentation system: Provides reduced steering angle with
increasing ground speed: This may reduce the likelihood of nose wheel skidding.
— Two stage lift dumping: in the event of uneven gear touchdown at landing, the spoilers
provide partial lift dumping to ensure all gears achieve ground contact prior to full spoiler
deployment. This may ensure that antiskid operation do not result in asymmetric braking
problems.
— Back up nose wheel hydraulic power source
Taxiway turn fillet
— Taxi cameras (not mandatory for dispatch): cameras are valuable in the pilot training phase,
but are considered to be of little use in the field. Pilot self-learning of oversteer turning
technique on taxiway turns and for runway U-turn through use of cameras (correct visual
cues acquired) has been confirmed by A340-600/777-300 experience to give excellent pilot
skills.
Taxiway and shoulder
— Aerodrome taxi navigation guidance: A precision type guidance system based on
differential GPS or visual sensors can give tracking guidance to an accuracy of less than one
m from the taxiway centre line. This can prevent inadvertent deviation such as under poor
visibility.