investigating techniques by which pilots could provide airborne separation
assurance have successfully demonstrated that automatic dependent surveillance
broadcast (ADS-B) can be used for specific aerial co-ordination manoeuvres.
flights were conducted under the More Autonomous Aircraft in the Future Air
Traffic Management System (MA-AFAS) programme – a joint European Union effort
between avionics providers and air traffic control specialists.
is focused on three main components – taxi management, cockpit display of
traffic information, and four-dimensional trajectory operations – as part of a
larger overall programme aimed at examining complete gate-to-gate advanced
flight management concepts.
self-separation trials fall under the ‘cockpit display’ section of the project;
pilots would use ADS-B displays to monitor surrounding airborne traffic. This
section of the project envisaged the use of specially-equipped BAC One-Eleven
aircraft from UK research group QinetiQ and a twin-engined VFW614 test-bed
aircraft from the German DLR aerospace research facility.
flights in the vicinity of Rome demonstrated that ADS-B could be used for key
sequencing and conflict-avoidance manoeuvres such as ‘merge behind’ and ‘pass
behind’ in which one aircraft maintains a fixed separation distance from the
other – in this case, 6nm (11km) – while operating at the same flight level.
‘merge behind’ technique involves aligning an aircraft’s flight path with that
of a target aircraft over a fixed waypoint, such that the two emerge in train,
while a ‘pass behind’ instruction requires one aircraft to deviate from its
track to pass behind a crossing aircraft, before re-joining its original
concept, says the MA-AFAS project team, could be extended to vertical crossing,
overtaking and other similar movements involving pilots’ adjusting flight paths
in relation to other traffic.
still a controversial subject, autonomous separation by pilots is seen as a way
of reducing controller workload while increasing pilots’ situational awareness
and providing greater airspace flexibility.
Systems’ avionics division is participating in, and part-funding, the MA-AFAS
programme alongside 18 other contributors including air traffic control systems
manufacturers, research groups and air traffic services providers.