Agenda Item 6 GNSS Operations Ross Bowie, NAV CANADA Rapporteur, Operational WG Navigation Systems Panel Thank you… Good morning… I am ... and member of ATMCP. The complete title of the presentation is: Need for the development of performance criteria and the concept of required total system performance (RTSP): It relates directly to the topics to be addressed under agenda item 3 of the Conference, but you will easily see connections with virtually all agenda items. Performance, including safety, provides a vehicle to discuss all aspects of Air Navigation from the planning stages to the monitoring of actual service delivery.

Outline Meeting performance requirements Basic GNSS operations SBAS operations GBAS operations Implementation issues GNSS evolution

Achieving Performance Accuracy - easily achievable, demonstrated for Cat III Integrity (alert limits match operation) - achievable, demonstrated for APV - precision approach levels challenging - conservative integrity design decreases availability

Achieving Performance (cont’d) Continuity - achievable via redundancy, demonstrated Availability - achievable, high availability challenging for the most demanding operations

Basic GNSS Operations GPS and Basic GNSS receiver fault detection (RAIM) en-route and terminal RNAV RNAV non-precision approach (lateral guidance only) RAIM requires extra satellites in view need to retain ground aids and avionics RAIM prediction & NOTAMs

SBAS Operations Core satellite constellation(s), geostationary satellites, ground network, SBAS receiver SBAS receiver uses fault detection and exclusion in absence of SBAS signal High availability of integrity for en route, terminal, non-precision approach and approach with vertical guidance (APV)

SBAS Implementation SBAS status (IPs/17,32,50,58) WAAS (USA) commissioned July 2003 EGNOS (Europe), MSAS (Japan) to be commissioned 2004-2005 GAGAN (India) under development, 2005-2006 States to ensure data integrity for SBAS approaches

SBAS-based APV APV compared with non-precision approach vertical guidance = stabilized descent & integrity no need for guidance system at airport APV compared with Cat I precision approach lateral approach design identical vertical design slightly more restrictive lowest Decision Altitude 75m (250 ft) less ground infrastructure required (e.g. lighting)

Performance Comparison Horizontal & Vertical Integrity Alert Limits LNAV/VNAV (H=556m) - SBAS* or (GPS + Baro VNAV) *with V=50m APV-I (H=40m, V=50m) - SBAS APV-II (H=40m, V=20m) - SBAS [Cat I (H=40m, V=12m ) - GBAS or future SBAS]

GBAS Status & Operations Core satellite constellations, ground station at airport, VHF datalink, GBAS receiver GBAS functionality in multi-mode receiver (MMR) Precision approach capability Cat I GBAS planned for 2006 (IP/16) Cat II/III issues studied (WP/20)

Implementation Issues GNSS Manual (IP/14) provides guidance on implementation aspects Planning & Organization GNSS implementation team Procedures development design criteria & flight inspection Airspace considerations (RNAV operations)

Implementation Issues (cont’d) Aeronautical Information Services surveys (WGS-84) and database GNSS status monitoring and NOTAMs (IP/71) Certification & operational approvals system safety analysis spectrum protection (unintentional interference) avionics certification & integration

GNSS Vulnerability (WP/17) Signal interference issues good control of the electromagnetic spectrum to reduce the risk of unintentional interference intentional interference is the key concern threat analysis required for airspace concerned

Mitigation Techniques To account for likelihood and impact of outage To ensure safety and reduce economic impact (not worth interfering) Suitable combination of: integrated on board systems (inertial) pilot and ATC procedures (radar/non-radar) back-up terrestrial navaids where necessary DME to support RNAV strategically located ILS to support landing

Future operational enhancements GBAS for Cat II/III approach & surface operations Next generation satellite constellations Galileo, GPS III, GLONASS-K better resistance to interference improved performance (Cat I SBAS likely) reduced complexity of augmentations Optimum combinations of elements & signals to be established (WP/18)

Summary Basic GNSS is in widespread use SBAS is being introduced RNAV and better non-precision approaches SBAS is being introduced APV, increased availability, reduced need for ground aids GNSS evolution operational enhancements when new signals available and fleets equipped take advantage of GNSS now, monitor future developments and plan accordingly