EXECUTIVE SUMMARY:
The FLYSAFE Project is concerned with the development of a prototype Next Generation Integrated Surveillance System (“NG-ISS”). The Traffic functionality of the NG-ISS groups several air-traffic awareness and alerting subsystems with response-times ranging from immediate reaction (safety net functions such as TCAS / ACAS), through tactical alerting systems (e.g. airport surface movement alerting) to inputs for strategic decision and planning aids. The use of ADS-B data is assumed throughout Traffic functionality and selected Airborne Separation Assistance System (ASAS) Package 1 applications are expressly included in the Traffic functionality.
This report documents the results of WP 3.1.5, “Safety Implications of ASAS Package 1 Applications”. The objectives of the work package are to:
- Identify a set of ASAS potential safety issues;
- Analyse this information to identify trends & patterns;
- Perform a more detailed analysis for selected ASAS applications;
- Review and study the safety impact of each issue in terms of likelihood and severity;
- Document safety implications and trends identified during the analysis.
The ASAS Package 1 Applications selected for more detailed analysis are:
- The Airborne Spacing Application – Sequencing and Merging (ASPA-S&M),
- Airborne Traffic Situation Awareness - In-Trail Procedure (ATSA-ITP)
- Airborne Traffic Situation Awareness on the airport SURFace (ATSA-SURF)
However, a survey of all ASAS Package 1 applications has been performed, based on information available to the partners involved in the work package, and is documented in Chapters 3 to 13 of the report. Identified key safety issues and safety-related trends are discussed in Chapter 14, “Review of Key ASAS Safety Issues”.
The review of safety assessments has shown that the Airborne Traffic Situation Awareness (ATSA) applications share a set of safety issues in common, even though individual applications are implemented in different phase of flight. Further studies are required in order to mitigate key hazards and to specify the impact of ATSA on the ground ATC. On the other hand, no blocking issues have been identified, mainly because all of the different ATSA applications aim at improving existing procedures.
In ASAS spacing (e.g. ASPA-S&M), four mutual “major” or “hazardous” hazards have been found through the cross-check of safety assessments carried out by the ASAS Requirements Focus Group (RFG) and the Large Scale European ADS pre-implementation Programme (SEAP). The following operational hazards have the most severe consequences if they occur and are undetected:
- Error in flight parameter adjustment by pilot to control the airborne separation,
- Unexpected manoeuvre of the crossed / target aircraft during the execution,
- Erroneous pilot checking of separation after a manoeuvre
In the case of other ASAS applications (ASPA-C&P, ATSA-ITP), the analysis showed that some of the ASPA-S&M hazards are applicable to, or have counterparts with, the hazards found in ATSA-ITP and ASPA-C&P. For example: loss of ADS-B capability or undetected non-execution of the relevant manoeuvre. With regard to ADS-B applications, safety analyses are still ongoing and some of the applications are immature; no solid safety recommendations are currently available other than for the ADS-B-NRA application.
The objectives of the work package have been achieved with the review of available safety study results and the identification of the most significant hazards for Package 1 applications, with a particular focus on those applications directly relevant to the NG-ISS, i.e. ASPA-S&M and ATSA-SURF.
For further information please contact:
Mr. Derek Jordan:
derek.jordan@baesystems.com