PASS project final report.

The Work Area 1 Final Report summarises the PASS monitoring activity. It reports on the sources and tools used for the data collection, explains how the various analyses were performed, provides the results of the analyses and outlines how those results will be used in the next PASS activity: the modelling phase.

This report provides analysis of RA downlink data from six Mode-S radars with a coverage including most of the European core area. The data were collected from September 2007 to March 2008, representing more than 1,300,000 flight hours.

The simulations conducted within WA2 of PASS have led to the development of performance metrics that would quantify the qualitative requirements expressed in EUROCONTROL Specification of Short-Term Conflict Alert. Depending on the exact strategy adopted by an ANSP with regard to the role of its STCA system (i.e. focused on “collision avoidance” or on “separation protection”), appropriate thresholds for these metrics can be established so as to set up minimum performance requirements for this STCA system.

This document provides some elements on the role of STCA and ACAS as safety nets in the current ATM environment, and on the evaluation of their performances. It recaps the outcome of the “IAPA – ASARP Methodology for Safety net Assessment – Feasibility Evaluation” (I-AM-SAFE) study and gives some insight into the simulation process that has been set up to adapt the ACAS encounter model-based methodology to the context of STCA. Additionally, the document contains the most significant results of the evaluation of STCA performance that has been conducted on a number of operational scenarios using simple assumptions at this stage, yet representative of current STCA operation in Europe.

The operational safety assessment seeks to identify the errors and malfunctions of the ATM system which are related to the functioning of STCA or to the interoperability aspects of STCA and TCAS analyzed as an overall concept. The identified hazards are then used to derive safety objectives, as a first step for the identification of Safety Requirements and Recommendations in the final phase of the PASS project.

The objective of this operational safety assessment Interim Report in Work Area 4 is to address the “failure” approach. The “success” approach (prevention of accidents) will be covered during the PASS fast-time simulations that will take place in Phase 3, as it is intended: to compare the “initial” severity of the encounter without the effect of the controller’s instruction prompted by STCA and the “final” severity resulting from the pilot’s response to the controller’s instruction.

This document provides a synthesis of the factors influencing the STCA and TCAS interaction and derives guidelines for an overall consistent concept of operations for independent and compatible STCA and TCAS systems.

This document describes candidate safety and performance requirements relevant to the operation of STCA. It builds on the results of the model-based Performance Evaluation (WA2) and of the Operational Safety Assessment (WA4).