Appendix A A-2 A.3.3 ABAR generating systems are designed to be used on aircraft that utilize landing performance data derived in accordance with AC 25-32; International Civil Aviation Organization (ICAO) Doc 10064, Aeroplane Performance Manual; or other equivalent standards.
A.4 Acceptance Criteria for ABAR S ystems.
A.4.1 ABAR systems are not required for certification of transport category aircraft and their intended function is not a regulatory requirement.
A.4.2 Operators who utilize ABAR related technology to transmit information with the label “ABAR,” should only do so if it can be determined that the system meets its intended function and complies with a minimum engineering standard published for such a system.
Entities seeking such a determination for an ABAR producing system should contact their designated FAA representative for guidance.
A.4.3 ASTM E3266 provides a suitable acceptance criterion for operators wishing to transmit information from an ABAR system.
A.5 Confidence of Reports.
A.5.1 ABAR generating systems may rely on aircraft data that is inferred from other sources to calculate the required values. Because these systems may not rely on sensors taking direct measurements of certain values, these systems cannot be calibrated in a manner similar to other flight deck indicators. Therefore, while the ASTM standard sets minimum levels of accuracy and precision for these systems, it should be recognized that there exists a statistical difference between what a system calculates and what a theoretical “real” value could be. For that reason, these systems are described as having a “confidence factor.”
A.5.2 ABAR generating system standards require the systems to demonstrate a confidence factor of 95 percent that the system will fall within one level of braking on the Runway Condition Assessment Matrix (RCAM) five level scale (i.e., good, good to medium, medium, medium to poor, and poor.)
A.6 Development of Operational Guidelines. Operators who utilize an ABAR system to provide and/or use such reports should develop operational guidelines and flightcrew training. This should include submitting Pilot Reports (PIREP) based on ABAR information after landing as well as the use of ABAR reports during TOA assessments.
ABAR systems whose intended function entails timely recognition from the flightcrew should comply with AC 25.1322-1, Flightcrew Alerting.
Note: Pilots and operators need to understand that an ABAR is a decision support tool rather than a decision-making tool. Pilots should use an ABAR as one piece of information along with the current weather, runway surface conditions, and other factors to make the decision as to whether or not it is safe to land.
Appendix A A-3 A.6.1 The following guidelines are considered acceptable for the operational use of information provided by ABAR systems:
1. When an ABAR confirms the accuracy of the Runway Condition Code (RwyCC)
(i.e., both values are the same), the time of arrival (TOA) landing distance assessment should be based on this confirmed value; and
2. When an ABAR and the reported RwyCC disagree (i.e., one value indicates worse runway conditions than the other), the TOA landing distance assessment should be based on the worse (most conservative) report.
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