Appendix B B-9 the second aircraft becomes a threat, the RA will be modified to provide separation from that aircraft.).
h. The consequences of not responding to an RA and maneuvering in the direction opposite to the RA.
i. A prompt response is made when a climb RA is generated while the aircraft is at the maximum altitude.
j. If applicable, compliance with an Autopilot (AP) RA and demonstration of the ability to return to course, address mode conflict issues, etc.
B.3.3 C haracteristics of Training Equipment Suitable for Maneuver Training .
B.3.3.1 Acceptable Characteristics. Flight Training Devices (FTD), simulators, and computer-based trainers should have certain characteristics to be effective.
This is due to the interactive nature of ACAS II, the variety of encounter scenarios possible, the immediate and standardized pilot response required, and the instant and correct display interpretation that is necessary. Thus, training equipment used for ACAS II flight training should have the following characteristics:
• The ability to functionally represent traffic displays, controls, indications, and annunciations;
• The ability to depict selected traffic encounter scenarios, including traffic display and audio advisories;
• The ability to show proper ACAS II reaction to depicted scenarios and advisories; and
• The ability to interactively respond to pilot inputs regarding ACAS II advisories, including responses to RAs displayed on relevant vertical speed and pitch indicators.
B.3.3.2 Simulator and ACAS II Fidelity. For a particular ACAS II, one may accomplish maneuver training in ACAS II-qualified simulators or FTDs that represent the specific aircraft or an aircraft that has similar characteristics. For the purposes of ACAS II maneuver training, simulators or FTDs may use simplified ACAS II algorithms or displays and do not require ACAS II logic or an ACAS II processor. Traffic displays do not have to be identical but should be functionally equivalent to the specific aircraft in use by the operator.
B.3.3.3 FTD or Simulator Approval. The National Simulator Program (NSP) qualifies Flight Simulation Training Devices (FSTD) as meeting 14 CFR part 60 requirements, and the Principal Operations Inspector (POI) approves them for use in a training program. Any one or combination of the following ACAS II-qualified devices may be used:
Appendix B B-10
• Level A through D simulators,
• Level 4 through 7 FTDs, or
• Other ACAS II training devices that are shown to be suitable for ACAS II training and are approved by the POI.
Appendix C C-1 APPENDIX C. SAFETY MANAGEMENT SYSTEM (SMS) CONSIDERATIONS FOR
ACAS II TA-ONLY MODE OPERATIONS C.1 SMS. Per AC 120-92, Safety Management Systems for Aviation Service Providers, the defining characteristic of an SMS is that it is a Risk-Based Decision-Making (RBDM) system. An SMS is built by structuring the safety management of an operator around four components: safety policy, Safety Risk Management (SRM), Safety Assurance (SA), and safety promotion. Organizations that are required to comply with 14 CFR part 5 should use the SRM and SA components of an SMS to perform RBDM and monitoring on ACAS II use and the policies and procedures thereof. All operators are recommended to implement a formal process for gathering feedback on ACAS II use. This includes any irregularities, malfunctions, and lessons learned. An operator is recommended to use this formal process during design, installation, modifications, or improvements to procedures and/or training. In this appendix, an example will be discussed for SMS consideration for ACAS II TA-ONLY mode operations.
C.1.1 SRM. S RM provides a system for identifying hazards and mitigating risk based on a thorough understanding of the organization’s systems and their operating environment.
C.1.1.1 W hen SRM is needed, an operator should apply SRM to the implementation of new systems, revision of existing systems, development of operational procedures, and identification of hazards or ineffective risk controls through the SA process.
C.1.1.2 SRM Processes. There are five processes necessary to control and mitigate risk: system analysis, hazard identification, safety risk analysis, safety risk assessment, and safety risk controls.
Example: SRM is recommended for an operator of an ACAS II-equipped aircraft if the operator were to consider advising their flightcrews to select TA-ONLY mode for approach at a specific airport. This procedure removes a risk control. A risk control is a means to reduce or eliminate the effects of hazards (in this case, the risk control offered by the Traffic Advisory (TA)/Resolution Advisory (RA) mode of the ACAS II). SRM is recommended to describe the system; identify the hazards; and analyze, assess, and control the risk.
C.1.1.3 System analysis and hazard identification proactively identify and address potential problems before the new or revised systems or procedures are put into place. In the example, the use of TA-ONLY mode presents hazards that an operator should identify for the system that they operate. The knowledge gained in the system analysis and subsequent risk analysis will later be used to develop a mitigating strategy.
C.1.1.4 Safety risk analysis estimates the severity and likelihood of a potential accident due to exposure to an identified hazard (in this case, a hazard associated with the selection of TA-ONLY mode on approach).
Appendix C C-2 C.1.1.5 Safety risk assessment is completed once the risk has been analyzed. The operator should assess whether the risk is acceptable. A common tool used in risk assessment decisions is a risk matrix. A risk matrix enables an organization to assess risks, compare potential effectiveness of proposed risk controls, and prioritize risks where multiple risks are present by providing a way to integrate the severity of the outcome and the probability of occurrence.
If the risk is found to be acceptable, then the system may be placed into operation and monitored in the SA process. If the operator decides the risk is not acceptable, the operator will need to follow the next step in SRM, where an operator will develop risk controls.
C.1.1.6 Safety risk control is conducted after hazards and associated risks are fully understood. Risk controls are utilized to reduce the likelihood or severity of a hazard and mitigate the associate risk. Risk controls should be designed for risks that are deemed unacceptable.
C.1.2 SA. S A works in partnership with SRM. In SA, the process continues with measuring and monitoring the performance of the system operation, with the designed risk controls in place. SA processes are a means of assuring the safety performance of the organization, keeping it on track, correcting it where necessary, and identifying needs for rethinking existing processes. SA requires monitoring and measuring safety performance of operational processes and continuously improving the level of safety performance. Strong SA processes will yield information used to maintain the integrity of risk controls. SA steps include system monitoring, data acquisition, analysis of data, system assessment, and corrective action. Data acquisition involves a variety of sources, including continuous monitoring, internal audits (by operational departments), internal evaluations (by other departments within the company), external auditing (third-party audits), investigations, and employee reporting and feedback systems.
Example: A n SA process is recommended for an operator of an ACAS II-equipped aircraft if the operator is evaluating and monitoring the use of TA-ONLY mode for approach at a specific airport.
C.1.2.1 Continuous Monitoring. One source of data may be continuous monitoring. In the monitoring of the operational environment and operational processes, it comes to the attention of the operator that the flightcrews are not complying with the company policy.
C.1.2.2 Analysis of Data. Analysis involves examining data acquired from various sources to make inferences about the effectivity of the risk controls.
C.1.2.3 Safety Performance Assessment. In the assessment step, collected safety performance data has been analyzed, and the results are used for informed decision making. The assessment process is where these decisions are made.
In this example, conformity with the risk controls appear to be unsatisfactory, and desired results are not being obtained. If this occurs, the SRM processes would be triggered.
Appendix C C-3 C.1.2.4 The final step within SA is continuous improvement. This process is designed to ensure that the operator is correcting substandard safety performance identified during the safety performance assessment to continuously improve safety performance.
C.2 TA-ONLY Considerations for SMS.
C.2.1 RAs can occur while aircraft are separated in accordance with established standards.
Even when closely spaced parallel approach procedures are correctly applied, unwanted RAs may occasionally occur. However, the safety benefit provided by ACAS II takes precedence over an occasional unwanted RA. Additionally, there is always the possibility another aircraft that is not associated with the parallel approach procedure becomes a threat. The term “nuisance alert” is commonly used to describe an RA when it is not desired. This is a misnomer; ACAS II is operating as designed, and flightcrews should comply with the RA.
C.2.2 Flight Standards (FS) has identified several considerations associated with operating ACAS II in TA-ONLY mode. An operator is advised to consider the following list during the SRM process. This list is nonexhaustive, and additional unique considerations, hazards, or ineffective risk controls are to be identified that are applicable to the environment of an individual operator:
1. Likelihood of aircraft positioned so that they are at risk for a collision, including uncontrolled/noncompliant (with Air Traffic Control (ATC) clearances or instructions) traffic.
2. Pilot reaction time to establish visual contact with the intruder aircraft.
3. Pilot reluctance to comply with an RA, in TA/RA mode, due to complacency associated with unwanted or expected RAs.
4. Difficulty of visually acquiring and monitoring an intruder aircraft in meteorological conditions that reduce the ability to accurately judge the flight path of the intruder aircraft (e.g., sun angle, haze, lack of defined horizon, and nighttime).
5. Difficulty of visually acquiring and monitoring an intruder aircraft on a parallel or converging approach course (i.e., intruder aircraft may possibly be adjacent or behind the flight path of own-ship).
6. Difficulty of ascertaining the flight path of the intruder aircraft (e.g., visual perception of the encounter may be misleading).
7. Difficulty understanding the flight trajectory of the traffic on an adjacent final approach segment or elsewhere due to traffic display bearing accuracy limitations.
8. In low closure rate scenarios (e.g., Closely Spaced Parallel Operations (CSPO)) with TA-ONLY mode selected, after receiving the initial TA, no auditory ACAS II advisories will be generated after the initial TA. The flightcrew may, over time, have reduced awareness of the flight path of the intruder aircraft.
9. Increased flightcrew workload during the approach phase (e.g., selecting TA-ONLY mode and monitoring the flight path of all intruder aircraft.)
Appendix C C-4
10. Increased flightcrew workload during a missed approach/go-around/balked landing
(e.g., selecting TA/RA mode and monitoring the flight path of possible adjacent missed approach traffic).
11. Lack of RA maneuver generation when TA-ONLY mode was selected on an approach, and the flightcrew fails to return to TA/RA mode in the event of a missed approach/go-around/balked landing.
12. If a flightcrew does not intend to respond to an RA and operates in TA-ONLY mode, other ACAS II-equipped aircraft operating in TA/RA mode will have maximum flexibility in generating RAs to resolve encounters.
Appendix D D-1 APPENDIX D. ACAS RESOLUTION ADVISORY (RA) REPORT Your participation in the reporting of ACAS events is essential to the success of ongoing evaluation of ACAS performance. Use the following information to guide your reporting of the ACAS event through the pilot report options outlined in this AC.
Reporting Pilot: ________________ Date: _____/_____/_____ Time: __________ UTC Origin: _________ Destination: _________ Call Sign: __________ A/C Type: _________ Registration Number: __________ Transponder Code: ____________ ATC Control Name: ____________ ATC Control Frequency: _______________ Actual Altitude: ___________ Cleared Altitude: ___________ Own Position: _______________________________ (Lat./Long. or Nav Aid/Radial/Distance) Phase of Flight: Departure (Takeoff to 10,000 feet) Climb (10,000 feet to Cruise) Cruise Descent (Cruise to 10,000 feet) Holding Pattern Approach (Below 10,000 feet) THREAT AIRCRAFT (if known) Call Sign: _____________ A/C Type: Commercial General Aviation Military Other Make/Model: _____________ Actual Altitude: ___________ Cleared Altitude: ___________ Did you have the aircraft in visual contact? Yes No If yes: Before TA / After TA. Before RA / After RA.
Was a TA generated? Yes No Were multiple TAs generated against the same intruder? Yes No Initial RA Generated: Descend, Descend Climb, Climb Monitor Vertical Speed Climb, Crossing Climb Descend, Crossing Descend Maintain Vertical Speed, Maintain Maintain Vertical Speed, Crossing Maintain Adjust Vertical Speed, Adjust ________ feet/minute Level Off, Level Off Did the initial RA change to any of the following?
Adjust Vertical Speed, Adjust Level Off, Level Off Increase Climb Increase Descent Climb, Climb NOW Descend, Descend NOW Descend, Descend Climb, Climb Range to threat aircraft at RA? __________ Bearing to threat aircraft at RA? ___________ Relative altitude of threat aircraft at RA? ____________feet Estimated Closest Proximity: Range ____________NM Altitude ____________NM Your response to the RA was: Climb Descend Change in Vertical rate Level Off Turn No Response No Response Necessary Was the event reported to ATC? Yes No Did ATC provide traffic information on the threat aircraft? Before RA After RA No Did the RA conflict with ATC instructions? Yes No If you did not comply with the RA, please explain why:
______________________________________________________________________________ ______________________________________________________________________________
REMARKS (please provide comments/concerns on this encounter):
______________________________________________________________________________ ______________________________________________________________________________
Advisory Circular Feedback Form If you find an error in this AC, have recommendations for improving it, or have suggestions for new items/subjects to be added, you may let us know by contacting the Flight Technologies and Procedures Division at 9-AWA-AFS400-Coord@faa.gov or the Flight Standards Directives Management Officer at 9-AWA-AFB-120-Directives@faa.gov.
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