Appendix 1 ADS-B operations within the Singapore FIR, refer to Civil Aviation Authority of Singapore (CAAS) AIC 14/10, Introduction of Automatic Dependent Surveillance-Broadcast (ADS-B) Out Services within Parts of the Singapore FIR.
l. Vietnam. Authorization, per OpSpec/MSpec/LOA A153, is required. A153 is required for all U.S.-registered aircraft flying over ATS routes L625, M771, N892, L642, M765, M768, N500, and L628 at or above FL290 within the Ho Chi Minh FIR. For additional information regarding ADS-B operations within the Ho Chi Minh FIR, refer to Civil Aviation Authority (CAA) of Vietnam AIC 03/13, Implementation of ADS-B within Ho Chi Minh FIR.
m. Additional Regions. As additional regions are implementing ADS-B, U.S. aircraft operators are advised to monitor the regions applicable to their operation for any changes related to ADS-B requirements and to comply with Title 14 of the Code of Federal Regulations (14 CFR) part 91, § 91.703. Normally, these types of advisories are transmitted through State AIPs and/or AICs.
4. AUTHORIZATION TO CONDUCT ADS-B OPERATIONS OUTSIDE OF U.S.-DESIGNATED AIRSPACE WHERE STATE OF REGISTRY OPERATIONAL APPROVAL IS REQUIRED. FAA authorization is required for all U.S. aircraft operators seeking access to foreign ADS-B airspace where State of Registry operational approval is required. This appendix provides guidance to operators on the process and documentation required when requesting issuance of this authorization.
NOTE: For FAA authorization, refer to FAA Order 8900.1, Flight Standards Information Management System (FSIMS), Volume 3, Chapter 18, Section 3, OpSpec/MSpec/LOA A153.
a. Initial Request for Authorization. U.S. aircraft operators seeking to conduct ADS-B Out operations outside of U.S.-designated airspace must first contact their assigned FAA office to indicate their intent. At the time of the operator’s initial request, the FAA will provide the operator with an OpSpec/MSpec/LOA A153 Application Checklist (found in the A153 guidance section of the Web-based Operations Safety System (WebOPSS) or at http://www.faa.gov/nextgen/programs/adsb/ under Quick Links), which must be completed and included with attached support documents when submitting a formal request for authorization.
b. Required Documentation for Submission of Formal Request.
(1) Documentation Guidance. The following paragraph provides general guidance on the documentation required for submission of a formal request for issuance of this authorization.
At the discretion of the operator’s assigned principal inspector (PI), additional information may be required based on any unique aspects of specific operations. The operator must submit a letter of request for issuance of authorization to the assigned PI. The letter of request should include the following information:
(a) Type of aircraft (make, model, and series (M/M/S)).
(b) Airplane registration number(s) and serial number(s).
Appendix 1
(c) Make, model, and part number of the ADS-B transmitter and positioning source installed on each airplane.
(d) Areas of intended operation.
NOTE: The guidance contained in subparagraph 4b of this appendix will also be annotated on the OpSpec/MSpec/LOA A153 Application Checklist provided to the operator by the applicable FAA field office.
(2) Airplane Flight Manual (AFM) Compliance Documentation. The operator will provide a copy of the AFM, Aircraft/Airplane Flight Manual Supplement (AFMS), Airplane Operations Manual (AOM), or pilot’s operating handbook (POH), as appropriate, which states that the aircraft’s ADS-B Out system complies with any of the following:
(a) Section 91.227.
(b) The current edition of AC 20-165, Airworthiness Approval of Automatic Dependent Surveillance Broadcast (ADS-B) Out Systems.
(c) European Aviation Safety Agency (EASA) Acceptable Means of Compliance (AMC) 20-24, Certification Considerations for the Enhanced ATS in Non-Radar Areas using ADS-B Surveillance (ADS-B-NRA) Application via 1090 MHz Extended Squitter (until rescinded).
NOTE: The following is an example of an AFM statement for an ADS-B system that complies with § 91.227: “The installed ADS-B Out system has been shown to meet the equipment requirements of 14 CFR § 91.227.”
NOTE: ADS-B Out systems approved per previous versions of AC 20-165 must have any variances, with subsequent revisions of that guidance, resolved through the FAA/manufacturer issue paper process. Such systems do not require revision of existing AFM, AFMS, AOM, POH, Flight Operations Manual (FOM), or equivalent AC 20-165 compliance statements.
NOTE: The requirements in this appendix meet all of the operational, training, and maintenance considerations of AMC 20-24.
(3) Proposed Operations Area. A copy of OpSpec/MSpec B050, Authorized Areas of En Route Operation, Limitations, and Provisions, annotating the authorized en route areas where OpSpec/MSpec/LOA A153 will be used (not applicable to part 91 operators).
(4) Part 91 Operators. A statement that the operator’s pilots have knowledge of current air traffic ADS-B directives for the intended areas of en route operation and will comply with § 91.703.
(5) OpSpec/MSpec/LOA A153. A copy of the completed OpSpec/MSpec/LOA A153, as applicable.
Appendix 1 NOTE: The local Flight Standards Service (AFS) field office will conduct a review of the applicant’s submitted proposal using the OpSpec/MSpec/LOA A153 Application Checklist. When compliance with all applicable requirements has been demonstrated, the PI will issue A153.
Page 5 (and 6)
Appendix 2 APPENDIX 2. ADS-B IN-TRAIL PROCEDURE
1. PURPOSE. This appendix provides a description of the Automatic Dependent Surveillance-Broadcast (ADS-B)-enabled In-Trail Procedure (ITP) and guidance to operators seeking Federal Aviation Administration (FAA) authorization to conduct ITP operations.
2. BACKGROUND. The ITP is designed primarily for use in nonradar oceanic airspace to enable appropriately equipped ADS-B In aircraft to perform flight level (FL) changes previously unavailable with procedural separation minima applied. The improved traffic information available to ADS-B In-equipped aircraft allows ITP maneuvers to occur safely with reduced separation minima applied. ITP will enable flightcrews to execute FL changes to improve ride comfort, avoid weather, or obtain more favorable winds to improve fuel economy and arrival times.
a. ITP Scenario. Appendix 2, Figure A2-1, Reduction of Aircraft Separation Minima with In-Trail Procedure, illustrates a basic ITP scenario. The ITP aircraft (blue) wishes to climb from FL340 to 360 between two reference aircraft (red) where procedural separation minima is applied. Using onboard ADS-B In and ITP equipment, the ITP aircraft can determine if the necessary criteria can be met and, if so, request air traffic control (ATC) approval to execute the desired FL change using reduced separation minima between the two reference aircraft.
b. ATC Responsibility. ATC maintains separation responsibility throughout the ITP maneuver, and resumes the appropriate separation minima at its completion. The reduced ITP separation may only be applied between a qualified ITP aircraft and no more than two reference aircraft for the duration of the maneuver. Reference aircraft do not require ADS-B In equipment and are only required to be transmitting an ADS-B Out signal of sufficient quality.
FIGURE A2-1. REDUCTION OF AIRCRAFT SEPARATION MINIMA WITH
IN-TRAIL PROCEDURE
3. ITP TERMINOLOGY.
a. Closing Groundspeed (GS) Differential. The difference between the ITP aircraft’s GS and a reference aircraft’s GS that results in a reduction of the ITP distance.
b. Closing Mach Speed Differential. The difference in Mach speed between the ITP aircraft and the reference aircraft that results in a reduction of the ITP distance.
FL360 FL340 FL350
ALLOWED ITP CriteriaITP Criteria ITP Aircraft Reference Aircraft (ADS-B Out required) ADS-B not required Desired Altitude Procedural Separation FL360 FL340 FL350
ALLOWED ITP CriteriaITP Criteria ITP Aircraft Reference Aircraft (ADS-B Out required) ADS-B not required Desired Altitude FL360 FL340 FL350
ALLOWED ITP CriteriaITP Criteria FL360 FL340 FL350
ALLOWED ITP CriteriaITP Criteria ITP Aircraft Reference Aircraft (ADS-B Out required) ADS-B not required ITP Aircraft Reference Aircraft (ADS-B Out required) ADS-B not required Desired Altitude Procedural SeparationProcedural Separation Page 1
Appendix 2
c. ITP Aircraft. An aircraft operated by a flightcrew authorized to conduct an ITP.
d. ITP Criteria. A set of conditions that must be satisfied prior to initiating or executing an ITP clearance.
e. ITP Distance. The distance between the ITP aircraft and reference aircraft as defined by the difference in distance to an aircraft calculated common point along a projection of each aircraft’s track in front of or behind the aircraft, as appropriate. (See Appendix 2, Figure A2-2, In-Trail Procedure Distances Illustrated.) For the case where aircraft are on parallel tracks, the ITP distance is measured along the track of one of the aircraft using its calculated position and the point abeam the calculated position of the other aircraft. This measurement technique is similar to the method described in the International Civil Aviation Organization (ICAO) Doc 4444, Procedures of Air Navigation Services—Air Traffic Management (PANS-ATM), section 5.4.2.6.4.
f. ITP Equipment. The onboard avionics required to support an ITP.
g. Reference Aircraft. Aircraft (no more than two) transmitting valid ADS-B data that meet specified criteria and are referenced as part of an ITP clearance request to ATC.
Appendix 2 FIGURE A2-2. IN-TRAIL PROCEDURE DISTANCES ILLUSTRATED
4. ITP CONCEPT. The ITP concept is based on the aircraft satisfying specific initial conditions and the flightcrew promptly and correctly executing the requested procedure once approved. The initial conditions are the ITP speed/distance criteria, the relative altitude criteria, the similar track criteria, and the closing Mach differential, as well as the accuracy and integrity of the ADS-B data transmitted from participating aircraft. (See Appendix 2, Table A2-1, In-Trail Procedure Initiation/Maneuver Criteria (Reference RTCA DO-312).) The procedure further requires that the ITP aircraft maintain constant Mach and climb or descend at a minimum of 300 feet per minute (fpm) during the maneuver. With these criteria, an ITP aircraft should never Page 3
Appendix 2 come closer than the 10-nautical-mile (NM) separation minimum to a reference aircraft while passing through their altitude(s).
a. ITP Distance and GS Differential Criteria. The initial distance criteria values, 15 NM and 20 NM, were selected so that when an FL change at 300 fpm and constant Mach number is maintained with the respective maximum 20 or 30-knot (kts) closing GS differential, the distance between the aircraft should not become less than the ITP minimum separation of 10 NM.
b. Relative Altitude Criteria. The reference aircraft may not be more than 2,000 feet above or below the ITP aircraft.
c. Similar Track Criteria. The ITP aircraft and any reference aircraft must be on similar tracks. Similar tracks are defined here as less than 45 degrees from one another.
(See Appendix 2, Figure A2-3, Similar Track.)
d. Mach Differential. In order to ensure an acceptable closure throughout the ITP maneuver, the controller may not issue an ITP clearance if the closing Mach differential is greater than 0.06 Mach. This Mach differential check accounts for potentially unsafe closure rates due to abnormal or adverse wind gradient conditions at the intermediate altitudes. The Mach number check may be achieved by:
• Using the cruise Mach numbers of the ITP and reference aircraft where the Mach number technique is being used;
• Requesting Mach numbers from the ITP and reference aircraft; or
• Any other methodology determined appropriate and acceptable by the regulatory authority and the air navigation service provider (ANSP).
e. ADS-B Data Quality Criteria. Only ADS-B Out aircraft broadcasting data of sufficient quality may be used as reference aircraft for ITP. Own-ship data quality must also be sufficient to ensure safe separation. The data quality criteria are:
• Position accuracy for ITP and reference aircraft—ITP and reference aircraft data with horizontal position accuracies of at least 0.5 NM (95 percent);
• Position integrity for ITP and reference aircraft—ITP and reference aircraft data with horizontal position integrity bounds of 1.0 NM at 1x10E-05; and
• Velocity accuracy for ITP and reference aircraft—ITP and reference aircraft data with horizontal velocity accuracies of at least 10 meters/second (m/s) (19.4 kts), 95 percent.
Appendix 2 FIGURE A2-3. SIMILAR TRACK
5. ITP DESCRIPTION. To properly conduct an ITP, a qualified flightcrew must use ADS-B In avionics specifically certified to assist in verifying the initial conditions and a graphical display to monitor the relative position(s) of nearby aircraft. The procedure will only be conducted in airspace with appropriately trained ATC personnel, ITP compatible automation, and approved ITP separation minima available. The following are the steps necessary to conduct an ITP:
a. Flightcrew Verifies Initial Criteria. Using approved avionics, the ITP flightcrew verifies that their own-ship and the reference aircraft meet initial qualifying criteria. The onboard ITP avionics will indicate to the flightcrew whether all initiation criteria are satisfied.
b. Flightcrew Requests ITP. If the criteria are satisfied, the flightcrew requests the ITP clearance using the appropriate phraseology. Direct Controller Pilot Communication (DCPC) is required; currently, only Controller-Pilot Data Link Communication (CPDLC) is being used in locations where ITP are approved. Preformatted messages for requesting and approving ITP have not yet been developed. Flightcrews must use standardized free text messages as described in Appendix 2, Table A2-2, Flightcrew Standardized Free Text Controller-Pilot Data Link Communication Message Set for In-Trail Procedure, and Table A2-3, Controller Free Text Controller-Pilot Data Link Communication Message Set for In-Trail Procedure, until further notice. It is essential that the correct message elements be included in the correct format to allow the controller or automation system to properly evaluate the request. Improperly formatted or incomplete requests may be unnecessarily denied.
NOTE: ATC must not issue an ITP clearance to any aircraft unless that aircraft has initiated the request.
c. Controller Issues Clearance. Upon receipt of an ITP request, the controller:
(1) Confirms the ITP aircraft and the reference aircraft are on the same track.
(a) Same-track criteria are not the same as the similar-track criteria, which are checked by the ITP aircraft flightcrew.
Appendix 2
(b) Same-track includes the concept of similar-track (i.e., ITP aircraft and reference aircraft are traveling in the same direction with less than a 45-degree relative track angle between the aircraft), but also includes a check on whether or not the lateral protection areas overlap
(e.g., lateral separation cannot be applied). This check can only be done by the controller who knows what separation standard is being applied between the aircraft.
(2) Confirms that no more than two reference aircraft have been identified in the request and are identified correctly; that is, that the Aircraft Identification (ACID) of each reference aircraft in the ITP request exactly matches the corresponding aircraft’s filed flight plan (FP).
(3) Ensures both the ITP aircraft and reference aircraft are not maneuvering and not expected to maneuver during the ITP.
NOTE: A change of course (only) to remain on the same route would not be considered a maneuver, provided the course change is less than 45 degrees and the aircraft remain in a same track configuration.
(4) Verifies that the closing Mach differential is no greater than 0.06 Mach.
(5) Verifies that there are no conflicts at the requested altitude.
(6) If appropriate, issues an ITP clearance.
d. Flightcrew Reassesses Criteria. Upon receiving the ITP clearance, the flightcrew confirms that all criteria are still satisfied. If the criteria are not satisfied or there has been a loss of traffic information, the flightcrew must immediately reject the ATC clearance and terminate the maneuver. Additionally, if the FL, reference aircraft, or type of maneuver (ITP versus standard FL change) does not exactly match their request or if the flightcrew receives an ITP clearance without requesting one, they must not perform the maneuver and should verify with ATC to confirm the clearance.
e. Flightcrew Executes ITP. If the criteria are still met, the flightcrew accepts the clearance and begins the requested climb or descent without delay. While executing the maneuver, the flightcrew is expected to maintain their flight-planned route, assigned Mach number (or current Mach, if none is assigned), and minimum Vertical Speed (VS) of 300 fpm and ensure they execute only the maneuver for which they have been cleared. The maneuver is complete once the flightcrew reports to ATC that they have reached the new FL.
NOTE: Once the ITP maneuver has been initiated, it must be completed.
Should reference aircraft data be lost or ITP display fail during the maneuver, the flightcrew should continue the maneuver to the assigned altitude using the appropriate Mach number and 300 fpm minimum VS.
Upon completion of the maneuver, notify ATC of the ITP data loss.
f. Approved ITP Variations. An ITP can be conducted with a maximum of two reference aircraft. The reference aircraft may not be more than 2,000 feet of altitude above or below the ITP aircraft, but there is no limit on the amount of altitude change the ITP aircraft Page 6
Appendix 2 may request. The reference aircraft both may be behind or ahead of the ITP aircraft or one may be ahead and one behind. Appendix 2, Figure A2-4, In-Trail Procedure Climb/Descent Variations, depicts the approved ITP variations.
g. Contingency Procedures. The ITP maneuver has been extensively tested both in flight and in computer simulations with consideration given to a variety of environmental and aircraft performance factors. A temporary breach of the 10-NM ITP distance does not constitute an inherently unsafe procedure and should not be the sole factor when considering abandoning the procedure. No new contingency procedures are prescribed for ITP. If, in the pilot’s judgment, the ITP maneuver (i.e., reaching the newly assigned altitude) cannot be successfully completed once the climb or descent has been initiated, he or she shall:
(1) Contact ATC and request an alternative clearance as soon as practicable given flightcrew workload and flight conditions.
(2) Inform ATC of any action the flightcrew is taking or requesting. Because of the many variables, the CPDLC message should be in the “free text” format.
(3) Comply with regional contingency procedures appropriate to the circumstances, or as listed in ICAO Doc 4444, Procedures of Air Navigation Services—Air Traffic Management (PANS-ATM), section 15.2.
h. ITP Distance. Except when one aircraft is directly in trail of another, the ITP distance is not the same as the direct line distance between those two aircraft. (See paragraph 3, ITP Terminology, for the exact description, and Appendix 2, Figure A2-2, for examples.) Since the ITP software will be designed to calculate and display ITP distance information, extensive training on the subject is not necessary. However, it is important to emphasize that range and ITP distance are different. Consequently, a lack of understanding could lead the flightcrew to misidentify the correct reference aircraft(s) when requesting an ITP clearance. Training should include examples of the various ITP distance geometries depicted in Figure A2-2.
(1) Lateral Traffic Filters. Some ITP avionics incorporate a lateral traffic filter. The function of the traffic filter is to eliminate any targets beyond a predetermined lateral distance of own-ship’s track from consideration as a potential reference aircraft. This is intended to prevent the flightcrew from misidentifying incorrect reference aircraft during their ITP request. The filter is most useful when in an organized track environment or where traffic may be on a parallel user-preferred route. Incorrect use may result in unnecessarily denied ITP requests. Training should include recommended technique for its use.
(2) ITP Initiation Criteria. Traffic displayed as an ADS-B In target may not be made available as a valid ITP reference aircraft because it does not meet one or more ITP initiation criteria. Some of the criteria, such as position accuracy, are not displayed to the flightcrew.
Training should include a discussion of the initiation criteria, which criteria are known to the flightcrew, and examples of when a displayed ADS-B In target is not an eligible ITP reference aircraft. See Appendix 2, Table A2-1, for ITP initiation criteria.
Appendix 2 FIGURE A2-4. IN-TRAIL PROCEDURE CLIMB/DESCENT VARIATIONS
6. AUTHORIZATION TO CONDUCT ITP. FAA authorization is required for all U.S. aircraft operators to conduct ITP operations using ADS-B In. This appendix provides guidance to operators on the process and documentation required when requesting issuance of this authorization.
NOTE: For FAA authorization, refer to FAA Order 8900.1, Flight Standards Information Management System (FSIMS), Volume 3, Chapter 18, Section 3, Operations Specification (OpSpec)/Management Specification (MSpec)/Letter of Authorization (LOA) A354, Automatic Dependent Surveillance-Broadcast (ADS-B) In-Trail Procedure (ITP).
NOTE: Operators may already hold other ADS-B In authorizations. There is no need to submit documentation for ITP requirements that duplicate specific requirements for previous ADS-B In authorizations. The ITP application may include references to those duplicate requirements instead.
a. Initial Request for Authorization. U.S. aircraft operators seeking to conduct ITP must first contact their assigned FAA office to indicate their intent. At the time of the operator’s initial request, the FAA will provide the operator with an ITP Application Checklist, which must be completed with attached supporting documents.
b. Required Documentation for Submission of Formal Proposal.
(1) Documentation Guidance. The following section provides general guidance on the documentation required for submission of a formal ITP proposal. At the discretion of the operator’s assigned principal inspector (PI), additional information may be required based on any Page 8
Appendix 2 unique aspects of their specific operation. The operator must submit a letter of request for issuance of authorization to the assigned PI. The letter of request should include the following information:
(a) Type of aircraft (make, model, and series (M/M/S)).
(b) ADS-B equipment complies with Technical Standard Order (TSO)-C195a, Avionics Supporting Automatic Dependent Surveillance-Broadcast (ADS-B) Aircraft Surveillance Applications (ASA), or as approved for ITP by the Administrator.
(c) Installation complies with the current edition of Advisory Circular (AC) 20-172.
(d) Manufacturer’s name of the ADS-B In software.
(e) Proposed region(s) of operation (not applicable to Title 14 of the Code of Federal Regulations (14 CFR) part 91 operations).
NOTE: The guidance contained in subparagraph 6b of this appendix will also be annotated on ITP Using ADS-B In Application Checklist provided to the operator by the applicable FAA field office.
(2) Airplane Flight Manual (AFM) Compliance Documentation. Operators must submit documentation that demonstrates that their aircraft have an ADS-B In system that meets the performance standards of TSO-C195a or as approved for ITP by the Administrator.
(3) Proposed Operations Area. Authorizations to conduct ITP will be limited to specific regions of the world where the ANSP offers ITP and those procedures are determined to be acceptable to the Administrator. Routes or airspace where ITP may be authorized will be published in Aeronautical Information Publications (AIP). Include in your request a description, by flight information region (FIR) and ANSP, of the operational areas where you propose to conduct ITP. If the operator holds an OpSpec/MSpec B050 authorization, a draft B050 paragraph that includes the operational areas where you propose to conduct ITP, including applicable notes, must be submitted.
(4) Operational Procedures. As applicable, company manuals must address any ITP-specific requirements of the proposed region(s) of operation.
(5) Operation Manuals and Checklists. The certificate holder/operator/program manager (as applicable) must submit information (e.g., Airplane Operations Manual (AOM) bulletin or equivalent) to the flightcrews describing ADS-B to include:
• ITP system description;
• Normal procedures;
• En route procedures using ITP;
• Communications; and
• Non-normal or contingency procedures.