Appendix 1 Surveillance-Broadcast (ADS-B) Operations Outside of U.S.-Designated Airspace, current edition;
(2) EASA 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, dated February 5, 2008;
(3) TCCA AC 700-009, Automatic Dependent Surveillance-Broadcast, current edition;
(4) NAV CANADA AIC 21/09, Air Traffic Flow Management in the Vicinity of Hudson Bay as a Result of Automatic Dependent Surveillance-Broadcast OUT Implementation, current edition;
(5) CASA CAO 20.18, Aircraft Equipment—Basic Operational Requirements, current edition;
(6) CASA CAO 82.5, Condition on Air Operators’ Certificates Authorising Regular Public Transport Operations in High Capacity Aircraft, current edition; and
(7) CAAS AIC 14/10, Introduction to Automatic Dependent Surveillance Broadcast (ADS-B) OUT Service within Parts of the Singapore FIR, current edition.
b. Additional Information. For additional information regarding specific NRA operations, contact the following organizations or individuals:
(1) Contact the Flight Technologies and Procedures Division (AFS-400) by phone at 202-385-4586 or by email at 9-AWA-AVS-ADS-Programs-AFS/AWA/FAA.
(2) For additional information on 14 CFR parts 121 and 135 special authorizations (300-series OpSpecs), contact the Air Transportation Division (AFS-200) at 202-267-8166.
(3) For additional information on 14 CFR parts 91 and 125 special authorizations (300-series OpSpecs/management specifications (MSpec)/letters of authorization (LOA)), contact the General Aviation and Commercial Division (AFS-800) at 202-267-8212.
Appendix 1 TABLE 1. CANADIAN-SPECIFIC SURVEILLANCE PHRASEOLOGY Existing “Radar” Phraseology New Generic “Surveillance” Phraseology
RADAR SERVICE TERMINATED (non-radar routing if required)
SURVEILLANCE SERVICE TERMINATED (non-surveillance routing if required)
RADAR SERVICE TERMINATED DUE TO (reason)
SURVEILLANCE SERVICE TERMINATED DUE TO (reason)
SECONDARY RADAR OUT OF SERVICE ADS-B SURVEILLANCE OUT OF SERVICE DUE TO (reason)
MODE CHARLIE NOT VALIDATED PRESSURE ALTITUDE NOT VALIDATED
MODE CHARLIE IS INVALID PRESSURE ALTITUDE IS INVALID
RADAR SERVICE TERMINATED SURVEILLANCE SERVICE TERMINATED
RESUME POSITION REPORTS RESUME POSITION REPORTS (aircraft IDENT) RADAR IDENTIFIED (position if required) (aircraft IDENT) IDENTIFIED (position if required) (aircraft IDENT) RADAR IDENTIFICATION LOST (aircraft IDENT) IDENTIFICATION LOST POINT OUT (position) (identification/Secondary Surveillance Radar (SSR) code) (track and altitude) (other information) POINT OUT (position) (identification/SSR code) (track and altitude) (other information) CONFIRM ADS-B ELIGIBLE? and if necessary—UNABLE TO ISSUE
CLEARANCE INTO ADS-B
EXCLUSIONARY AIRSPACE, MAINTAIN (altitude)
NEGATIVE ADS-B DUE TO EQUIPMENT
FAILURE
IF ABLE, CHANGE YOUR FLIGHT ID TO (FLIGHT ID) IF YOU READ, (appropriate instructions), then—(Action) OBSERVED, WILL
CONTINUE RADAR CONTROL IF YOU READ, (appropriate instructions), then—(Action) OBSERVED, WILL
CONTINUE SURVEILLANCE CONTROL (ACID) READING YOU ON 7700
CONFIRM THE NATURE OF YOUR
EMERGENCY
Appendix 1 Page 7 (and 8) TABLE 2. AUSTRALIAN-SPECIFIC SURVEILLANCE PHRASEOLOGY Existing “Radar” Phraseology New Generic “Surveillance” Phraseology
IDENTIFICATION TERMINATED (reason)
IDENTIFICATION TERMINATED (reason) PRIMARY RADAR OUT OF SERVICE ADS-B OUT OF SERVICE (reason) SECONDARY RADAR OUT OF SERVICE ADS-B OUT OF SERVICE (reason)
ADVISE TRANSPONDER CAPABILITY ADVISE ADS-B CAPABILITY
NEGATIVE TRANSPONDER NEGATIVE ADS-B
RE-ENTER MODE S AIRCRAFT
IDENTIFICATION
RE-ENTER ADS-B AIRCRAFT
IDENTIFICATION
SQUAWK IDENT TRANSMIT ADS-B IDENT
STOP SQUAWK STOP ADS-B TRANSMISSION
SQUAWK CHARLIE TRANSMIT ADS-B ALTITUDE
STOP SQUAWK CHARLIE WRONG
INDICATION
STOP ADS-B ALTITUDE TRANSMISSION (reason)
Appendix 2 APPENDIX 2. AUTOMATIC DEPENDENT SURVEILLANCE-BROADCAST (ADS-B)
IN-TRAIL PROCEDURE (ITP)
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 non-radar 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 allow ITP maneuvers to occur safely with reduced separation minima applied. IT will enable flightcrews to execute FL changes to improve ride comfort, avoid weather, or obtain more favorable winds to improve fuel economy and arrival
a. ITP Scenario. Figure 1, Reduction of Aircraft Separation Minima with In-Trail Procedure, illustrates a basic ITP scenario. The ITP aircraft (blue) wishes to climb from FL 340 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 1. REDUCTION OF AIRCRAFT SEPARATION MINIMA WITH IN-TRAIL
PROCEDURE ITP Aircraft Reference Aircraft (ADS-B Out required) Desired Altitude FL360 ADS-B not required
ALLOWED Procedural Separation FL350
- ITP Criteria - - ITP Criteria - FL340
3. ITP TERMINOLOGY.
a. Closing Groundspeed Differential. The difference between the ITP aircraft's groundspeed and a reference aircraft's groundspeed that results in a reduction of the ITP distance.
Appendix 2
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.
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 Figure 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 Procedures for Air Navigation Services - Air Traffic Management (PANS-ATM) DOC 4444, 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 which meet specified criteria and are referenced as part of an ITP clearance request to ATC.
Appendix 2 FIGURE 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, the closing Mach differential, as well as accuracy and integrity of the ADS-B data transmitted from participating aircraft. (See Table 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
Appendix 2 (fpm) during the maneuver. With these criteria, an ITP aircraft should never come closer than the 10 nautical mile (NM) separation minimum to a reference aircraft while passing through their altitude(s).
a. ITP Distance and Groundsp eed 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 closing ground speed differential, the distance between the aircraft should not become less than the ITP minimum separation of 10 NM.
c. Relative Altitude Criteria. The reference aircraft may not be more than 2,000 feet above or below the ITP aircraft.
d. 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 Figure 3, Similar Track).
e. 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).
f. 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 @ 1x10E 05.
• 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 knots) 95 percent.
Appendix 2 FIGURE 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 Communications (DCPC) is required; however, 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, and flightcrews must use free text messages as described in Table 2, Flightcrew Free Text Controller-Pilot Data Link Communication Message Set for In-Trail Procedure, and Table 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 to allow the controller to properly evaluate the request.
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 (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.
(3) Ensures both the ITP aircraft and reference aircraft are not maneuvering and not expected to maneuver during the ITP.
(a) 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 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 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 vertical speed. Upon completion of the maneuver, notify ATC of the ITP data loss.
g. 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 may request.
The reference aircraft both may be behind or ahead of the ITP aircraft or one may be ahead and
Appendix 2 one behind. Figure 4, In-Trail Procedure Climb/Descent Variations, depicts the approved ITP variations.
h. 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/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 International Civil Aviation Organization (ICAO) document PANS-ATM, DOC 4444, Section 15.2, Special Procedures for In-Flight Contingencies in Oceanic Airspace.
FIGURE 4. IN-TRAIL PROCEDURE CLIMB/DESCENT VARIATIONS
6. AUTHORIZATION TO CONDUCT ITP. Authorization from the FAA is required to conduct ITP. To receive authorization, operators should submit ITP proposals to their appropriate certificate management office (CMO), certificate-holding district office (CHDO), or Flight Standards District Office (FSDO) using the guidance contained in this section. ITP
Appendix 2 proposals must be evaluated and approved by the applicable FAA Flight Standards Service (AFS) policy divisions in Washington, DC, prior to authorization.
NOTE: Operators holding an active authorization for other ADS-B IN applications with specific requirements duplicated by those for ITP may reference such authorization requirements in their proposal as a means to demonstrate compliance with applicable ITP requirements.
a. Request for Authorization.
(1) Request for Authorization. U.S. operators seeking to conduct ITP must first contact their assigned FAA office to indicate their intent. When making an initial request, the operator should be prepared to provide the following:
(a) General information (aircraft, equipment, region of operation, etc.) about the proposed plan to conduct operations under the authorization; and
(b) The identification of the appropriate point(s) of contact (POC) for coordination during the FAA authorization process.
(2) At the time of the operator’s initial request, the FAA will provide the operator with information for obtaining relevant guidance and documents, as well as the proper content and format of the documentation required when submitting the formal request.
b. Required Documentation for Subm ission 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 unique aspects of their specific operation.
(2) Proposal Requirements. A separate proposal should be submitted for each aircraft type when making initial and subsequent requests for authorization to conduct ITP. Subsequent requests to add additional aircraft of the same make, model, and series (M/M/S) to an existing authorization should include the aircraft and equipment documentation required in paragraphs 4, 5, and 6 of this appendix.
(3) Letter of Request for Issuance of Authorization. The operator must submit a letter of request to the assigned PI requesting issuance of the authorization. The letter of request should include statements indicating the following:
(a) Proposed region(s) of operation;
(b) Type of aircraft M/M/S to be used;
(c) Description of ADS-B OUT/IN equipment to be used;