Appendix 2 NOTE: Operators/pilots should contact manufacturers to discern if any annunciation of inertial coasting is suppressed following loss of radio updating.
(2) Must be able to accept a position update immediately prior to takeoff.
(3) Must exclude VORs greater than 40 NM from the aircraft.
f. Minimum Performance Standard for each Route or Procedure. The total system error must be less than or equal to 1.0 NM (95%) throughout the route. In order to maximize the amount of IRU coasting allowed, the flight technical error for D/D/I aircraft on terminal procedures should be limited to 0.5 NM (95%).
NOTE: The FAA assures that systems meeting the D/D/I RNAV minimum performance standard satisfy this requirement on all identified routes and procedures, and these RNAV systems do not require further evaluation. Systems seeking approval using different RNAV system characteristics or performance must demonstrate this performance for each published route or procedure.
Appendix 3
Page 1 APPENDIX 3. NAVIGATION DISPLAYS AND FUNCTIONS
1. Navigation data, including a to/from indication and a failure indicator, must be displayed on a lateral deviation display such as CDI, (E)HSI and/or a navigation map display.
These shall be used as primary flight instruments for the navigation of the aircraft, for maneuver anticipation and for failure/status/integrity indication. They shall meet the following requirements:
a. Non-numeric lateral deviation display (for example, CDI, (E)HSI), with a To/From indication and a failure annunciation, for use as primary flight instruments for navigation of the aircraft, for maneuver anticipation, and for failure/status/integrity indication, with the following five attributes:
(1) The displays shall be visible to the pilot and located in the primary field of view (± 15 degrees from pilot’s normal line of sight) when looking forward along the flight path.
(2) The lateral deviation scaling should agree with any alerting and annunciation limits, if implemented.
(3) The lateral deviation display must also have a full-scale deflection suitable for the current phase of flight and must be based on the required total system accuracy.
(4) The display scaling may be set automatically by default logic or set to a value obtained from a navigation database. The full-scale deflection value must be known or must be available for display to the pilot commensurate with en route or terminal values.
(5) The lateral deviation display must be automatically slaved to the RNAV computed path. The course selector to the deviation display should be automatically slewed to the RNAV computed path or the pilot must adjust the OBS or HSI selected course to the computed desired track.
NOTE: The normal function of stand-alone GNSS equipment meets this requirement.
b. If using a navigation map display, it should give equivalent functionality to a lateral deviation display as described above, (Appendix 3, paragraph 1.a. (1-5)), readily visible to the pilot, with appropriate map scales (scaling may be set manually by the pilot).
2. The following system functions are required as a minimum within RNAV equipment:
a. The capability to continuously display to the pilot flying, on the primary flight instruments for navigation of the aircraft (primary navigation display), the RNAV computed desired path and aircraft position relative to the path.
b. For operations where the required flight crew is two pilots, means for both pilots to verify the desired path and the aircraft position relative to the path.
Appendix 3
c. A navigation database, containing current navigation data officially promulgated for civil aviation, which can be updated in accordance with the Aeronautical Information Regulation and Control (AIRAC) cycle and from which terminal airspace procedures can be retrieved and loaded into the RNAV system. The stored resolution of the data must be sufficient to achieve the required total system error. The database must be protected against pilot modification of the stored data.
d. The means to display the validity period of the navigation data to the pilot.
3. The means to retrieve and display data stored in the navigation database relating to individual waypoints and navigation aids, to enable the pilot to verify the route/procedure to be flown.
4. The entire RNAV segment of the DP or STAR to be flown must be extracted from the navigation database. In this document, the RNAV segment begins at the first occurrence of a named waypoint, track, or course and ends at the last occurrence of a named waypoint, track, or course. Heading legs, prior to the first named waypoint or after the last named waypoint of a procedure, are not part of the RNAV segment and do not have to be loaded from the database.
Similarly, direct-to-fix legs prior to the first named waypoint of a procedure are not part of the RNAV segment. While not required, the ability to extract the entire RNAV procedure, including heading and direct-to-fix legs, from the database is a recommended function.
5. The means to display the following items, either in the pilot’s primary field of view, or on a readily accessible page on a multi-function control display unit (MCDU).
a. The active navigation sensor type
b. The identification of the active (To) waypoint
c. The ground speed or time to the active (To) waypoint
d. The distance and bearing to the active (To) waypoint
6. Where the MCDU is used to support accuracy checks by the pilot, the capability of displaying lateral deviation with a resolution of at least 0.1 NM.
7. The capability for the navigation system to execute a “Direct to” function.
8. The capability for automatic leg sequencing with display of sequencing to the pilot.
9. The capability to execute procedures extracted from the onboard database including the capability to execute fly-over and fly-by turns.
10. The capability to execute leg transitions and maintain tracks consistent with the following ARINC 424 path terminators:
Appendix 3
a. The aircraft must have the capability to automatically execute leg transitions and maintain tracks consistent with the following ARINC 424 path terminators, or their equivalent:
• Initial Fix (IF)
• Course to Fix (CF)
• Direct to Fix (DF)
• Track to Fix (TF)
NOTE 1: Path terminators are defined in ARINC Specification 424, and their application is described in more detail in RTCA documents DO-236B and DO-201A.
NOTE 2: Numeric values for courses and tracks must be automatically loaded from the RNAV system database. However, automatic CF capability is not required for approval to fly: (1) all RNAV routes covered by this AC as these are constructed using TF path terminators, or (2) those ODPs using a DF or TF path terminator for the first segment.
b. The aircraft must have the capability to automatically execute leg transitions consistent with VA, VM and VI ARINC 424 path terminators, or must be able to be manually flown on a heading to intercept a course or to go direct to another fix after reaching a procedure-specified altitude.
c. The aircraft must have the capability to automatically execute leg transitions consistent with CA and FM ARINC 424 path terminators or the RNAV system must permit the pilot to readily designate a waypoint and select a desired course to or from a designated waypoint.
11. The capability to load a named RNAV route into an RNAV system from the database is a recommended function. However, if all or part of the RNAV route (not DP or STAR) is entered through the manual entry of fixes from the navigation database, a TF leg type must be used to define the path between a manually entered by name fix and the preceding and following fixes.
12. The capability to display an indication of the RNAV system failure, including the associated sensors, in the pilot’s primary field of view.
13. For multi-sensor systems, capability for automatic reversion to an alternate RNAV sensor if the primary RNAV sensor fails.
NOTE: This does not preclude providing a means for manual navigation source selection.
14. Database Integrity. The navigation database should be obtained from a database supplier holding an FAA Letter of Acceptance (LOA) in accordance with AC 20-153. This LOA provides recognition of a data supplier’s compliance with the data quality, integrity and quality management practices of RTCA DO-200A, Standards for Processing Aeronautical Data. The
Appendix 3 operator’s supplier (e.g., FMS manufacturer) must have a Type 2 LOA. Discrepancies that invalidate a procedure must be reported to the database supplier and affected procedures must be prohibited by an operator’s notice to its flight crew. Aircraft operators should consider the need to conduct ongoing checks of the operational navigation databases in order to meet existing quality system requirements.
NOTE: AC 20-153 contains procedures for database LOAs.
15. It is recommended RNAV systems provide lateral guidance so aircraft remain within the lateral boundaries of the fly-by transition area as defined in DO-236B, section 3.2.5.4.1.