B. RABILLER DGAC/DCS Gatwick 12-13 February 08

1. Progress report on the development of the navigation AMC 20 materials including the use of the VNAV capabilities B. RABILLER DGAC/DCS Gatwick 12-13 February 08 CNS/ATM Steering Group 40th meeting

2. Introduction • RNP APCH (Without APV Baro VNAV criteria) • AMC 20-XX Draft 2.8 submitted to EASA beginning of January 08 for NPA publication • RNP APCH (With APV Baro VNAV criteria) • Based on AMC 20-XX Draft 2.8 • Includes APV Baro VNAV airworthiness and OPS criteria (“AIRWORTHINESS APPROVAL AND OPERATIONAL CRITERIA FOR RNP APPROACH (RNP APCH) OPERATIONS INCLUDING APV BARO VNAV OPERATION” ) • AMC 20-APV Baro VNAV Draft 1.2 issued • Comments are welcomed • LPV • AMC 20-LPV Draft 1.2 issued. • Comments are welcomed

3. AMC 20-XX Draft 2.8RNP APCH (Without APV Baro VNAV criteria) • In concluding AMC 20-XX Step 1 activity, the editorial group managing this task (EASA Task 20.003) have: • Made a complete editorial review of the AMC (terminology, consistency, format, …) • Updated the document to bring it in-line with the equivalent material in the ICAO Performance Based Navigation (PBN) Manual published earlier last year. • Included latest text for Navigation Database Integrity consistent with that recently agreed for inclusion in EU-OPS (equivalent provisions to the new EU-OPS 1.873 and its ACJ).

4. AMC 20-XX Draft 2.8RNP APCH (Without APV Baro VNAV criteria) • The editorial group managing this task have also: • Included an Annex D showing the applicability of the various AMC documents relative to RNAV Approach Operations. • Annex D is brand new. • Annex D explains which equipment qualification was tied to which AMC and therefore which approval. • As a summary no technical amendment from the AMC 20-XX Draft 2.7 presented during the last CNS/ATM meeting

5. AMC 20-APV Baro VNAV Draft 1.2

6. AMC 20-APV Baro VNAV Draft 1.2RNP APCH with APV Baro VNAV operation • An update of the AMC 20-XX draft 2.8 to include APV Baro VNAV airworthiness and operational criteria. This update is also called AMC 20-XX step 2 • AMC 20-XX (step 2) is now applicable to RNP APCH with and without APV Baro VNAV i.e. lateral only and lateral/vertical • For airworthiness criteria: lateral and vertical requirements are clearly separated in the document in order to ease approval of systems w/o vertical capability • E.g. lateral accuracy requirement is separated from the vertical one; dedicated table for the lateral and vertical required functions;…. • For operational criteria and for clarity reason, ops procedures include lateral and vertical aspects in the same paragraph (e.g. pre-flight planning, prior to commencing the procedure, during the procedure,…) • 6.3 Accuracy • 6.3.1 Horizontal • The Lateral and Longitudinal Total System Error (TSE) of the on-board navigation system must be equal to or better than: ……. • 6.3.2 Vertical . • a) VNAV navigation accuracy • For the Final approach segment, the error of the airborne ….. 10.1.3 During the Procedure The final approach trajectory must be intercepted no later than the FAF in order for the aircraft to be correctly established on the final approach course before starting the descent (to ensure terrain and obstacle clearance). ………. For APV Baro-VNAV operation, the crew should check that the two altimeters provide equivalent altitude (difference of 100 feet max) at or before FAF …… ……….

7. AMC 20-APV Baro VNAV Draft 1.2RNP APCH with APV Baro VNAV operation • At least two points to be discussed and clarified: Point 1: Vertical total system error should be consistent with the procedure design criteria • Vertical TSE requirement (excluding ASE) is 224 ft at 3 Sigma • Obstacle clearance criteria from PANS OPS is based on an OCH of 246 ft (75 m). • There is no apparent safety margin • Reduction of FTE budget is a way to address this inconsistency (e.g. FTE Reduction from 200 ft to 150 ft) PANS OPS AMC 6.3.2.c) Vertical Total System Error (excluding altimetry) In any case for the final approach segment, the vertical Total System Error (excluding altimetry) should be less than 224 ft on a 99.7 percent probability basis when the aircraft is descending at or below 5000 ft. 4.4.1 Minimum obstacle clearance (MOC) a) The MOC in the final approach (MOCapp) is 75 m.

8. AMC 20-APV Baro VNAV Draft 1.2RNP APCH with APV Baro VNAV operation Point 2: VNAV transition (vertical fly by) requirement in particular for the FAP: • Should it be a required or a recommended function? • How should it be implemented? Extract from draft AMC: “Vertical Fly-by transition assessment should be evaluated in manual and in autopilot mode. It is recalled that momentary deviation below the published minimum procedure altitude at the FAP is acceptable provided the deviation is limited to no more than 50 feet.” FAP

9. AMC 20-LPV Draft 1.2

10. AMC 20-LPV Draft 1.2LPV operation • This AMC is addressing only the LPV approach which is the Final Approach Segment (FAS). • Operation on other segments (initial/intermediate; transition,…) are addressed through: • the appropriate AMC: for RNP APCH the AMC 20-XX ; for PRNAV the TGL10/AMC 20-16). • ATC operational procedure using vectoring (e.g Use of the VTF function onboard) Continuation of a RNP APCH PRNAV transition Vectoring FAS FAS FAS

11. AMC 20-LPV Draft 1.2LPV Equipment and installation • GNSS SBAS stand-alone equipment approved in accordance with • E/TSO C146a class Gamma 3 • Aircraft installation compliant with requirements of AMC section 6 to 9 • Integrated navigation system (e.g. FMS) incorporating a GNSS SBAS sensor. • E/TSO‑C115b and AC 20-130A are acceptable means of compliance for the approval of the navigation system when augmented by the: • Functional requirements of E/TSO-C146a class Gamma 3. • The GNSS SBAS sensor is approved in accordance with E/TSO C145a class Beta 3. • The aircraft installation complies with requirements of AMC section 6 to 9. • For an approach system incorporating a class Delta GNSS SBAS equipment. • System is approved in accordance with E/TSO‑C146a Class Delta 4 • Aircraft installation compliant with requirements of AMC section 6 to 9.

12. AMC 20-LPV Draft 1.2LPV open points • ETSO aspect. • ETSO C 145a and C146a are still not issued (NPA process ongoing). • Reference to DO 229C is essential. • It should be noted that FAA already issued TSO C145b and C 146b based on DO 229D. • Distance indicated for a LPV approach • Is it always the distance to the LTP/FTP whatever the case? • In particular if LTP/FTP not collocated with MAPt • Is distance to the MAPt could be indicated in some cases? • DO 229 clearly indicates that distance to the LTP/FTP must be indicated but discussion with navigation data base coder is not so conclusive. LTP/FTP dist to LTP/FTP MAPt dist to MAPt

13. Summary

14. APPLICABILITY OF AMC DOCUMENTS TO RNAV APPROACH OPERATIONS

15. P-RNAV Initial & Intermediate Approach Segments RNP APCH Initial & Intermediate Approach Segments LNAV Final Approach Segment LNAV/VNAV Final Approach Segment LPV Final Approach Segment * ** E/TSO C129 (class B1, B3, C1 or C3) + FMS E/TSO C129 (class A1) ** ** E/TSO C145a (class Beta 1) + FMS * ** E/TSO C145a (class Beta 2) + FMS * ** E/TSO C145a (class Beta 3) + FMS * E/TSO C146a (class Gamma 1) ** ** E/TSO C146a (class Gamma 2) ** E/TSO C146a (class Gamma 3) E/TSO C146a (class Delta 4) ** ** ** ** Applicable Airworthiness and Operational Approval criteria: (*) operation possible if a Baro-VNAV function is supported by the navigation equipment AMC 20-16 AMC 20 LPV (**) operation not possible Future development for SBAS equipment AMC 20 RNP APCH

16. P-RNAV Initial & Intermediate Approach Segments RNP APCH Initial & Intermediate Approach Segments LNAV Final Approach Segment LNAV/VNAV Final Approach Segment LPV Final Approach Segment * ** E/TSO C129 (class B1, B3, C1 or C3) + FMS RNP/APCH  Use of AMC 20-XX (LNAV) E/TSO C129 (class A1) ** ** E/TSO C145a (class Beta 1) + FMS * ** PRNAV  Use of AMC 20-16 E/TSO C145a (class Beta 2) + FMS * ** LPV  Use of AMC 20-LPV E/TSO C145a (class Beta 3) + FMS * E/TSO C146a (class Gamma 1) ** ** E/TSO C146a (class Gamma 2) ** E/TSO C146a (class Gamma 3) E/TSO C146a (class Delta 4) ** ** ** ** No LNAV/VNAV approval criteria so far for this equipment Applicable Airworthiness and Operational Approval criteria: (*) operation possible if a Baro-VNAV function is supported by the navigation equipment AMC 20-16 AMC 20 LPV (**) operation not possible Future development for SBAS equipment AMC 20 RNP APCH

17. AMC 20-XZ, RNP AR Operations

18. Status • Final Draft delivered to EASA Rulemaking Directorate in September 2007 • Draft AMC did not reflect a consensus of the drafting group (20.003) • Meetings had already been extended to try to resolve differences between European and US industry • Rulemaking “called time” on the group

19. Status • Plan was to publish draft AMC as was • Solicit comments through the NPA process • Try and resolve issues during the comment response phase • Letter of complaint to EASA from European industry

20. EASA Standards for RNP AR Certification • AMC deemed to be contrary to CRI applied to manufacturer’s product • Issue concerning navigation system performance under degraded conditions e.g., Probable, Remote and Extremely Remote Failures • Such evaluations can have a bearing on the eventually approved RNP value i.e., sizing cases • Letter called for resolution of these issues prior to EASA public consultation

21. EASA Standards for RNP AR Certification • In defence of the existing draft • RNP AR has both benign and demanding instrument procedure characteristics • The most demanding procedures indeed require full evaluation of normal and abnormal operating conditions to dimension acceptable lateral deviation limits • Less demanding procedures can rely more on traditional processes • The draft does not try to prescribe a single method • It does address certain failure considerations under FTE assessment

22. The Dilemma • The European manufacturer CRI is for the most demanding of RNP AR applications • Manufacturer also claims that issue is one of integrity as per the CRI, and not navigation performance • FAA AC 90-101 does not not address synthesis of failures in this way • Part of operations evaluation

23. EASA Response • Meeting planned between certification and rulemaking specialists in the second half of February • An accommodation to be found • Plan is still to release NPA for public consultation by the end of March

24. Flight Operations Safety Assessment (FOSA) • FOSA is the assessment of the overall operational safety of an RNP AR procedure • The glue between the aircraft SSA, the procedure design criteria and the flight operations procedures and training • Today, no guidance exists as to how a FOSA should be conducted

25. Existing Material • Draft AMC 20-XZ • Requires the manufacturer to develop operational support documentation detailing: • Acceptable configurations • Recommended FCOM material for failures • Analyses performance e.g., RF performance for given radius and TAS • Flight crew training • Conduct of the instrument procedure • FOSA guideline included in Annex E • ICAO RNP AR Manual • Instrument procedure design criteria based on FAA Order 8260.52

26. ICAO IFPP • The Performance Based Navigation (PBN) Working Group of the IFPP investigating FOSA methodology • EUROCONTROL taking the lead and has commissioned a research project involving European carriers, aircraft manufacturers, State Authorities and safety assessment consultants

27. EUROCONTROL FOSA Project • Data search • Two pilot studies under consideration • Bastia, Corsica with Air France A320 • Norwegian airfield with SAS B737NG • Objective is to produce guidance material including checklist, that can be applied to any AR application • Ensure a consistent approach to implementing RNP AR • Provide safety assurance against ICAO guidance material

28. Summary

29. RNP AR Operations • AMC 20-XZ still requires some refinements to satisfy European industry • Putting FOSA in place with ICAO published guidance seen as essential to moving AR into more public procedures and assuring safety of operations