Calibration and Assessment of GPS based Approaches in Germany First Experiences and possible improvements of the regulatory requirements By Capt Thomas Wede Aerodata Flight Inspection GmbH
Introduction regulatory framework set by German MOT in 1998 ( NfL II-97/98) with effect of 08 Oct 1998 first GPS Standalone Procedures published by DFS (AIC 14/98) Calibration Guidelines published by Regulator DFS under Verfahrensanweisung GNSS-NPA Flugvermessung in 1999
Legal Framework 1 For this Type of Calibration the German MOT introduced a new Postholder: The Flight Inspector
Legal Framework 2 Flight Inspector GNSS-NPA: Responsible for Calibration Requires a Background in Calibration Business: Commercial Pilot License / IR or ATPL 2 years Experience as PIC 400 hrs as PIC GPS Qualification Training as Flight Inspector (4 weeks course, Final Exam, 5 Calibrations under Supervision)
GPS Standalone Procedures Braunschweig EDVE GPS26
Frankfurt EDDF Rwy 25L / 25R GPS Transition
NDB ( GPS Overlay) Schwäb. Hall EDTY NDB (GPS) 25
Mannheim EDFM SID (GPS) 28 SID ( GPS Overlay)
GPS Calibration Principles 1 Dilemma: GPS Calibration always a Spot Check GPS Calibration therefore focused on: * Data Integrity * Integrity of Data Processing * Procedure Design * Procedure Publication Process * Flyability * All Procedures flown with A/P and FMS
GPS Calibration Principles 2 Dilemma: Databases for FMS not available prior publication of new Procedures Reason: Legal and Liability Issues with Database Provider and Database Packer Provider (FMS Manufacturer) Solution so far: Procedure will be published; 1 Minute after Publication Date temporarily suspended by NOTAM until flight checked
GPS Calibration Procedures 1 Step 1: Excerpt from DFS Database
GPS Calibration Procedures 2 Step 2: Get relevant Pages from AIP Step 3: Crosscheck Coordinates AIP vs. DFS Database (4 Eyes- Principle)
GPS Calibration Procedures 3 Step 4: Get FMS Step 5: Crosscheck FMS Coordinates, Tracks and Distances vs. AIP & DFS Database
GPS Calibration Procedures 4 Step 6: Verify Chart vs. Textual Description AIP
GPS Calibration Procedures 5 Step 7: Verify all Aspects covered by crossreference to Checklist:
GPS Flight Check Principles Verify RAIM Status prior Takeoff All Procedures flown with A/P, FMS as Nav Source All Turns are Standard Rate Turns All Climbs with Minimum Climb Gradient, unless stated otherwise in Procedure Dilemma: For what Type of Aircraft do we calibrate? Single Engine A/C vs. 4-Engine Airliner Solution: Certain Speeds on Calibration as well as Procedures laid out above represent average A/C
GPS Calibration Procedures 6 Step 8: Analyse Calibration Logs & Print outs from FIS (WPDE, Lat.Dis.Err) Step 9: Write up Report (DFS Lotus Notes Database)
GPS Calibration Procedures 7
Results 1 In general, no severe Errors found on GPS Standalone Procedures in Germany Minor Errors found on Charts e.g. DME Distance vs. GPS Procedure Distance However, on Overlay Procedures (both NPA and SID), in part severe errors found in FMS Databases: * Shortcuts * Additional Waypoints in Procedure * Procedure only available for one Category of Aircraft (e.g. C/D)
Results 2 Further to FMS Database Problems: * Still no common Standard for Database Certification * Standards (ED76 / DO200a) developed; Date of Implementation not clear * until then, Operator is responsible for Integrity of Databases he uses! * This Approach is impracticable and a massive Obstacle to expand PRNAV Procedures!
Results 3 Some Approaches found to be challenging with regard to * Complexity of Procedure * Obstacle Situation * Airport Layout (Runway Length etc.) Training on GPS Procedures has to be expanded and promoted, especially within General Aviation Community
Results 4 Some Procedures found to be challenging with regard to * Complexity of Procedure * Length of Procedure * Initiating, Designing & Publishing of Procedure Who owns the Procedure??!
Conclusions GPS Calibration Procedures in Germany since 2001 New Postholder / License: Flight Inspector Calibration focussed on Procedure Verification and Verification of Data Integrity, rather than checking Signal in Space Procedures all found to be Flyable On NPA, Overlay and SID Procedures in Part massive FMS Database Problems Certification Standards for FMS Databases have to be introduced ASAP, else massive Safety Problems when expanding Use of PRNAV Procedures Training on GPS Procedures has to be promoted and expanded Open Issues of Ownership and cost of Procedures