Presentation on theme: "1 Zone A GNSS/EGNOS Trials ICAO AFI GNSS ITF 1 st MEETING Dakar, 17-18 th November 2003 ZONE A TRIALS Joint presentation by. Hughes Secrétan (ESA). Patrick."— Presentation transcript:
1 Zone A GNSS/EGNOS Trials ICAO AFI GNSS ITF 1 st MEETING Dakar, th November 2003 ZONE A TRIALS Joint presentation by. Hughes Secrétan (ESA). Patrick LEFEVRE (ASECNA)
2 Zone A GNSS/EGNOS Trials ICAO : GNSS AFI POLICY The ICAO Africa and Indian Ocean (AFI) Regional Implementation Plan includes a GNSS strategy Plan The Plan adopted by AFI States contains: –Phase 1( ): use of GPS implementation of an AFI GNSS test bed (extension of the EGNOS test bed) and preparation for the implementation of an operational system –Phase 2 ( ): operation of SBAS (EGNOS extension) for en-route to APV-I (Approach with Vertical Guidance) capabilities –Phase 3 (2012-…) : operation of SBAS with CAT-1 capabilities (Precision Approach), relying upon the availability of a civil satellite constellation (e.g. GALILEO)
3 Zone A GNSS/EGNOS Trials GNSS test-bed trials objectives To verify the navigation performances over selected areas and airports of western and Central Africa, To analyze ionospheric impacts, To evaluate critical issues (telecommunication network, expansion mode, airborne receivers performances,…) To validate the EGNOS simulation model outside Europe, To evaluate APV1 procedure design, constraints and operations To sensitize potential services providers and users, To develop expertise in the view of the implementation of the AFI test bed and an operational system
4 Zone A GNSS/EGNOS Trials Implementation of a Test Bed in Central Africa (zone A), in line with the ICAO Strategy (Phase I) from December 2002 to september Project with no exchange of funds Links between the RIMS and ESTB based upon AFISNET satellite communication network 4 RIMS installed by ASECNA at NDjamena, Lomé, Douala and Brazzaville AFI Test Bed implementation in Zone A NDjamena Douala Brazzaville Lomé VPL Simulation ( ESA source)
5 Zone A GNSS/EGNOS Trials ZONE A PROJECT PARTNERS –ESA (European Space Agency) : provided one ECUREV RIMS and CPF modification to manage the Dakar RIMS, –ASECNA : provided facilities for the RIMS, its EGNOS equipped calibration aircraft, APV1 design procedure –French DGAC : provided the airborne navigation software and data analysis support, –Eurocontrol : supplied the PEGASUS software for data acquisition and processing, –ENAV, the Italian Space Agency loaned 3 RIMS to ASECNA through ESA. –NAMA (Nigerian Airspace Management Agency), which provided data for APV1 procedures design, support for the flights and organized demonstrations in Lagos, Kano and Port- Harcourt,
6 Zone A GNSS/EGNOS Trials Zone A GNSS test bed architecture Douala : RIMS and VSAT Brazzaville : RIMS and VSAT VSAT ASECNA AFISNET INMARSAT GPS INTELSAT Thales Router Ranging +GES CPU Thales Router Honefoss ESTB CPF CPU Lomé :Rims and VSAT NDjaména RIMS and VSAT TOULOUSE HONEFOSS (NORVEGE) RIMS data to CPF GPS signals EGNOS navigation Message (integrity and corrections
7 Zone A GNSS/EGNOS Trials IMPLEMENTATION ISSUES RIMS Antenna location Interferences issues Connexions to communication network No spares Lack of documentation No central monitoring No FTP server Not an operational system Management
8 Zone A GNSS/EGNOS Trials RIMS layout GPS/GEO antenna (Novatel) RIMS Receiver Core Computer Atomic Clock Local Maintenance Equipment RIMS DATA SYNC DATA DAT IP Router NETWORK Screen 15 Power Supply PC Processor Unit GPS/GEO Novatel OEM3 L1/L2 Receiver DAT Recording Unit Rubidim Atomic Clock Keyboard IP Router
9 Zone A GNSS/EGNOS Trials GNSS expected performances: vertical accuracy
10 Zone A GNSS/EGNOS Trials GNSS expected performances : VPL Availability
11 Zone A GNSS/EGNOS Trials ATR42 Avionics layout GPS/Glonass Antenna GPS/Glonass Antenna RTK Receiver Calibration computer TBUE Receiver Novatel Receiver Guidance computer * Data collection computer Flight Management System (FMS) Tracking data (to Pegasu s) EGNOS data (to Pegasus ) GPS Antenna Honeywell Receiver Navigation sensors Cockpit Electronic Displays EGNOS EFIS EGNOS guidance sub-system EGNOS raw data collection sub-system Airborne Calibration sub-system Aircraft Navigation System Existing equipment in the ATR42 equipment provided by ESA New equipment acquired and installed by ASECNA
12 Zone A GNSS/EGNOS Trials ATR42 GNSS Avionic layout (pictures) EGNOS cockpit guidance display (EHSI) ADAGIO cabin display
13 Zone A GNSS/EGNOS Trials Final Approach procedures Runway Accuracy Alarm Limit Horizontal Vertical Horizontal Vertical CAT I APV2 APV1 NPA 16 m 4 à 6 m 8 m 40 m 10 à 15 m20 m 16 m220 m 20 m Not applicable 40 m 50 m DH/MDH (mini) Horiz. Visi. (mini) Protection areas Slope 200 ft 250 ft 550 m T.B.D 1200 m reduced (ILS) near ILS near ILS Important => Mimima if obstacles 5.2% (3°) Descent + stabilization => CFIT risk APPROCH CATEGORIES Vertical 5.2%(3°) 200 ft 1000 m T.B.D 1800 m With Land. lights Without Land. lights Integrity/continuity of service yes not Slope 5.2% (3°) Horizontal plane MDH ( 250 ft) 220 m 16 m 20m 16 m 8 m MAPT 250 ft 200 ft
14 Zone A GNSS/EGNOS Trials DOUALA RWY 30 APV1 Instrument Approach Chart
15 Zone A GNSS/EGNOS Trials APV1 benefits (1) Control of the vertical position thanks to the EGNOS signal and added descent fixes No more flat step before the miss approach point (see point V) reducing CFIT (Controlled Flight Into Terrain) risk Reduced operational minima Ease of flyability
16 Zone A GNSS/EGNOS Trials APV1 benefits (2)
17 Zone A GNSS/EGNOS Trials GNSS ESTB Horizontal Guidance Dakar ILS Localizer error ( A) against distance to threshold (NM) ILS Cat I Template ESTB Lateral angular error ( A) Guidance signals provided by ESTB navigation system are similar to actual ILS deviations.
18 Zone A GNSS/EGNOS Trials GNSS/ESTB Vertical Guidance Dakar ILS Glide error ( A) against distance to threshold (NM) and ILS Cat I Template ESTB Vertical angular error ( A) Conversion of the constant linear Vertical ESTB error into angular Error (blue line) Impact of trajectography Path model (red line) Vertical guidance signals provided by ESTB are close to ILS Glide deviations and available on all Runways
19 Zone A GNSS/EGNOS Trials Zone A preliminary results : accuracy (1) Horizontal error (HPE)Vertical error (VPE)DateGEOPeriodMean95%Mean95%16/09/03120Day /09/03120Night /09/03120Day /09/03120Night /09/03120Day /09/03120Night /09/03131Day /09/03131Day /09/03131Day /09/03131Day
20 Zone A GNSS/EGNOS Trials Zone A preliminary results : accuracy (2) Accuracy performance, when full corrections are broadcast, is complying with the APV1 SARPS requirements with HPE around 3m (95%) and VPE around 4.5 m (95%)
21 Zone A GNSS/EGNOS Trials Zone A preliminary results : availability (1) DatePRNPeriod Full corrections Hor. APV1Vert. APV1 16/09/03120Day 77.34%75.64%75.82% 16/09/03120Night 85.99%84.60%83.81% 18/09/03120Day 93.96% 92.14% 91.41% 18/09/03120Night 96.16% 94.93% 93.95% 22/09/03120Day 92.11%88.71%89.07% 22/09/03120Night 94.90% 93.23% 92.56% 17/09/03131Day 95.47%93.85%91.91% 17/09/03131Night 99.05%97.97%98.66% 19/09/03131Day 98.52% 97.37% 96.91% 20/09/03131Night 100%
22 Zone A GNSS/EGNOS Trials Zone A preliminary results : availability (2) Note : results obtained with the FAA tool : SISAT
23 Zone A GNSS/EGNOS Trials Zone A preliminary results : availability (3) Numerous causes of unavailability : –Telecommunications outages or malfunctions, (NDjaména, Brazzaville, Toulouse), –interferences issues (NDjaména and Douala ?), –RIMS mains failure (NDjaména), –RIMS malfunctions –destruction of GNSS antenna at Douala from lightning, –Erroneous RIMS re-configurations after re-starts (Brazzaville, NDjaména and Douala), –Ionospheric effects –RIMS HMI ( human machine Interface ) miss designed for local maintenance purpose
24 Zone A GNSS/EGNOS Trials Zone A preliminary results : availability (4) When the ESTB signal is providing full corrections (fast corrections + iono corrections), the HPL/VPL availability for APV1 is roughly 98.5% (between 97% and 100%). APV1 service availability is better during night then day, most probably due to ionosphere effects, in particular the GIVE that is smaller during night. The improvement of the quality of the RIMS and communications lines, which are generating some gaps and time-delay may improve significantly the ESTB performances
25 Zone A GNSS/EGNOS Trials Zone A preliminary results : availability (5) The service availability on AFI-A area is mainly affected by 2 phenomena: – Dont use IGPs events (GIVE set to dont use). Such GIVE status may be explained by a high ionosphere activity. More static tests would be very useful to monitor the ESTB iono corrections, understand and optimize the CPF configuration regarding such iono activity. A dedicated iono receiver is under installation at Douala, – UDRE set to not monitored by the CPF. Most of the satellites located in the South part of the region have an UDREI of 14 (not monitored) and are therefore not used in the navigation solution. It needs to be investigated in more details as it prevents quite a significant amount of satellites from being used.
26 Zone A GNSS/EGNOS Trials ZoneA preliminary results: S.I.S (Hor.) Integrity (1)
27 Zone A GNSS/EGNOS Trials ZoneA preliminary results: S.I.S (vert.) Integrity (2)
28 Zone A GNSS/EGNOS Trials ZoneA preliminary results : integrity (3) As shown in the previous diagrams, no misleading information (non integrity events) happened during all the static tests.
29 Zone A GNSS/EGNOS Trials Flight tests and demonstrations (1) Extensive flight tests and demonstrations were performed in; –Lomé (Togo) –Lagos, Kano and Port-Harcourt (Nigeria) –Malabo (Equatorial Guinea) –Libreville (Gabon) –Douala and Yaoundé (Cameroon) More than 100 persons including pilots, African Civil Aviation Authorities and Air Forces representatives flew aboard the ATR42. GNSS presentations were carried at every airport (except Malabo).
30 Zone A GNSS/EGNOS Trials Flight tests and demonstrations (2) All the FAS data (Final Approach Segment) prepared for the APV1 procedures were right On all the flown approaches, the runway axis alignments were well within the CAT1 tolerances (and APV1). Regarding the descent path it was found on two airports a difference of about 50 ft at the threshold. Investigations are on-going to determine the cause.
31 Zone A GNSS/EGNOS Trials RIMS installation recommendations Training of technical staff is necessary to handle maintenance operations Site survey in compulsory in order to minimise installation delays ( interference effects, length of cable between antenna and Rims, etc…) RIMS alimentation must be on unbreakable power supply Connection to ground network ( réseau de terre) must be necessary done with appropriate cable Access to telecommunications network must be done either by V24 link or by IP link using frame relay multipliers equipments.
32 Zone A GNSS/EGNOS Trials Conclusions Preliminary results show EGNOS may satisfy AFI navigation requirements contained in the GNSS AFI Strategy, Hardware, software and operation procedures constituting the test-bed have to be improved to significantly increase the ESTB performances, Training and expertise of AFI staff about GNSS evaluation is mandatory, Complementary evaluations have to be made in equatorial region ( either by extension of zone A trials or through extensive zone C evaluation).
33 Zone A GNSS/EGNOS Trials THANK YOU FOR YOUR ATTENTION