PRE-FLIGHT VALIDATION RNAV GNSS APPROACH PROCEDURES FOR EPKT IN „ EGNOS APV MIELEC PROJECT ” Summary

The purpose of this document is to show evidence of the work carried out as part of the pre-flight flight validation activities of one RNAV approach Instrument Flight Procedures (IFP), down to LPV minima, at Katowice Airport (EPKT). The document is a deliverable of the TEN-T funded project “Support to the EGNOS APV Operational Implementation – APV MIELEC”.

In accordance with ICAO Assembly resolution 37-11 technological developments in aviation, especially in approaches and validations, will be determined by the need to implement navigation procedures based on characteristics (Performance Based Navigation -PBN) and GBAS system.Partial implementation approach procedures RNAV and RNP contained in Performance-Based Navigation (PBN) Manual is planned by 2016.EASA plans implementation of PBN Standard Instrument Departure (SID) / Standard Instrument Arrival (STAR) 2018.,And PBN approach procedures with vertical guidance (APV) (RNP APCH) to 2024.PBN means Area Navigation (RNAV) based on requirement for performance monitoring and alerting (Required Navigation Performance RNP) for aircraft operating along an air traffic service route, on an instrument approach procedure or in a designated airspace [4].For example, RNP 1 operations require the Lateral and Longitudinal Total System Error (TSE) to be within +/-1 nautical mile for at least 95% of flight time and on-board performance monitoring, alerting capability and high integrity navigation databases.With regard to RNP approaches (RNP APCH) the TSE shall be +/-0,3 nautical mile for at least 95% of flight time for the Final Approach Segment and on-board performance monitoring, alerting capability and high integrity navigation databases are required [3].

BACKGROUND ON RNAV APPROACHES
Area Navigation (RNAV) is defined as a method of navigation that permits aircraft operation on any desired course within the coverage of station-referenced navigation signals or within the limits of a self contained system capability, or a combination of these.RNAV was developed to provide more lateral freedom and thus more complete use of available airspace.This method of navigation does not require a track directly to or from any specific radio navigation aid, and has three principal applications: 1.A route structure can be organized between any given departure and arrival point to reduce flight distance and traffic separation; 2. Aircraft can be flown into terminal areas on varied pre-programmed arrival and departure paths to expedite traffic flow; 3. Instrument approaches can be developed and certified at certain airports, without local instrument landing aids at that airport.
Focusing on the last point, RNAV approaches can have several descent minima depending on the kind of RNAV approach to be flown:  RNAV (GNSS) NPA (Non Precision Approach): an approach without vertical guidance flown to the LNAV MDA/H (Lateral Navigation Minimum Descent Altitude/Height);  APV Baro (Approach with Barometric Vertical guidance): an approach with barometric vertical guidance flown to the LNAV/VNAV DA/H.APV Baro is a vertically guided approach that can be flown by modern aircraft with VNAV (Vertical Navigation) functionality using barometric inputs.Most Boeing and Airbus aircraft already have this capability meaning that a large part of the fleet is already equipped;  APV SBAS (Satellite Based Augmentation System): An approach with geometric vertical and lateral guidance flown to the LPV DA/H (Decision Altitude/Decision Height).APV SBAS is supported by satellite based augmentation systems such as WAAS (Wide Area Augmentation System) in the US and EGNOS (European Geostationary Navigation Overlay System) in Europe to provide lateral and vertical guidance.equivalent to an ILS localizer and the vertical guidance is provided against a geometrical path in space rather than a barometric altitude.
The 36th ICAO Assembly in 2007 passed a resolution encouraging States to implement approach procedures with vertical guidance (Baro-VNAV and/or SBAS) for all instrument runway ends, either as the primary approach or as a back-up for precision approaches by 2016.
The use of the European SBAS system -EGNOSpresents a feasible solution to APV approaches.
The use of the European SBAS system -EGNOSpresents a feasible solution to APV approaches:  Navigation system specifically designed for approach operations;  Europe coverage;  High accuracy and integrity;  Requires no infrastructure on the aerodromes themselves;  Supports autopilot coupling;  Standalone avionics possible thereby minimising retrofit costs.
The ESSP (European Satellite Service Provider) has officially declared the start of the EGNOS Safety-of-Life Service as of today, March 2nd 2011, following EC authorization to provide the service.
Intensive scientific and technological progress in aviation and flight approaches has been recognized in Poland.Polish Civil Aviation Authority are interested in the implementation of RNAV approaches in the short term into some of their airports.However, unlike to USA, France or Germany, in Poland, IFR navigation based on basic GNSS like GPS (Global Positioning System) is not currently accepted.The Polish Air Navigation Services Agency (PANSA) participates in this study by providing reports of the EGNOS SIS performance using a receiver installed on-ground.Royal Star Aero participates in the flight validation campaign directly by providing an aircraft.The pilots involved are IFR (Instrumental Flight Rules) licensed and are Royal Star Aero staff too.

PRE-FLIGHT VALIDATION RNAV GNSS APPROACH PROCEDURES
Research was conducted within the framework of the "Support to the EGNOS APV Operational Implementation -APV MIELEC" programme.Firstly, to the project were chosen two airports: Mielec Airport (EPML) as General Aviation airport and Katowice Airport (EPKT).During preparation to validation it turned out that EPML does not meet the requirements adopted in project and its infrastructure is unprepared to performing validation.That is why only EPKT was fully fledged participant at these project.Pre-flight validation was performed in line with ICAO Doc 9906 volume 5 "Validation of Instrument Flight Procedures", which provides guidance for conducting validation of instrument flight procedures, including safety, flyability and design accuracy [8].The reviewers involved realised that one of the obstacles (ID#79) was not well referenced.This entailed a substantial reduction of the LPV (Localizer Performance with Vertical guidance) minima value.The charts were corrected accordingly prior to the flight trials.
There is a slight deviation of the criteria concerning the position where the FPAP (Flight Path Alignment Point) has been located.In Katowice the ILS localizer (LOC) is located more than 305 meters from THR09.Thus the position of the FPAP should be the one specified in the following Fig. 4. The codification performed considered that the localizer was located at 305 m.Therefore the FPAP was coded in threshold 09 (THR09) position, being the length offset nil.However, it is not an important issue operationally speaking.The horizontal deviations that the pilot obtains are not exactly the same that the ones that would be obtained flying the existing ILS (Instrumental Landing System) procedure.Fig. 4 shows this small difference.

Fig. 5 .
Fig. 5. Difference between the Full Scale Deflection of the ILS with respect to the APV