Flight Validation

Flight validation of instrument flight procedures has become an essential segment of flight inspection, as civil aviation is increasingly replacing the use of terrestrial NAVAIDS in favour of GNSS for en-route navigation (RNP) and, to a lesser degree for landing, where ILS will continue to be predominantly used.

Flight Validation of Fixed Wing Procedures, RNP

According to ICAO Document 9906/Vol 5 – Quality Manual for Instrument Procedure Design, publication of a new or modified approach or departure procedure requires a qualified flight validation as a prerequisite.

Common to all types of procedures is the desktop validation of the draft procedures, followed by a flight validation with respect to work load and flyability of the procedure with a King Air 350 of FCS. This entails a renewed validation of charts and checking of issued related to flight operations, e.g. suitability of published COM frequencies and a qualitative assessment of obstacles. Validation of the NAV database is an essential task in this process, where FCS checks the database’s contents compared to the AIP both in ARINC 424 and FMS formats employing a specialized validation tool. The validation flight is performed with a dedicated test (preproduction) database coded exclusively for FCS in the regular industry processing chain, as a safety precaution.

FCS validation of RNP procedures including LPV (APV SBAS) and GNSS or conventional navaids based RNAV, procedures is fully supported by the FCS aircraft’s flight management system (FMS) and tight integration of FIS and cockpit. Results are documented by flight validation and flight inspection reports, prerequisite for publication of the procedures in the AIP.
A process to validate new procedures was introduced in Germany already in 2001. The task is performed by flight validation pilots specially qualified and licensed for this purpose.

» Validating the NAV database

» LPV-200 precision approaches


Flight Validation of Helicopter Procedures

Flight Validation and flight inspection of helicopter IFR procedures represents a particular challenge. In order to solve the problem, FCS Flight Calibration Services GmbH entered into a special partnership with the Swiss air ambulance operator REGA. In July 2014, a special Agusta AW-109SP was equipped with a mobile flight inspection system of FCS. This platform is now being used for flight inspection and flight validation of the new LFN (Low Flight Network), as well as LPV procedures in Switzerland. In Germany, the first validation flight with the AW-109SP took place in 2016. A second AW109SP is being equipped for flight validation missions for redundancy purposes.

» Helifis Helicopter Flight Inspection FCS (Download 2,3 MB)


APV SBAS provides a wide area differential GPS (EGNOS) – based landing procedure with vertical guidance (LPV) and therefore a low decision altitude (DA) without the necessity for an ILS ground infrastructure. FCS services comprise check and flight validation of the procedure, supported both by cockpit avionics and flight inspection system for satellite performance evaluation, as well as a tool-based validation of the Navigation database including the FAS data block.

An extension of the EGNOS system enabled the introduction of The LPV-200 (SBAS CATI) procedures in 2016. These provide a decision height corresponding with a CAT I ILS. The first LPV-200 flight validation and flight inspection by FCS was performed at Vienna airport in April 2016.


DME/DME-based P-RNAV navigation is the designated GPS fallback procedure, with a precision of +- 1nm (RNAV1). Being a terrestrial Navaid, a flight check is mandatory. The FCS flight inspection system allows the simultaneous inspection of up to 4 DME or TACAN systems. Additionally, FCS SISMOS technology enables recording and analysis of up to 10 DMEs together with their associated propagation effects.

P-RNAV inspection uses the precise 3D antenna patterns of FCS King Air aircraft in real time, a prerequisite for complying with ICAO accuracy requirements with respect to absolute determination of field strength. Various projects carried out by FCS for EUROCONTROL have contributed to the improvement of the EUROCONTROL DEMETER DME simulation software.

EUROCONTROL’s P-RNAV related » guidelines may be found here.

Validation of NAV Databases

Commercial Aviation today is hardly conceivable without GPS navigation and the ICAO Performance Based Navigation (PBN) concept. The integrity of the flight management system (FMS) database is vitally important for GPS RNAV and precision approach procedures. The same applies to approach procedures with autopilot based barometric altitude guidance (AP BaroVNAV). For this reason, all new or modified approach and departure procedure data in German airspace are coded in a special “preproduction” database produced in the regular processing chain in line with ICAO recommendations.

These are subsequently flight validated and checked by means of the special FCS FIDIT Tool. FIDIT (Flight Inspection Database Integrity Tool) is based on the dbit® database tool employed by Lufthansa. FIDIT provides an automated comparison and validation of procedure data in ARINC 424 and FMS formats against applicable tolerances and reference data.Instead of a periodic flight inspection or flight validation of GPS based procedures, FCS carries out an annual database check to confirm that the procedure coding is still identical with published data.

FCS offers to support the validation e.g. of tailored or company routes NAV databases using our dedicated toolset. We are looking forward to your inquiry.