UK RNAV (GNSS) INSTRUMENT APPROACH PROCEDURES
1 Introduction
1.1 The CAA has approved the use in the UK of RNAV (GNSS) Approach procedures. RNAV (GNSS) 2-Dimensional Non-Precision Approach (NPA) procedures and 3-Dimensional Barometric VNAV (APV Baro VNAV) approach procedures will be authorised only to suitable instrument runways, at appropriately equipped licensed aerodromes with Air Traffic Control (ATC) services.
2 General
2.1 Notified RNAV (GNSS) approach procedures will be available for use by all Instrument and IMC Rated pilots of UK and foreign registered aircraft. Aircraft must have suitably approved equipment.
2.2 UK AOC holder's approval to fly these approaches will be administered under current CAA oversight arrangements.
2.3 CAP 773, Flying RNAV (GNSS) Approaches in General Aviation Aircraft, due for publication in August 2007 will provide guidance to pilots and instructors in the use of GPS for approach operations. The CAP contains some technical information on the function of GPS together with equipment requirements, human factors considerations, training and practical guidance for the use of GPS during RNAV (GNSS) approach operations.
2.4 CAA Safety Sense Leaflet No.25 (Use of GPS) has been updated to include safety related guidance and information on the use of GPS in IMC and on instrument approaches.
3 Aircraft Navigation System
3.1 The aircraft navigation system shall include at least one GPS receiver. The navigation system must be approved to conduct:
(a) RNAV (GNSS) stand-alone approaches1; or,
(b) Approaches of RNP 0.3 or RNP-RNAV0.3 type2.
3.2 All approved installations must have the appropriate approval for RNAV (GNSS) approach operations entered in the Aircraft Flight Manual (AFM), Pilot Operating Handbook (POH) or equivalent.
The navigation system can be as a minimum:
(a) A system only based on GNSS having at least one GPS receiver qualified to TSO-C129a / ETSO-C129a Class A1 or
TSO-C146()3 / ETSO-C146() Class Gamma and operational class 1, 2 or 3; or,
(b) Amulti-sensor system (eg, Flight Management System) having at least one GPS receiver qualified to TSO-C129() / ETSO- C129() Class B1, C1, B3 or C3 or TSO-C145() / ETSO-C145() class 1, 2 or 3 (with equivalent integration guidance).
3.3 Any operating limitations mentioned in the AFM, concerning use of the navigation system on RNAV (GNSS) approach procedures must be observed.
3.4 Pilots must be able to determine that the on-board aeronautical database and software version in use for the navigation system is valid for the time of flight. The entire approach procedure must be loadable, by name, from the navigation database.
Manually entered and overlay procedures must not be used as the primary reference on any approach, at any time.
1Designations may include RNAV/GNSS approach, RNAV/GPS approach, stand-alone GPS approach or GPS Non-Precision Approach (NPA).
2 The terminology used in Aircraft Flight Manuals may vary between aircraft types.
3 () refers to any version of the Equipment Technical Standard Order is acceptable eg, TSO-C129 or TSO-C129a.
4 Pilot Training and Licensing
4.1 Training requirements in the use of RNAV (GNSS) approaches will now be added to the IMC and IR rating syllabi. These changes will be published by AIC and notified directly to heads of training by the CAA Chief Flight Examiner (CFE). Further information will be available by press release and via industry representative bodies. Guidance for instructors, Flight Training Organisations (FTOs) and Registered Facilities on the training requirements and technical information for pilots will be made available on the CAA website in the form of CAP 773. This will ensure that new pilots are appropriately trained in GNSS approach operations. Flight Training and Testing Policy is available at:
http://www.caa.co.uk/pld
4.2 Existing IMC Rating and IR holders are formally advised to undergo additional training to the satisfaction of an instructor holding a recognised, current instructor qualification who is qualified to teach for the Instrument or IMC Rating, in accordance with LASORS and either JAR FCL 1 or JAR FCL 2, as applicable to the aircraft to be flown.
4.3 The attention of all pilots is directed to Safety Sense Leaflet No. 25 and appropriate guidance material as detailed above. CAA web guidance is currently being developed to address specific training and approval aspects for RNAV for all phases of flight.
4.4 Non-UK licence holders must have appropriate training, equivalent to the above, and meet the national requirements of their licensing authority.
5 Aerodrome Licensing
5.1 The CAA Safety Regulation Group (SRG) Aerodrome Standards Department has issued a Notice to Aerodrome Licence Holders (NOTAL) specifying the responsibilities and actions required of licence holders intending to introduce RNAV (GNSS) procedures.
6 Aerodrome Procedures
6.1 Individual aerodromes wishing to introduce an RNAV (GNSS) approach are to request the design of an instrument approach procedure using the following:
http://www.caa.co.uk/docs/7/dap_ta_ifprequestform.pdf
The request is to be made to the Head of Controlled Airspace Section at the Directorate of Airspace Policy (DAP).
6.2 To enable a design to be initiated, aerodromes must have an up-to-date obstacle survey that complies with CAP 232 Aerodrome Survey Information requirements. Where instrument flight procedures do not currently exist, or new procedures introduce markedly different flight profiles, aerodrome operators should be aware of the requirements of the Airspace Change Process published in CAP 725 Airspace Change Process Guidance Document. Both CAP 232 and 725 are available via the CAA website.
7 Aerodrome Operating Minima
7.1 RNAV (GNSS) Approaches. Aerodrome operating minima for RNAV(GNSS) approaches shall be calculated in accordance with the method published for Non-Precision Approaches in UK AIP AD 1.1.2 with a system minima of no lower than 250 ft MDH.
7.2 APV Baro VNAV Approaches. Instructions on the calculation of aerodrome operating minima for APV Baro VNAV approaches will be published prior to the introduction of these procedures.
8 Aerodromes
8.1 Currently five licensed aerodromes, as listed below, have approval for RNAV (GNSS) procedures. It is intended that these procedures will be available from 30 August 2007.
Blackpool
Durham Tees Valley
Exeter
Gloucestershire
Inverness
9 ATS Providers – Information
9.1 The CAA SRG Air Traffic Standards Department has issued an Air Traffic Services Information Notice (ATSIN) outlining the responsibilities and actions required of ATS providers at aerodromes intending to introduce RNAV (GNSS) procedures.
10 Pre-Flight Planning
10.1 Aircraft operators shall ensure that the appropriate coverage from GNSS is provided for the intended flight. Receiver
Autonomous Integrity Monitor (RAIM) availability prediction should take into account the GPS constellation predicted for the duration of the flight, NOTAM and avionics architecture eg, Baro aiding input. Software tools available on the Internet can be used for this purpose eg, AUGUR4 or through the aircraft navigation system RAIM prediction capability, if provided. In the event of a predicted, continuous loss of appropriate level of fault detection of more than 5 minutes for any part of the RNAV (GNSS) approach procedure, the flight planning should be revised eg, delaying the departure or planning a different approach procedure.
10.2 RAIM availability prediction software does not guarantee the service; they are tools to assess the expected capability to meet the required navigation performances. Because of failure of some GNSS elements, operators must be aware that RAIM, or GPS navigation altogether, may be lost while airborne which may require reversion to an alternative means of navigation. Therefore, pilots should assess their capability to navigate (potentially to an alternate destination) in case of failure of GPS navigation. 4 AUGUR has been developed by EUROCONTROL and is available at
http://augur.ecacnav.com/
11 Method of Operation
11.1 Standard air traffic control procedures for sequencing and separating aircraft will apply at all times during RNAV approaches.
11.2 Pilots shall request clearance to fly the procedure. Clearance to fly the procedure permits the pilot to fly in accordance with the published procedure, following the descent profile.
11.3 The approach commences at the Initial Approach Fix (IAF).
11.4 RTF Phraseology: Pilots should request clearance to fly the procedure using the phraseology:
‘(Aircraft c/s), request RNAV approach, via (Initial Approach Fix Designator), runway xx’.
Where traffic conditions permit, air traffic controllers shall clear the pilot to follow the procedure using the following phraseology:
'(Aircraft c/s), cleared RNAV approach, runway xx, (report at (Initial Approach Fix designator))'.
For traffic sequencing and to aid situational awareness, air traffic controllers may request the pilot to report when established on final approach track or to report at any other relevant point in the procedure. For example:
'(Aircraft c/s), report 2 miles from final approach fix'.
Air Traffic Controllers shall instruct the pilot to report at the final approach fix, using the phraseology:
'(Aircraft c/s), report final approach fix'.
When Air Traffic Control is aware of problems with the GNSS system, the following phraseology shall be used:
'(Aircraft c/s), GNSS reported unreliable (or GNSS may not be available (due to interference)):
In the vicinity of (location) (radius) (between (levels)).
OR
In the area of (description) (between (levels)):
'(Aircraft c/s), GNSS unavailable for (specify operation) (from (time) to (time) (or until further notice)).
Following a RAIM indication, pilots shall inform the controller of the event and subsequent intentions.
'(Aircraft c/s) GNSS unavailable (due to (reason eg, Loss of RAIM or RAIM alert)) (intentions)'.
'(Aircraft c/s) Loss of RAIM or RAIM alert (intentions)'.
11.5 After reaching the final approach fix, the pilot will continue to fly the procedure towards the next waypoint, normally the runway threshold. At the appropriate time, the pilot will either continue with the air traffic clearance received or will execute the Missed Approach Procedure (MAP).
11.6 Missed Approach Procedure: To expedite the introduction of RNAV (GNSS) procedures, the Missed Approach Procedures will be conventional, using ground-based navigational aids. These will be reviewed in due course and, after detailed discussions with the airports to determine optimum hold locations and required tracks, will be converted to full RNAV MAPs. Environmental consultation will need to be considered for any new tracks. Until then, all MAPs will be straight ahead to a designated altitude with GNSS track guidance being provided towards the missed approach turning point only. At the designated altitude, or Missed Approach Turning Fix (MATF), whichever is the earlier, the pilot should revert to conventional navigation and route to the holding beacon ie, by making a turn to the beacon or a turn with continued climb to holding altitude at the beacon.
11.7 Loss of Communications: In the event of communications failure, the pilot should continue with the RNAV (GNSS) procedure in accordance with published loss of communication procedures.
12 Point of Contact
12.1 Pilots, ATS providers or aerodrome operators seeking further information on the establishment of RNAV (GNSS) Instrument Approach Procedures should contact:
Head of Controlled Airspace Section
Directorate of Airspace Policy
CAA House
45-59 Kingsway
London
WC2B 6TE
Tel: 020-7453 6510
E-mail:
[email protected]