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Area Navigation - RNAV Approach And Landing Procedures

David Szymanski - ENACMay 2013

PLAN

• Instrument flight Procedure

• RNAV

• GNSS Approaches:

– LNAV (Lateral Guidance)

– APV BaroVNAV (Lateral + Vertical)

– APV SBAS

– GBAS

• Instrument flight Procedure

• RNAV

• GNSS Approaches:

– LNAV (Lateral Guidance)

– APV BaroVNAV (Lateral + Vertical)

– APV SBAS

– GBAS

Instrument Flight Procedure?

• Series of predetermined manœuvres by

reference to flight instruments

• These manoeuvres are based on facilities or

way-points for aircraft proceeding according to

Instrument Flight Rules ( IFR )

REGULATION

• ICAO regulation

– DOC 8168-OPS/611 (Volume I and II) : procedure design

– Annex 11 : Radio Navigation aids

– Annex 14 : Aerodrome Design and Operations

– Annex 4 : Charting

– Annex 15 : Aeronautical Information Services

• National regulation

– France

– USA, Canada

– Others

DOC 8168-OPS/611

• Design of instrument flight

procedures

– En-route

– Arrival

– Approach

– Departure

• RNAV

• Conventional navigation

IAF

IF FAF

MAPT

TP

HOLDING

INITIAL INTERMEDIATE

FINAL

MISSED APPROACH

Approach segments

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Fixes and Segments

Straight Radioguided segment

Curve radioguided segment

Dead-reckoning segment

AIRCRAFT CATEGORY

• Five categories : From A to E (H) :

– Max and Min Speed (IAS) known by pilots and designers

(regulation tables)

• Possible speed limitation

– Obstructions

– ATC constraints

– Environmental contraints

– MUST be displayed on the chart

INITIAL

APPROACH

FINAL

APPROACH

CIRCLING MISSED APPROACH

Maximum speedCat.

Vat

Min Max Min Max Max Initial andIntermediate

Final

A <<<< 91 90 150 (110*) 70 100 100 100 100

B 91 / 120 120 180 (140*) 85 130 135 130 150

C 121 / 140 160 240 115 160 180 160 240

D 141 / 165 185 250 130 185 205 185 265

E 166 / 210 185 250 155 230 240 230 275

SPEEDS TABLE : IAS

unit kt

PROTECTION AREA

• Protection area data

– Nominal trajectory

– Flight technical tolerances (FTT)

– Fix tolerance

– Wind effect

• Segment protected by a protection area

Fix 1Fix 2

Fix 3

FTT : Reaction delay

Bank delay

Consecutive segments PLAN

• Instrument flight Procedure

• RNAV

• GNSS Approaches:

– LNAV (Lateral Guidance)

– APV BaroVNAV (Lateral + Vertical)

– APV SBAS

– GBAS

• Instrument flight Procedure

• RNAV

• GNSS Approaches:

– LNAV (Lateral Guidance)

– APV BaroVNAV (Lateral + Vertical)

– APV SBAS

– GBAS

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RNAV: AREA NAVIGATION

Shorter Routes ….

More Routes Possible ...

RNAV approach trajectory

RNAV POSITIONING METHOD

• The RNAV system

– identifies the next waypoint,

– selects the most appropriate source of

navigation to determine its position

– provides information to the auto-pilot to fly

to the next waypoint.

• An RNAV route can be flown manually

WAYPOINT

• Waypoints expressed in WGS84 coordinates

– IAF, IF, FAF, MAPt, MAHF

– Arrival or departure waypoint

Fly-over waypoint

Fly-by waypoint

WP1 : FLY-OVER WP2 : FLY-BY

Stabilization distances are necessaryALL RNAV TRAJECTORIES ARE CODED

INTO THE DATABASE

On board database

••Aerodrome data Aerodrome data

••Available navaidsAvailable navaids

•Flight paths to follow

(charts)

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Departure chart

CF

DF

DF

TFTF

CODING INFLUENCE

CONSTRAINTSCONSTRAINTS

How to navigate

PATH TERMINATOR

How to navigate

PATH TERMINATOR

PATHPATH

TF : TRACK BETWEEN FIXES

Usable by all systems

Preferential path terminator

DF : DIRECT TO FIX TF Protection

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DF Protection Semi Area Width for RNAV

RNAV 5 EnRoute 5.77 Nm

RNAV 1 / RNAV 2More than 30 Nm 5 Nm

Less than 30 Nm 2.5 Nm

RNP APCH

Initial/ Intermediate 2.5Nm

Final 0.95Nm

Missed Approach 2 Nm

Type of waypoint

PATH Terminator

Coding influence

Nominal trajectoryProtection Area

PLAN

• Instrument flight Procedure

• RNAV

• GNSS Approaches:

– LNAV (Lateral Guidance)

– APV BaroVNAV (Lateral + Vertical)

– APV SBAS

– GBAS

• Instrument flight Procedure

• RNAV

• GNSS Approaches:

– LNAV (Lateral Guidance)

– APV BaroVNAV (Lateral + Vertical)

– APV SBAS

– GBAS

GNSS integrity monitoring

• GNSS integrity monitoring techniques aim at monitoring GNSS positioning

• Large variety of techniques:

– In an autonomous manner (ABAS) :

• Using only redundancy of GNSS measurements (RAIM)

• Using additional information from other sensors (AAIM)

– Using a ground station (GBAS)

– Using a network of ground stations (SBAS)

ICAO GNSS CONCEPTGLOBAL NAVIGATION SATELLITE SYSTEM

AUGMENTATION

SATELLITEBASED(SBAS)

GEOSTATIONARY

EGNOS

WAAS

MTSAS

GROUNDBASED(GBAS)

ON BOARDABAS)

A.A.I.M

R.A.I.M

GAGAN

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Approche GNSS : RNP APPROACH

• RNP APCH = Sensor used GNSS with Augmentation

• RNP 1 (1 NM of Accuracy) for initial, intermediate and missed approach segments

• RNP 0.3 for final

• No vertical guidance :

– LNAV

• vertical guidance :

–– Baro VNAV, SBAS, GBAS Baro VNAV, SBAS, GBAS

WHICH AUGMENTATION FOR WHICH KIND

OF APPROACH ?

ABAS Non Precision Approach NPA

+ VNAV: APproach with Vertical Guidance APV baroVNAV

SBAS APproach with Vertical Guidance

APV I and II

GBAS Precision Approach

PLAN

• Instrument flight Procedure

• RNAV

• GNSS Approaches:

– LNAV (Lateral Guidance)

– APV BaroVNAV (Lateral + Vertical)

– APV SBAS

– GBAS

• Instrument flight Procedure

• RNAV

• GNSS Approaches:

– LNAV (Lateral Guidance)

– APV BaroVNAV (Lateral + Vertical)

– APV SBAS

– GBAS

Non Precision Approach : LNAV

LNAV Protection Areas LNAV : OCH Computation

• Assessment of Obstacles in Protection

Area : Hobst

• Add MOC (Minimum obstacle Clearance)

– Same whatever the Aircraft Category

• OCH = Hobst + MOC

• Minima Box Line : LNAV

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RNAV NPA :

LNAV Approaches

• 2D RNAV = LNAV

• RNAV system provides

lateral guidance in final

segment

– ABAS as minimum

HOW TO FLY VERTICALLY NPA ?

• Two different ways to FLY vertically :

– ‘Dive and Drive’

– ‘Stabilized approach’

• NO CONSEQUENCE on PROCEDURE

DESIGN

DIVE AND DRIVE

• Descend immediately to not below minimum step-

down fix altitude or MDA/H as appropriate.

• Descent gradient < 15%

• Missed approach initiated at, or before MAPt.

STABILIZED APPROACH

(CDFA)

• Continuous descent gradient to

– a point 50 ft above the threshold

– taking regard of minimum crossing altitude at FAF

and step-down fixes.

• Missed approach initiated :

– Visual reference not achieved approaching MDA/H

– Not permitted below MDA/H at any time

– Not permitted after MAPt

CDFA

50 FTMOC

MDA

MAPtDIVE and DRIVE

CDFA : A specific METHOD OF FLYING the FINAL approach segment of NPA on pre-determined approach slope with continous descent to DA (H)

CDFA : Continuous Descent Final

Approach

3°°°°

FAF

Dive and Drive mode

Stabilized approach

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APV : Approach with Vertical Guidance

APPROACH PROCEDURE WITH VERTICAL

GUIDANCE

• APV Approach Procedure with Vertical guidance:

An instrument procedure which utilizes lateral and vertical guidance but DOES NOT MEET the requirements established for PRECISION APPROACH and landing operations

• LATERAL and VERTICAL GUIDANCE in the FINAL segment

• 2 Types– APV SBAS

• SBAS receiver on-board

– APV BaroVnav• ABAS + VNAV capability

RNAV APV : SBAS

APV SBAS Protection Area (1)

APV SBAS Protection Area (2) APV SBAS (LPV) : OCH Computation

• Based on ILS methodology

• Obstacle Assessment Surfaces (W, W*, X, Y, Z)

• Height Loss (HL) instead of MOC (Vertical Guidance)

– Different Value for each Aircraft Category

• When penetration of obstacle

OCH = Hobst + HL

• Minima Box Line : LPV

– Different value per Aircraft Category

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APV SBAS integrity

• Final Approach segment

integrity through a FAS

Data Block (including CRC)

• FAS Data Block in the SBAS

System

• Publication of FAS Data

block in AIP

APV SBAS :

LPV Approaches

• APV SBAS = LPV

• RNAV system

provides lateral and

vertical guidance in

final segment

– SBAS

RNAV APV : Baro VNAV

APV Baro VNAV : Protection Area

APV Baro VNAV OCH Computation

• Temperature dependant

• Obstacle Assessment Surfaces (FAS, Horizontal

Plane, Z)

• When penetration of obstacle

OCH = Hobst + MOC

• Minima Box Line : LNAV / VNAV

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APV Baro VNAV :

LNAV / VNAV• APV Baro VNAV = LNAV /

VNAV

• RNAV system provides

lateral and guidance in final

segment

• Vertical guidance through

Barometric altimeter

• RNAV System:

– ABAS + VNAV system

APV Baro VNAV : On going criteria

• On going criteria for Baro VNAV :

– Consistency with all vertical guidance (ILS,

MLS, SBAS, GBAS)

– Use of HL instead of MOC

– Different Position of surfaces regarding

existing criteria

RNAV Precision Approach : GBAS

APV GBAS (LPV) : OCH Computation

• Same principle as SBAS

• Obstacle Assessment Surfaces (W, X, Y, Z)

• Height Loss (HL) instead of MOC (Vertical

Guidance)

• When penetration of obstacle

OCH = Hobst + HL

RNAV GBAS : PRECISION

APPROACH

• LATERAL and VERTICAL

GUIDANCE in the FINAL

segment

– Only with GBAS

augmentation

• FAS Data Block send by

ground station to Aircraft

↸↸↸↸

PRECISION APPROACH

•Horizontal guidance•Vertical guidance

FAFMAPt

OCHMOC

HLOCH

FAP

DHDH

MDHMDH

NON PRECISIONAPPROACH

•Horizontal guidance

APPROACH with vertical guidance

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SUMMING UP

Type of approachType of

guidanceMDA or DA Minima line

NPA lateral MDA LNAV

APV baroVNAVLateral

VerticalDA LNAV/VNAV

APV SBASLateral

VerticalDA LPV

PALateral

VerticalDA

Title of procedure :

GLS

• Approaches are based on GNSS

– In PBN vocabulary : RNP APCH

– In AIS document : RNAV (GNSS)

• All different vertical guidance in one chart

(same Final + missed approach)

Publication

Captureregion

Capture Région

IAF

IAFIAF

IF

FAF

MAPt

70°

INITIAL

SEGMENT

INTERMEDIATE

SEGMENT

FINAL

SEGMENT

Captureregion

TF coding

Y BAR DESIGN CONCEPT

•Flight time reduction

•Aligned on runway centerline

•Improve visualization of markings and lightings

•Easy use ( piloting ,no misunderstanding )

Y BAR Concept KEY POINT

• Standardization

• Easy design

• All GNSS receivers NPA certified could

proceed T or Y procedure

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• Provide a vertical guidance

– ILS , APV BARO-VNAV, APV SBAS

• Provide a constant descent in final

approach

For CFIT PREVENTIVE MEASURE

KEY POINT CONCLUSIONS

• Different GNSS Approaches

• Only RNP APPROACH (NO RNAV)

• GNSS approaches : NPA, APV and PA

– Using augmentation:

» NPA : LNAV (ABAS)

» APV : - SBAS = LPV

- BaroVNAV = LNAV / VNAV

» PA : GBAS

• Obstacle assessment based on surfaces when

vertical guidance is provided (AV and PA)

GNSS+

VNAV+

ABAS receiver

BARO VNAV

WASS / EGNOS+

SBAS Receiver

APV SBAS

Computed vertical guidance and

barodependant

Geometric vertical guidance based on satellite information

Navigation Sensors associated with MDA

and DA

MDH higher than 300ft

NPA : GPS

HAL : 556m

HAL : 40m

VAL : 50m300ft< DH < 250ft

APV1 : SBAS HAL : 40m

VAL : 35m300ft< DH < 200ft

LPV200 : SBAS

EGNOS, Galileo

HAL : 40m

VAL : 15 to 10m200ft = DH

GBAS catI

HAL : Horizontal Alarm Limit

VAL : Vertical Alarm Limit