Performance Based Navigation

Question 1

What navigation systems does PRB use and what systems does it replace?

Answer 1

Uses space based (GNSS)

Replaces ground sensor based aids (ILS, VOR, NDB)

Question 2

What does RNAV stand for? What requirements must it meet?

Answer 2

Area Navigation. An RNAV system must meet accuracy, integrity, continuity, availability and functionality requirements but need not have Performance monitoring and alerting

Question 3

What is the different between RNP and RNAV?

Answer 3

RNP requires on board performance monitoring and alerting

Question 4

What phase of flight is the RNAV2 specification used for in NZ?

Answer 4

All enroute operations

Question 5

What phase of flight is the RNAV 1 specification used for in NZ?

Answer 5

Standard specification for SIDs and STARs

Question 6

What phase of flight is the RNP1 specification used for in NZ?

Answer 6

SIDs and STARs at selected regional airports

Question 7

What is RNP APCH specification used for in NZ? How does it appear on charts?

Answer 7

RNP Approach is used at certain aerodrome in NZ. IT appears as RNAV(GNSS) on charts

Question 8

What is RNP AR specification used for in NZ? How does it appear on Charts?

Answer 8

It is used for certain approaches that requires CAANZ approval to make that approach. Marked as RNAV(RNP) on charts.

Question 9

What does the number mean on an RNAV or RNP specification?

Answer 9

It is the limiting number in nautical miles for the lateral deviation from the centreline of the track. It must be maintained at least 95% of the time.

Question 10

In normal conditions what should the ANP be when flying RNAV routes?

Answer 10

No more than half the maximum allowable.

Question 11

What are the letters used as Domestic ATS route designators?

Answer 11

Conventional 1 way: V
Conventional 2 way: H
RNAV 1 way: Y
RANV 2 way: Q

Question 12

What is the default RNP for; En-route, Terminal, Approach, Missed Approach?

Answer 12

En-route: 2.0mn
Terminal: 1.0nm
Approach: 0.3nm
Missed approach: 1.0nm

Question 13

What approaches will have vertical descent guidance and which ones will have only have lateral guidance?

Answer 13

VNAV provided:
RNAV(GNSS) - Where VNAV is specified
RNAV(RNP)

VNAV not provided:
RNAV(GNSS) - Where LNAV is not specified

Question 14

What are some characteristics of RNAV(GNSS) approaches?

Answer 14

• Straight tracks between waypoints
• RNP of 0.3
• Non-precision approach even where VNAV is given

Question 15

What are the characteristics of B-VNAV approaches?

Answer 15

• Uses barometric data to give vertical guidance
• Usually has descent gradient of 3˚
• Uses DA rather than MDA
• Vertical path angle of above and below ISA will be given
• QNH must be aerodrome specific

Question 16

What are the characteristics of RNAV(RNP) approaches? (9)

Answer 16

• Approach procedures with vertical guidance (APV)
• Requires Aircraft, aircrew and operator approval from CAA
• RNP will be 0.3nm - 0.1nm
• Mix of straight tracks and radius to fix tracks
• Flown at constant angle descents
• Require GNSS updating of FMS/RNAV navigation position
• Not allowed to use Remote QNH
• IAF and IF are often co-located
• FAF indicated by a Maltese cross

Question 17

Can non RNP aircraft operate in RNP airspace?

Answer 17

Yes, as long as it is not designated “RNP Mandatory”

Question 18

When designing RNAV routs, what is the lateral containment?

Answer 18

Track 2 time the RNP value either side of centreline is obstacle and terrain free

Question 19

How can you tell the difference between a fly by waypoint or a flyover waypoint?

Answer 19

Fly-by: normal

Fly-over: circle around symbol

Question 20

What are the 4 different types of legs? Briefly describe each?

Answer 20

• Track to Fix: Track between two points is intercepted and flown
• Direct to fix: Track from present position directly to next fix
• Course to fix: Path terminates at a fix with a specified course at that fix
• Radius to fix: A constant radius circular path around a defined turn centre that terminates at a fix

Question 21

What does RF required mean on an approach chart?

Answer 21

Radius to fix

Question 22

What is the terminal area of an RNAV route?

Answer 22

Tracks within a 30nm radius of the aerodrome reference point

Question 23

What is GBAS? How does it work? What is its accuracy?

Answer 23

• Ground based augmentation system
• Takes measurements based on its very accurately known location and transmits corrections DIRECTLY to the aircraft
• Generally a localised system relating to approaches and departures
• Less than 1m vertically and laterally

Question 24

What is SBAS? How dies it work? What is its accuracy?

Answer 24

-Space based augmentation system
-Ground stations detect small errors and transmit information to central computer
-Central computer calculates correction to apply to different zones
-Correction then transmitted to additional satellite
-Correction sent from satellite to the SBAS capable GPS receiver
Accuracy with mobile coverage is 3cm, without it is 10cm

Question 25

What are the errors of a GPS position outcome? What is each error?

Answer 25

• Path defined error: The hardwares ability to calculate the desired flight path from the nav database (usually negligible)
• Flight technical error: Difference between aircraft’s estimated position and the designed path. (Called Cross-track error)
• Navigation System Error: The difference between its estimated position and its true position
• Total System Error: Combination of all errors