PBN & RNP-AR

Question 1

When and how can SLS be used?

Answer 1

MEA:
* Minima: must be LNAV/VNAV minima (not LPV)
* Equipment: aircraft must be SLS equipped
* Augmentation: RNP approach must be EGNOS augmented

11/06/24

Question 2

What does RAIM stand for?
What is it?

Answer 2

Receiver Autonomous Integrity Monitoring
This is an integral self-monitoring of GNSS position, which can happen if you have 24 operating GPS satellites. It identifies “good” signals and “bad” signals, and dumps the “bad” signals.
If you have less than 24 operating satellites, a ground based station is required for integrity monitoring.

03/11/24

Question 3

What augmentation systems are currently used for RNP-AR?

Answer 3

EGNOS
(European Geostationary Navigation Overlay Service)

03/11/24

Question 4

How is the accuracy of the GPS system ascertained?

Answer 4

Using the AUGUR prediction tool on the Eurocontrol website.

03/11/24

Question 5

What is meant by “RNP 0.3”

Answer 5

“Required Navigation Performance 0.3nm”
The aircraft position can be ascertained to within 0.3nm.

03/11/24

Question 6

What is the lowest system minima for a RNP-AR approach?

Answer 6

Currently, easyJet not authorised to use RNP-AR minima below 0.3nm.

03/11/24

Question 7

What are the 3 elements of RNP-AR?

Question 8

Where is the required RNP approach equipment listed?

Answer 8

FCOM > Procedures > Special Operations > Performance Based Navigation (PBN)

03/11/24

Question 9

How can you tell if the aircraft is capable of flying a SLS approach?

Answer 9

In the configuration summary in the eQRH.

11/06/24

Question 10

What does F-APP RAW mean?

Answer 10

FLS guidance is shown but must not be used. The approach must be flown with reference to raw data (NDB, VOR, LLZ etc).

11/06/24

Question 11

What is the difference between SLS and FLS?

Answer 11

SLS stands for SBAS Landing System
(SBAS = Satellite Based Augmentation System)
FLS stands for FMS Landing System

11/06/24

Question 12

How does SBAS work?

Answer 12

A network of precisely surveyed ground based monitoring stations (called EGNOS) pick up GNSS information and calculate a position error. The position error is transmitted back to the satellite, which then transmits an error correction to the aircraft’s MMR.

11/06/24

Question 13

Can you fly a SLS approach without EGNOS?

Answer 13

No. The EGNOS network is needed in order to receive the position error signal.

11/06/24

Question 14

When making a SLS approach, how is the vertical path calculated?

Answer 14

From GNSS signals with EGNOS corrections (“geometric”).

11/06/24

Question 15

Can you use SLS guidance on any RNP approach?

Answer 15

No. The approach type (top right) needs to state “RNP… EGNOS” in order to use SLS.

11/06/24

Question 16

What minima can be used if flying a SLS approach?

Answer 16

VNAV/LNAV minima
(not the LPV minima)

11/06/24

Question 17

If you want to fly a SLS approach, you must select this approach type in the FMGC. What other selections must you check?

Answer 17

In the RAD NAV page, check that SLS is selected.

11/06/24

Question 18

What is FLS?

Answer 18

FMS Landing System
Used for VOR/NDB and RNP approaches
(not RNP-AR approaches)

11/06/24

Question 19

In the PERF page of the FMGS, what selections (FLS/FINAL APP) should be made for flying:
* RNP-AR approach?
* VOR/NDB approach?
* RNP approach?

Answer 19

RNP-AR: FINAL APP
VOR/NDB: FLS
RNP: FLS

11/06/24

Question 20

What is the advantage of using FLS vertical beam (F-G/S) over using a traditional method of flying a Type A 2D approach?

Answer 20

• Inserting the OAT in the PERF-APPR page will automatically correct obstacle clearance.
• FINAL APP technique results in a level segment for succesful engagement. FLS allows for CDA and G/S from above.
• Localiser only approaches can use vertical F-G/S guidance

15/06/24

Question 21

If flying a FLS approach, do you need to select the LS PBS or not?

Answer 21

Yes.

15/06/24

Question 22

Passing 10,000ft in descent, what must be checked if flying a FLS approach?

Answer 22

GPS Primary on at least one FMS.

15/06/24

Question 23

If flying a LOC only approach, what modes would you expect to see armed on the PFD when pressing the APPR PB when on an intercept heading?

Answer 23

LOC and F-G/S

15/06/24

Question 24

What are some key limitations of FLS?

Answer 24

• Curved final approaches are not supported, so cannot be used for RNP-AR
• Final approach leg and runway track must be less than 50°
• Still susceptible to incorrect QNH settings
• LPV minima are not usable (yet)

15/06/24

Question 25

What are the differences between the G/S from above procedure and the F-G/S from above procedure?

Answer 25

None.

15/06/24

Question 26

If flying a FLS approach, what height AGL will the message DISCONNECT AP FOR LDG appear?

Answer 26

150ft

15/06/24

Question 27

VOR, NDB, LOC approaches:
FLS capability downgrades to F-APP + RAW, what must you do?

Answer 27

Approach can continue in FLS, but lateral navigation must be crosschecked against raw nav data and distances/altitudes must be checked against charts.

15/06/24

Question 28

VOR, NDB, LOC approaches:
FLS approach capability downgrades to RAW ONLY. What must you do?

Answer 28

VOR, NDV approaches: deselect LS PB, revert to TRK/FPA guidance.
LOC approaches: may continue with LS PB selected, following the LOC. But vertical guidance must be in a selected mode, disregarding the F-G/S.

15/06/24

Question 29

You are flying a RNAV(GNSS) approach with LNAV or LNAV/VNAV minima. What are the actions in event of GPS PRIMARY LOST or NAV ACCUR DOWNGRAD?

Answer 29

Providing the fault occurs on only one ND or FMGS, continue the approach using the remaining one.

15/06/24

Question 30

You are flying a RNAV(GNSS) approach with LNAV or LNAV/VNAV minima. What are the actions in event of:
F-APP capability lost?
F-LOC deviation exceeding 1 dot?
NAV FM/GPS POS DISAGREE?

Answer 30

Discontinue approach (or continue visually, if possible).

15/06/24