RNP AR 2 Flashcards
What contingency procedures may be needed following a go around on an RNP AR approach?
Crew shall immediately revert to laterally selected mode (HDG/TRK) when NAV guidance is not adequate
Contingency procedures in some cases will be specified in the CCI
Contingency for generic procedures normally follow standard missed approach, radar vectors or conventional navigation
What are some failures relating to navigation where an RNP AR approach may be continued?
GPS (MMR) FMGS EFIS DU MCDU AP
What are some failures relating to navigation where RNP AP approach must be discontinued (unless visual references are sufficient)
FINAL APP does not engage GPS Primary lost on both NDs Dual NAV ACCUR DOWNGRAD FM/GPS POSITION DISAGREE FMS1/FMS2 POS DIFF Dual loss of FMGC or dual loss of FINAL APP Dual AP failure if RNP <0.3 Loss of GPWS TERRAIN function in case of inconsistancies affecting obstacles or terrain computation NAV ALT DISCREPANCY
What is the difference between RNAV and RNP?
Systems fundamentally similar, however RNP requires onboard performance monitoring and alerting
What is the difference between RNP and RNP AR?
RNP AR allows the addition of curved paths with RNP values <0.3
What is the lowest minima permitted by RNP operations? And RNP AR?
Both 250ft
What does navigation specification mean?
Aircraft and pilot requirements needed within a defined airspace
What are the enroute RNAV navigation specifications?
RNAV 10 and RNAV 5
What are the terminal RNAV navigation specifications?
RNAV 1 and RNAV 2
What are the RNP Enroute navigation specifications?
RNP 4
What are the RNP terminal navigation specifications?
RNP 1
What are the RNP approach and departure navigation specifications?
As specified in the chart
How accurate is RNP-X?
Has an accuracy > Xnm 95% of the time
What happens if EPE > RNP?
NAV ACCUR DOWNGRAD (displayed on ND and PROG)
What does MMR stand for? What does it do?
Multi-mode receiver. It takes data from GPS and sends it to ADIRU
What is the process for the data displayed on ND1?
GPS1 sends to MMR1, sends to ADIRU1. A hybrid IRS/GPS1 position calculated to FM1, giving FM1 position. FM1 position used by AP1 and displayed on ND1
IRS/GPS1 information is sent to FM1. Where can you find information solely from GPS1?
Onside MCDU under GPS Monitor page
Which GPS information is used for the terrain display on each display?
Both ND terrain displays come from GPS1
What does RAIM stand for?
Receiver Autonomous Integrity Monitoring
How many satellites needed for fault detection and exclusion (FDE)?
Minimum 6
How many satellites needed for fault detection (FD)?
Minimum 5
Why is onboard RAIM not always reliable?
It has a mask angle of 5 degrees, so in a high-terrain environment, the onboard prediction tool may not be sufficient, as terrain may be masking satellite information
How many satellites needed for GPS primary?
Minimum 5. Usually at least 6 will be available. If there is 5, and a short GPS outage, GPS Primary will still be available due to ADIRS
What are ‘error budgets’ in RNP AR procedures?
Adequate lateral and vertical obstacle clearances
What is path definition error (PDE)?
The gap between the trajectory displayed on the navigation charts and the lateral flight plan on the NDs. This error is negligible if correct quality processes are adhered to.
It is in both the lateral and vertical plane, representing difference between desired vertical path, desired lateral path, and actual path
What is XTK? Where is it represented?
Deviation from the lateral flight plan. It is shown on the ND, at the bottom, depicted by the yellow aircraft being left or right of the intended flight plan. It may say something like 0.08R, which means aircraft is to the right of the desired track.
It is also represented on the PFD by the L/DEV
How wide is the lateral obstacle clearance on RNP AR approach?
Twice the RNP value
What is the operational limit of lateral deviation on RNP AR?
Equal to the RNP value
What is the PM call for lateral deviation on RNP AR approach?
LAT-DEV
When should PM call ‘LAT DEV’
During an RNP AR approach, when L/DEV is half a dot
