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Keen to get this question about RNP tolerances answered
BushPilot8 created the topic: Keen to get this question about RNP tolerances answered
G'day,
I"m about to do my Instrument Rating, and after looking through the MoS on page 690 of Schedule 8, it specifies the 2D approach Lateral Path Tracking Tolerance to be within the RNP value specified for the published minimum altitude.
May someone please explain what that is referring to? I'm confused as the sentence above mentions half scale deflection to be the tolerance, however the one mentioned above sounds like providing you are within full scale deflection (i.e. within 1 mile during terminal mode and 0.3 miles during approach mode) then you are within tolerances.
Any assistance will be greatly appreciated.
Picture attached
bobtait replied the topic: Keen to get this question about RNP tolerances answered
For any segment of an RNAV/GNSS approach there are two tolerances to consider.
For example, on the final approach segment of an RNAV/GNSS procedure the two tolerances are-
(1) The horizontal integrity limit (HIL) which is 1nm (full scale defection) for the final approach segment of an RNAV/GNSS procedure
and
(2) The tracking tolerance applied by AIP ENR 1.1 para 4.6.2.
If the aircraft deviates beyond the HIL on the final approach segment, a RAIM warning will be triggered and a missed approach should be initiated.
Within half scale deflection of the CDI, the procedure may be continued. Between half scale and full scale deflection, immediate action must be taken to re-establish a track withing half scale defection,