RVR and Visibility in ILS charts
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Never seen vis and RVR on the same report. At least not one where vis is lower than RVR. AFAIK, (in my country at least), below 800m, which is standard vis for takeoff, you need RVR. So in any case vis<800m, we need RVR before we can do anything, hence RVR is controlling. Vis is pretty much useless (legally) by that point
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Ah, having read the above is the “grey area”/the confusion down to the way the Ops manual is written/semantics? For some approaches the “controlling” minima will be a vis....for others it will be an controlling RVR...however the way the manual has been written has conflated the two.
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Hi there,
Let’s say an airport reported METAR visibility 0200, RVR 750. The requirements to shoot the ILS approach requires CAT 1 of Visibility 800m / RVR550m, The airport only has CAT 1 landing. I’m able to meet the RVR criteria but not the Visibility criteria, am I able to shoot the approach?
Let’s say an airport reported METAR visibility 0200, RVR 750. The requirements to shoot the ILS approach requires CAT 1 of Visibility 800m / RVR550m, The airport only has CAT 1 landing. I’m able to meet the RVR criteria but not the Visibility criteria, am I able to shoot the approach?
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Yes, the RVR is controlling.
At dispatch You will only have the forecasted visibility issued by the TAF. In Your example a RVR reading is available at destination so You are not allowed to use the conversion of reported meteorological visibility to RVR, hence if forecast vis +/- 1 hour is less than the required one for the approach You are considered below minima and need 2 suitable alternates to dispatch (EASA land).
At dispatch You will only have the forecasted visibility issued by the TAF. In Your example a RVR reading is available at destination so You are not allowed to use the conversion of reported meteorological visibility to RVR, hence if forecast vis +/- 1 hour is less than the required one for the approach You are considered below minima and need 2 suitable alternates to dispatch (EASA land).
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