Originally Posted by FlyingForFun
Although the increase DA/MDA I've described above is just a recommendation, the increased visibility for IMC ratings vs IR is mandatory. It is 1800m for both take-off and landing. In the case of landing, what this means is that, on an approach, you may not descend below 1000' agl if the vis is less than 1800m. However, once you have descended below 1000', if the visibility subsequently deteriorates to below 1800m, you may still continue the approach, and you may land if you have acquired the necessary visual reference before DA or MApPt.
FFF,
You seem to have confused the approach ban and landing minima. They are two separate things.
An IR holder requires the RVR to be above the applicable minima before commencing an approach or descending below 1000ftAAL. If after passing the 1000ftAAL or equivalent point the RVR reduces, the IR holder can land provided that at DA or MDA, they have the required visual references. Thus the IR holder while limited in RVR to commence an approach can actually land in any RVR provided the visual references are available.
The IMC Rating holder on the other hand is also limited by the requirements of the approach ban (note some approach minima may be greather than 1800m RVR eg circling). But the IMC rating holder is
also legally required by the ANO to have 1800m to land.
Thus for the IMC holder, the RVR reducing below 1800m even when below 1000ftAAL will require that a landing is not made.
In fact should the IMCrating holder become "visual" at say 1000ft but find that the flight visibility below cloud is only 1500m then since they do not have 1800m, they can not legally land despite perhaps having the threshold in sight.
Regards,
DFC