At least for N-reg it is the FAA.
JasonC wrote:
Not sure allowed in Europe any more. Reported RVR is usually constraining.
Correct. A pilot assessment can replace reported met vis, but not reported RVR.
AMC1 NCO.OP.110 Aerodrome operating minima — aeroplanes and helicopters
TAKE-OFF OPERATIONS
(a) General:
(1) Take-off minima should be expressed as visibility (VIS) or runway visual range (RVR) limits, taking into account all relevant factors for each aerodrome planned to be used and aircraft characteristics. Where there is a specific need to see and avoid obstacles on departure and/or for a forced landing, additional conditions, e.g. ceiling, it should be specified.
(2) When the reported meteorological visibility is below that required for take-off and RVR is not reported, a take-off should only be commenced if the pilot-in- command can determine that the visibility along the take-off runway/area is equal to or better than the required minimum.
(3) When no reported meteorological visibility or RVR is available, a take-off should only be commenced if the pilot-in-command can determine that the RVR/VIS along the take-off runway/area is equal to or better than the required minimum.
A pilot assessment can replace reported met vis, but not reported RVR.
So with a departure in say 200m, at an airport where no RVR is reported, the pilot cannot be prosecuted (unless there is a witness in the cockpit, presumably).
Especially as with vis anywhere near 400m the tower may not see the runway at all.
That is very interesting!
We did this a while ago regarding arrivals and the approach ban, where no RVR was reported, and that IIRC was different i.e. the ATC-reported vis was applicable.
Just saying that the min RVR is actually 800m unless you have a coupled Autopilot
Granted most have this, but I wonder what coupled means… for example in the C82T in my club, the A/P does not descend on the glideslope
Peter wrote:
We did this a while ago regarding arrivals and the approach ban, where no RVR was reported, and that IIRC was different i.e. the ATC-reported vis was applicable.
Yep and there is a table and a formula explaining which is the correction coefficient applicable to convert the met vis into CMV in GM4 NCO.OP.110
