A/C landing in CAT I with 200 m RVR

[Spitoon]

Im sure the tower was aware of this incorrect reading hence gave you a clearance to land.

Not condoning anyone who chooses to land below minima or who thinks it's OK to do so but in Lord Spandex's example (which is in the UK) the RVR was not incorrect, it was the measured RVR and this is what gets reported. As a general principle, again in the UK but also in many other States, ATC does not question a pilot's operating minima and will not withhold a landing clearance because of the weather.

Just about anyone involved with operations at Edinburgh soon becomes familiar with the 'Gogar Burn problem'. The standard position for siting RVR measurement equipment runs alongside a small river called the Gogar Burn and in the right conditions shallow fog forms over the river and can easily drift toward/over the RVR transmissometers resulting in low RVR values. It can be frustrating to clearly see the airport and runways from a few thousand feet up and be prevented from making an approach but it's better than having aircraft mishaps because the pilot's view becomes far less clear when on short final. If I recall correctly there was at least one accident where this was a major contributory factor before the rules about approach minima were tightened up.

As a controller I saw a good few carriers repeatedly land in conditions where it was hard to believe that the necessary visual conditions existed from the flight deck. I chose not to use those carriers for my travel.

If any procedures were clearly breached or disregarded I would take the appropriate reporting action. If a pilot (or carrier) routinely feels that some rules can be broken what confidence can you have that any other rules will be respected?

[de facto]

Spitoon,

I agree with all that you wrote,but as a tower controller,you should know cat 1 minima right?if all your rvr report 200 meters and looking outside looks like 200 meters,ther is a big chance the pilot will not see approach lights by the standard 200 ft.
At 550 rvr,pilot will just start to see the approach lights at 200 ft,runway about 150-100feet.
At 200rvr(having flown actual cat 3a ),the visual will be between 50-70 ft.

I think the approach ban is to avoid crew to duck under and should be inforced by ATC.
There is a difference of lets say rvr decreasing from 550 to 500 rvr after the approach ban altitude as 50 meters may not necessarely be such a big drop not to have the required lights by DA.
200 rvr is just not possible with cat 1 minima.

Some airports may have local issues for their rvr readings but At the airport i was mentionning,the all airport was in fog,i barely saw the eurolot taxiing in front of my aircraft,it took off....
Now the airport in question is cat 1, no fences around,just a big forest

[askell]

On this APT like on many others, RVR meters are above the grass and might give inaccurate information, in some conditions where fog develops above humid surfaces and not over the RWY. We can observe this from te ground from time to time. Anyway, as soon as RVR is transmitted and even if we can observe that actual conditions are better, we don't take off, as it's not legal.

From the air, you can sometime see the runway from 50 NM, but if RVR is below 550 m, we hold or we divert: we know that we may see it till 50 ft and then lose all references just before touchdown. AS we are not LOTO players but professional pilots, we don't guess, we follow the rules.

[Lord Spandex Masher]

Originally Posted by de facto

Im sure the tower was aware of this incorrect reading hence gave you a clearance to land.

Well yes, but they were using LVPs and we were using a CAT II approach.

Just a bit odd carrying out a CAT II in anger when it was, effectively, clear as a bell.

[Spitoon]

I agree with all that you wrote,but as a tower controller,you should know cat 1 minima right?if all your rvr report 200 meters and looking outside looks like 200 meters,ther is a big chance the pilot will not see approach lights by the standard 200 ft.

Yup, I've got a pretty good idea about operating minima and AWO. But the point I was making is that in the UK (and a good few other States) the responsibility for operating the aircraft lies with the pilot and ATC provides information and instructions to assist the pilot. This general principle is applied throughout ATC procedures with very few exceptions and most pilots - quite understandably - fiercely protect their authority in this respect.

I do not condone pilots who bust the approach minimum or who creatively interpret the rules in other ways. But I do believe that the rules should be followed - if you don't think the rules are good there are channels through which you can attempt to get them changed. But the bottom line is that the rules are the rules and if individuals pick and choose which ones they wish to follow no-one can rely on the actions of anyone else. Aviation achieves almost incredibly good safety performance and much of this results from the comprehensive and effective rules.

If anyone chooses to break the rules without good justification I have little sympathy when they have to pay the resulting penalties. But the 'police' are the relevant supervisory/regulatory authority, not ATC (any more than it is pilots). Apparent infringements should be reported and appropriately investigated and the results acted upon by the CAA or whatever. The problem seems to be that this latter part of the system often seems to be ineffective.