Visibility comfort zone
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Visibility comfort zone
I am interested to know what viz people are comfortable flying an approach in.
To expand in conditions of haze (but not cloud) for a visual approach without any instrument approach aids at what level of visibility would you takle the approach and expect to get in.
Take the same question, but in the second instance, how would that change where there was a non precision instrument approach available.
I appreciate that whether the approach is into the sun or not may change your view so by all means take that or anything else you wish into account. It would also be interesting to know if you have some form of instrument rating or are VFR only.
Please ignore precision approaches on an localiser or ILS.
To expand in conditions of haze (but not cloud) for a visual approach without any instrument approach aids at what level of visibility would you takle the approach and expect to get in.
Take the same question, but in the second instance, how would that change where there was a non precision instrument approach available.
I appreciate that whether the approach is into the sun or not may change your view so by all means take that or anything else you wish into account. It would also be interesting to know if you have some form of instrument rating or are VFR only.
Please ignore precision approaches on an localiser or ILS.
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Fuji Abound
I think your question ignores recent improvements in avionics. I suspect that an experienced VFR pilot could fly an approach in zero vis using synthetic vision down to 150ft no problem. Conversely, an IR pilot with traditional equipment but no formal approach would not be able to get as close. I am ignoring the legality issue.
Rod1
I think your question ignores recent improvements in avionics. I suspect that an experienced VFR pilot could fly an approach in zero vis using synthetic vision down to 150ft no problem. Conversely, an IR pilot with traditional equipment but no formal approach would not be able to get as close. I am ignoring the legality issue.
Rod1
Interesting question, but hard to say.....It would depend to a large degree how familiar I was with the airfield. I usually fly a VFR only cub, no DI or AH, and get quite edgy cross country at less than 3 km visibility even at cub speeds. (No nav aids, no GPS) I would certainly be more at ease in the circuit at that vis, but I don't often do circuit bashing for the sake of it, as I get plenty of approaches when tugging. And of course glider pilots don't like flying inside a milk bottle either, so I tend not to have to do poor visibility approaches. I have a lapsed IMC and about 50 hours real instrument flying, if that helps to classify me, lapsed CPL, now flying on PPL.
So, to answer as best I may, about 1 km which is a bit over the length of our grass runway would take me to my discomfort zone. I would expect to get in, but not to want to make a habit of it.
If I had an NDB available I doubt if it would make a lot of difference at my home base, but it would be nice to have at an unfamiliar airfield, at least to point me at the runway. Runway lighting would help too!
So, to answer as best I may, about 1 km which is a bit over the length of our grass runway would take me to my discomfort zone. I would expect to get in, but not to want to make a habit of it.
If I had an NDB available I doubt if it would make a lot of difference at my home base, but it would be nice to have at an unfamiliar airfield, at least to point me at the runway. Runway lighting would help too!
For a purely unaugmented visual approach, I'd be happy at VMC minima in most aeroplanes with an approach speed under 60kn, with an easily visible runway.
Start making the runway less clear, or more importantly, the obstacles around it, or increasing the approach speed, and I'll start looking for better visibility.
G
Start making the runway less clear, or more importantly, the obstacles around it, or increasing the approach speed, and I'll start looking for better visibility.
G
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An impossible Q to answer because one does not have a long tape measure protruding from the front of the plane 
but I suppose I would fly down to 3000m or so.
I would use the GPS OBS to find the airport, track in the extended runway centreline, and descend down to circuit height (1000ft AGL) at about 2nm. That is about 3700m away and one could descend down from there.
Enroute I am not at all bothered by IMC. VFR to IFR is one continuous spectrum and the flying is all the same. My nav is 100% radio nav.
For a departure, I like to see down the runway to make sure there is nobody on it, but would be happy to depart in about 500m, with a backtrack along the whole length. In the USA a zero-zero departure (Part 91) is 100% legal and I think it is also OK here, Class G.
That's true but it is a bit of a psychological leap to trust it, down to 150ft visibility which assuming a ~3-5 degree approach is awfully close to the ground.
but I suppose I would fly down to 3000m or so.I would use the GPS OBS to find the airport, track in the extended runway centreline, and descend down to circuit height (1000ft AGL) at about 2nm. That is about 3700m away and one could descend down from there.
Enroute I am not at all bothered by IMC. VFR to IFR is one continuous spectrum and the flying is all the same. My nav is 100% radio nav.
For a departure, I like to see down the runway to make sure there is nobody on it, but would be happy to depart in about 500m, with a backtrack along the whole length. In the USA a zero-zero departure (Part 91) is 100% legal and I think it is also OK here, Class G.
I suspect that an experienced VFR pilot could fly an approach in zero vis using synthetic vision down to 150ft no problem
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I suspect that an experienced VFR pilot could fly an approach in zero vis using synthetic vision down to 150ft no problem.
Setting aside an approach to landing, the VFR pilot in instrument conditions faces the daunting task of keeping the airplane upright, let alone flying an approach. "Synthetic vision" is good and well, but I've seen a number of pilots with decent situational displays lose control of the airplane in straight and level flight, to say nothing of simple turns, or maneuvering.
We've already got idiots letting parachutes lure them into flying situations where they have no business. Let's not allow the same latitude to a pretty display.
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As a low hours pilot, not very!
I nearly wet myself arefter taking off later in the afternoon on a 'brewing' day (weather closing in from the SE and the NW full of CB)
The low sun created a haze layer which totally obliterated all downward vision directly forward, i could not see the airfeild or the surrounding hills and could not judge if i was inside or outside NZWB airspace, and i was very early solo.
Never Again.
I nearly wet myself arefter taking off later in the afternoon on a 'brewing' day (weather closing in from the SE and the NW full of CB)
The low sun created a haze layer which totally obliterated all downward vision directly forward, i could not see the airfeild or the surrounding hills and could not judge if i was inside or outside NZWB airspace, and i was very early solo.
Never Again.
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10k is my comfort zone in SEP's. 
I get paid to fly in ****e wx I don't see why I should fly in it for fun and I class instructing as fun.
Apart from which a good rule of thumb is to use the min viz on the circling approach along with the min altitude circling height. Stops you bumping into things.
I get paid to fly in ****e wx I don't see why I should fly in it for fun and I class instructing as fun.
Apart from which a good rule of thumb is to use the min viz on the circling approach along with the min altitude circling height. Stops you bumping into things.
