Personal Flying Visibility Minima

[Barney_Gumble]

Hi All,

I am familiar with the visibility minima for "legal" flight for a PPL without an IMC rating and consider that I would not be happy to fly at this minima of 3km.

That started me thinking as to what minima I would be happy flying in. Well today I had a chance to try this out at EGKB and set off to complete some circuits with a viz of 5km at the beginning of the session rising to 7km at the end. The sun was quite low in the sky and I felt that I would not want to be flying at anything less than 5km viz.

From this I have deduced that I have a personal minima of:

5km for circuits and operations in site of the airfield
8km for x-country

I will use these figures as a guide to my Go/No Go decision making process, bearing in mind that flying is my hobby not my profession.

Does anyone else work on these kind on personal minima and if so do the figures above sound reasonable. I have a day VFR SEP licence with 102 hrs total of which 33 hours are P1

Advice warmly welcomed

Regards

Andy

[EyesToTheSkies]

BG,

Those limits seem reasonable to me. Last summer I was doing circuits at Stapleford in what I thought was around 4Km, and I was just at the edge of my comfort zone. The thought of going xc at that visibility did not seem a good idea. I've got 80-odd hours.

[tomcs]

I totally agree with you...i did a positioning flight from Old Sarum to Bournemouth this afternoon and the vis was terrible. I've just my IMC training so i was reasonably ok with it...despite having to use SAM VOR and the NDB at EGHH to get there.

I think 8km is minimum for me in VFR...but then IFR is a different ball game :P

Tom

[flickoff]

Dispite all the detractors the best money post PPL Ii spent was getting an IMC. Get one it is so useful, even if you do not fly IFR or even in an dial equipped a/c, the stuff it teaches you is inestimably useful. Nothing I have done before or since is of much value.

[AerBabe]

Seems like 8km vis for a x/country is about standard for the comfort zone. I flew with another qualified pilot from Coventry to the Forest of Dean area soon after getting my PPL, and when the vis was getting lower than 10km I was starting to feel uncomfortable. For circuits I'm okay with 3km vis, but not completely happy. I suppose that partly depends on the field you're doing circuits at. Coventry is fairly large, and there are lots of big ground features we use for the circuit pattern. The difficulty comes when the sun is shining through the cloud, and it's like flying through milk. Then it's impossible to spot traffic.

[bookworm]

There are at least four different reasons for wanting decent visibility, and the minimum that you pick may depend on the circumstances of the flight:

You may need visibility to control the aircraft. If you're not trained in instrument flying, you probably want a decent horizon to help keep straight and level.

You need visibility to avoid other aircraft. That may bother you more if you're heading for a busy GA airfield than if you're flying in a relatively remote area where the chances of encountering another aircraft are slim.

You need visibility to avoid terrain and obstacles. You need better visibility for flying in hills and mountains than you might be happy with in flatland. Seeing a hill a minute before you're about to hit it can be pretty stressful.

You need visibility to navigate (or you may not, depending on the methods of navigation you are trained in and intend to use). Visual navigation in visibilities of even 5 to 10 km can be very hard work. What you decide you need may depend on how difficult the task at hand is.

So while I'm not suggesting that a personal visibility minimum is a bad thing, please remember that different missions need different considerations.

[Go-on-Boy]

A couple of years ago I did a local flight, weather ok when left airfield, called for rejoin about hour later and was told by ATC that a shower was passing over the field vis down to about 4km. Like a fool said "please advise if it gets worse will come in", well when I got closer to the field it was hell, couldn't find the field but knew I was right near due to landmarks, this is a main airfield with full lighting etc! Eventually did manage to find one of the runways, more by luck then judgement, but oh boy what a mistake I made, should have stayed away for the shower to pass. This time I got away with it and a very valuable lesson learnt on my part, 4k vis and vfr just is a BIG no go in my book.

[Tinstaafl]

What's acceptable to you will change with your experience too.

In addition to bookworm's points it's helpful to consider time of day. Sun position has a significant effect on how much a given visibility is usable.

NB: Up here it's ops normal at 350' with 1000m vis & 40 -50kts... :eek:

[Barney_Gumble]

Good advice thanks. I like the comment regarding individual considerations based on the mission. I will use that in future.

My next question then is......

"Why is the UK legal minima set at 3km for PPL without IMC (in Class G)"

Consensus here, albeit from a small amount of respondents, would seem to suggest that this minima is too low; since we are not happy to operate under these conditions. Would it not be more prudent to raise this minima as it could indicate to VFR only PPLs that flying in this viz is acceptable, even though a majority may not have the necessary skills and/or currency.

I realise that there are very experenced VFR PPLs who would be happy to operate under these conditions and maybe the minima is set to enable these more experienced folk to enjoy this whilst generally keeping the decision of acceptable personal minima in the hands of the PIC.

[VORTIME]

10+ x-country
3+ circuits
7+ local

[28thJuly2001]

A PPL is supposed to be fun, where is the fun in flying around in 5km vis?
I don't go flying unless it is CAVOK and winds calm. :D
28th,,

[Flyin'Dutch']

28th

Take it you dont do a lot of flying in the UK then!

:D

FD

[28thJuly2001]

Waddayamean?????
I flew for 25 minutes at the end of August..... :p

Meanwhile back to the plot.. I am like the majority...5km is ok for circuits but I like 8km+ for anything more adventureous. As for wind,,, hmmm probably 20 knots is the maximum I feel comfortable with and a 10 knot xwind.
28th,,
p.s. I have just over 100 hours.

[lancer1]

How encouraging to read these posts, showing that I am after all not the only one to feel such an anxiety in poor vis.

Yesterday I flew for what was in any case to be a short local flight, well aware that wx was 4km and sunny. But once airborne I restricted myself to four circuits and came in. Like a number of others above, I agree that 4km vis is insufficient for me as a once- or twice-a-month PPL - I like to enjoy my flying.

Never mind, I'm off to Oz in May for 14 days of flying touring in fantastic conditions!

[niknak]

Forget what others say - know your limitations, and use common sense. If you're not happy, don't go.

[Lowtimer]

I imagine every PPL holder who has trained in the UK will have flown in poor visibility - I would hope that most did so as part of their course, while dual. Personally I found it an extremely valuable lesson that 3K / 2 miles visibility, while it seems fine to the lay person driving along the motorway, is seriously no fun in the air. But I would strongly resist tightening the law. Not everyone flies the same types in the same airspace, nor do they have the same skills and knowledge. What might be unsafe in a fast cruiser with limited field of view, in busy airspace, might well be safe in a 50 knot microlight doing a low level circuit out of a farm strip in the wilds of East Anglia.

[Final 3 Greens]

There are two issues here (I don't disagree with Bookworm, but just identiffy less categories.

(1) under what conditions can you keep control (including navigation) and (2) how do you feel about other a/c around you...

If I can see the surface then I can keep control (and radio navigate) - I know because I have found myself in this (uncomfortable) circumstance.

But even at 5km, how well can one see and avoid?

I tend to agree with 28th July - we PPLs fly to enjoy ourselves ... and pilots like TINSTAAFL have to cope because it's ther job.

I live near an ATPL who owns an SEP, which he will not fly in IMC. When I asked him why, he replied that he flew 'big iron' for a day job and the SEP for fun :D

[Barney_Gumble]

I tend to agree wih your comment about changing/tightening regulations Lowtimer the overiding factor is that the PIC should not take off unless they are confident that the flight can be completed safely, so the PIC uses his/her own judgement. This should remain the case IMHO.

[Doghouse]

Firstly, Barney Grumble, I think it's great that you have personal vis minima, though I'd make it a bit more flexible for the task as one of the posts suggests.

I would like to give you a perspective from a flying instructor and ferry pilot. For us, particularly the ferrying, we need low VMC minima if we're delivering to an airfield without approach aids. In fact, the CPL VFR minima goes down to 1.5km in class G below 140kts and 3000ft. Once you get the appropriate experience (and, of course, the ratings to know you can get in somewhere else if you have to), 3km vis is actually not too bad. Looking out for aircraft is an issue but a RIS can be a big help in that weather.

For private flying I probably wouldn't bother in vis like that because I want some fun and low vis would be too much like work. However, it is definitely worth going with an instructor in bad vis and learning implicitly to trust dead reckoning - it always works. From my experience, I'd say the biggest problem with poor vis is terrain and familiarity with the area helps.

For low hour PPLs, particularly without an IMC/IR, your minima are a good personal discipline, but I wouldn't want to lift the VMC/VFR minima to suit low hour pilots. The course is designed to help pilots make their own decisions and it sounds as if your instructor has done a good job with you.

[FlyingForFun]

It definitely depends on where you're flying.

While flying in the USA, I planned a flight from Phoenix to Los Angeles. It was the longest flight I've ever done, into an area where I'd never been before, where the air-space is extremely complex. Many hours of planning went into the flight, but by the morning of the flight, I was feeling confident.

I called for a briefing. The only significant weather was sand-storms, with vis down to 8 miles, and light to moderate turbulence. Quick conversion to kms, and I realised that 8 miles was well above my minimums, and the turbulence wasn't going to bother me, so I was set to go.

Well, 8 miles of visibility certainly isn't any problem flying around south-east England. But flying through the Californian desert, where visual navigation consists of heading from mountain to mountain, with each significant mountain around 30 to 40 miles from the next, was a little harder. And a bit of turbulence may not bother me when I know where I am, but I could really do with being able to write on my chart and on my plog without having the pencil knocked out of my hand at a time when I'm finding navigation a little tricky. It's the only time in my VFR flying career that I've had to absolutely rely on navaids for navigation. Fortunately, I had already planned to use navaids for backup, so I had all the details on my plog and chart before the flight. So the trip, although stressful, was safe, and I arrived at Los Angeles very tired but in one piece a few hours later, and a much wiser pilot.

FFF
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[Aussie Andy]

Excellent thread - was starting to feel a bit sub-par myself for not being comfortable below say 8km / 10km on a few flights last year, so good to know I am reacting same as other approx. 100 / 120 hr guys.

One mitigant that I sometimes consider is the presence of another PPL of equal or greater ability, which serves to halve the workload. Did trip to Blackpool ealier this year in approx. 5~6km vis. like this (other guy similar experience and also non-IMC rated), and it worked out well - but I know I would not have done so on my own.

Andy

[Flyin'Dutch']

Interesting CRM:

I know I would not have done so on my own

Never realised that having 2 vanilla PPLs was the same as having IMC/IR

Joking apart, safety in numbers OK but are you not pushing yourself in a corner?

Did the other person think the same and was there some 'egging on' in the most benign form with each thinking that we best not show that we are getting a bit uncomfortable here.

Just a thought.

:eek:

FD

[Aussie Andy]

G'day FD,Never realised that having 2 vanilla PPLs was the same as having IMC/IRNo... I don't think that 2xPPL = 1xIMC!

We were within VMC limitations, and I have flown in same conditions before, when I first got the license - but with hindsight and experience I now am much more cautious in these conditions. I'm not suggesting people should flex their personal minima too much, but just to take into account that better vis. etc. needed if on your own.

Perhaps you are not familiar with sharing legs with fellow-qualified PPLs, but a group of us fly fairly regularly together, and as far as "CRM" goes, we do decide which one flies, while the other navs, ahead of time on a per leg basis.

[FlyingForFun]

Nothing wrong with that at all, as far as I can see.

Personally, I'm quite happy flying in my local area in 5km vis, but I wouldn't want to go much further afield - the additional workload of navigation would probably be too much. On the other hand, if I have someone sat next to me who can concentrate on the navigation, and just give me headings to fly - or vice versa - then the workload for both of us is well within comfortable limits. I've never done this, but I'd have no problem doing it if the situation arose.

FFF
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