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Flying VFR in Haze - remaining legal.

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Flying VFR in Haze - remaining legal.

Old 29th Aug 2017, 12:21
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Flying VFR in Haze - remaining legal.

I am still broadening my flying horizon/experience so some of this may be second nature to some experienced VFR pilots.. but I have questions that pop into my head which I wanted to get a bit of clarity on.

I flew yesterday and it was:

1) Hot and Sun in front.
2) Hazy

..and according to my assessment with my 'eyes' I thought the viz was around 5k.

Pre-flight planing for a flight in the South East to route via Brighton Marina, Solent and IOW.... All the METARS/TAFS didn't report Haze - which I know according to the definition to be 'dust particules trapped in the air' and smog also trapped below the cloud base which was reported as few at 4,500 feet.

Little or no Wind to disperse said Haze or SMOG.

Assessing horizontal viz with your 'eyes' (in my book) may not be easy to a new-ish pilot? so what I think could be 5000 meters - may be 3000 meters to other pilots - which puts a VFR flight out of minima and potentially 'illegal' according to the rules of the air - depending on airspeed, level etc?

Taking off I noticed it was quite 'hazy' and the sun in my eyes - ground still visible on the surface and London TMA above - so <2,500ft is the only option until near the coast when you can climb to above.

What options do you have when it is really hazy, sunny without the fear of getting trapped in IMC? Do you climb above without really know how far the haze layer is (typical book figures give 100-200ft)?

If you land somewhere in the 'haze' and you are asked for a license do you lose it for flying in said Haze??

(Didn't happen - but I am trying to establish boundaries or 'go or no-go' decision points on the ground from paperwork and flight planning instead of 'going up' etc)

I have attached some pictures taken around the S.E by a PAX - different stages of flight.

Picture 1
Picture 2
Picture 3
Picture 4
Picture 5
Picture 6
Picture 7
Picture 8


It was busy yesterday and other aircraft were also flying which leads me to believe the viz was okay.

I don't want to 'lose' my license for flying below minima but unless I experience it the first time - I won't know what the second time weather phenomena will look like.. or have any sort of plan to deal with it?

Curious.

Scoobster
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Old 29th Aug 2017, 12:28
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Assessing horizontal viz with your 'eyes' (in my book) may not be easy to a new-ish pilot?
One trick that was taught in the mil on occasions was to use timing...5000 metres is roughly 3 miles...which at (say, for example) 90 knots ground speed is 2 minutes flying time. So if a ground feature on track pops into view and you overfly it in less than 2 min the vis is less than 5 km.

Adjust figures above as appropriate for your type and speeds, and yes, it is only a rough and ready method.
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Old 29th Aug 2017, 12:30
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VFR means just that and if your visibility is reduced to less than the minimum at any time for any reason e.g. flying into the sun or haze, then you are not in VFR conditions.
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Old 29th Aug 2017, 12:52
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Originally Posted by funfly
VFR means just that and if your visibility is reduced to less than the minimum at any time for any reason e.g. flying into the sun or haze, then you are not in VFR conditions.
I know what it means.. The thread title could have been better worded agreed but the content is what Im trying to get answers on.

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Old 29th Aug 2017, 14:31
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Flying into sun on a hazy day vis not good and not vfr, then IMC, flying downsun in haze vis more than OK, VFR.

This is a black/white question. You are either VFR or not. Is it still not the visibility ahead from the "flight deck" that will determine your conditions?
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Old 29th Aug 2017, 14:34
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The pictures don't look out of the ordinary. I prefer to fly above the haze layer, which round my way is often around 4,000'.

You can be what as far as I can tell is legal VFR with what nonetheless feels like zero visibility into the sun. Which makes navigation just using map and compass "interesting", as you can see where you are, and you can see where you've been, but you can't see where you're going.
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Old 29th Aug 2017, 14:36
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(Didn't happen - but I am trying to establish boundaries or 'go or no-go' decision points on the ground from paperwork and flight planning instead of 'going up' etc
If TAFs > limits go, if not don't.

If vis deteriorates when up there and METARS in vicinity say vis = legal, land if you are not happy, continue if you are. If vis on arrival at destination is below limits divert to somewhere else, getting help on Metars from ATC if necessary.

None of those photos look like anything approaching minimum vis to me.
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Old 29th Aug 2017, 14:45
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I think I should provide some more input..

If you are on the ground (pre-flight planning) and the sky looks blue and clear, high cloud and sun shining. You check the METARS and TAFS..

The reports come back as 'XXxx 281000Z 24006KT CAVOK 27/15 Q1011'

TAF comes in at something like ' XXXX ... 26007KT 9999 FEW 045 BECMG 2817/28/20 01010KT

Haze doesn't get reported in a METAR (I believe).. Mist ('BR') does hence in this case it is clear cut you wouldn't go up because it is not legal.

On the ground, you only have these METAR/TAF reports and a few other sources like Rain Radar, Weather Online, XC Weather etc.. to go by to make a 'go or no go decision' - until you get into the SKY... and then it turns out to be Hazy - as was the case on my Skills Test under the Examiners License! Going back a a short while ago!

What do you do - if you are below minimums I agree it is illegal. Once should in theory turn back and land.. I don't know if PPL without IMC rating or CPL without IR actually turn back or not?

But if you believe according to your 'eyes' that the vis is 5km and you are legal and it is just 'hazy' - what actions are helpful to conduct to make it a safer flight? Climb, Descend etc

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Old 29th Aug 2017, 14:47
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Originally Posted by Mariner9
If TAFs > limits go, if not don't.

If vis deteriorates when up there and METARS in vicinity say vis = legal, land if you are not happy, continue if you are. If vis on arrival at destination is below limits divert to somewhere else, getting help on Metars from ATC if necessary.

None of those photos look like anything approaching minimum vis to me.
I agree with the above -I haven't been in the sky when it has been 'minimum viz' so I guess I don't have anything else to compare against.

Does it look hazy at all in the pics?

I was just concerned that I might not have been legal that's all.

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Old 29th Aug 2017, 15:20
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Are you travelling in the daytime at less than 140kt in class G and in sight of the surface?

I thought the lower limit under these circumstances is 1.5km in the UK.

(Though personally I'd be looking for somewhere to land pdq)
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Old 29th Aug 2017, 15:21
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Looking at your pictures, I would not think you have anything to worry about re. VFR conditions but if you feel out of your comfort zone then better to be on the ground wishing you were up there than.............etc.
Good luck by the way with your flying, if you have your PPL then getting instrument trained is your next step. I suggest that you will find this the most interesting flight training you can get.
FF
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Old 29th Aug 2017, 15:25
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The pictures show pretty good viz - you even had a distinct horizon. Seriously hazy is when you can only see straight down.
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Old 29th Aug 2017, 15:25
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Looking at the pictures you can see the horizon which is considerably more than 5km away.
5km is in reality pretty poor vis and unless you really needed to go somewhere I suspect you would,not even walk out to the aeroplane.
Imagine a typical large airport runway of 8000ft, picture yourself on a visual base leg, the far end of the runway is about 5km away. Would you fly in that visibility?
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Old 29th Aug 2017, 15:26
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Originally Posted by funfly
Looking at your pictures, I would not think you have anything to worry about re. VFR conditions but if you feel out of your comfort zone then better to be on the ground wishing you were up there than.............etc.
Good luck by the way with your flying, if you have your PPL then getting instrument trained is your next step. I suggest that you will find this the most interesting flight training you can get.
FF
Thank You..

Not out of my comfort zone and it was a good, safe flight, and interesting - I was just trying to get a mental picture of what minimum visibility would look like compared to the visibility in the pictures.

My eyes 'felt like it was >5km' and perfectly legal but I wonder what <5km feels like. When you don't know something.. you always can't help but wonder!

Thanks!

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Old 29th Aug 2017, 15:28
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As for legality, there is no one up there measuring in-flight vis in the open FIR so worry not.

Getting clearance into/from an aerodrome within class D is another matter though.
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Old 29th Aug 2017, 15:32
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Originally Posted by bingofuel
Looking at the pictures you can see the horizon which is considerably more than 5km away.
5km is in reality pretty poor vis and unless you really needed to go somewhere I suspect you would,not even walk out to the aeroplane.
Imagine a typical large airport runway of 8000ft, picture yourself on a visual base leg, the far end of the runway is about 5km away. Would you fly in that visibility?
Ah that's what I was looking for.. some kind of 'mental model' as to what 5km of visibility would actually look like for my brain to process.

If that's only how far I could see I would definitely not fly.. My home base is only 3500ft runway and if I couldn't make the far end of that out then I would be concerned.

I hear a lot of stories about licenses being revoked etc for pilot stupidity and what could have been avoided.. though I don't know how true!

Thanks!
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Old 29th Aug 2017, 15:36
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The visibility in the photos seems OK to me.
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Old 29th Aug 2017, 16:30
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My home base is only 3500ft runway
Gosh! Heaps in a PA28! That's around 1,000 metres in real terms. I don't know where you're based but I seriously suggest that you go with an instructor to a more limiting aerodrome, perhaps with about 600 metres and get proficient there.

Also, as others have said, that's a pretty decent horizon in many of those pictures. Unfortunately, a beautiful blue sky when viewed from the ground when there's high pressure usually means a less than gin-clear view aloft, but it looks like you had very good conditions for your flight.

TOO.
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Old 29th Aug 2017, 16:54
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It can be difficult to decide the level of visibility if you are in a flat area, there are no hills to act as markers, in your photos the viz is fine. As you gain experience you will take off in poor visibility, sometimes so bad that at 2000 ft you can only see straight down, it is easy to get disorientated and lost so do a circuit and land back. You do need to learn how to handle unexpected conditions during a flight, wether to turn back, detour or land away
Landing into a low sun even in quite good conditions can be tricky, again with practice you will become confident, if you are having routine check flights take a good instructor with you in marginal conditions you will pick up a lot of tips
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Old 29th Aug 2017, 17:03
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Originally Posted by Scoobster
I wonder what <5km feels like
Being told to orbit on the downwind leg and then needing to use instruments to find the airfield again ...
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