Fog.

[JohnRayner]

Looked down from pretty clear blue skies (bit of haze, nothing crazy) to walk around the plane prior to my lesson (the first one in a good month I might add)

I looked up at the end of the walk around (five minutes, I swear) to see visibility already degraded to below minima, and my instructor shaking his head slowly...

ARSE!

[BackPacker]

That'll teach you! Five minutes walkarounds.... Tsss!

"Kick the tires, light the fires, first up is the leader."

[Pace]

John

Sorry about that as it must be very frustrating for you. Fog can creep up on you quickly. Not a major problem unless you loose your engine, want to get back into your airfield or do not have much fuel on board.

Fog can be a problem. I can remember flying at night into a field which was not manned. The lights were put on for me for a night approach. Flying over the airfield in the pitch dark I could see the lights clearly and set up an approach to land. Still no problems and continued the approach to land.

Went to flare and all of a sudden the screen went white. Touched down stopped and taxied back hardly able to see the runway in 200 meter fog 10 foot thick

Pace

[Foxy Loxy]

Fog can engulf a coastal aerodrome incredibly quickly.....

[JohnRayner]

Indeed!

I was happy to have my practical lesson in the rapidity of onset of fogging whilst on the ground. Much better than while on final, I'm sure!

"Kick the tires, light the fires, first up is the leader."

Heh. Like it!

Regards

JR

[AfricanEagle]

Where I live fog is almost unknown, just an occasional appearance a few times a year in the early morning.

Last month in the UK, a beautiful day, next to the aeroplane discussing about the flight to be. I turned my back on the clearly visible runway, picked up my bag, checked charts, turned around. The runway had disappeared, covered in fog. I couldn't believe it, it happened so suddenly. Scared me sh!teless.

[BackPacker]

The trick of course is to turn something like that into a lesson. Find out exactly what caused the fog. Was it due to radiation, lake effect or whatever?

Usually when fog rolls in rather quickly it's a local effect, only happening with a certain wind direction and speed, and with a certain water temperature / air temperature difference. Find somebody experienced with the local conditions, and let him/her explain what the conditions were that lead to the fog rolling in this quickly. Next time you'll be able to recognize those circumstances and can be extra weary.

[Gertrude the Wombat]

Turned up for a lesson, bright sunny day, infinite visibility, no hint of anything wrong with the weather.

Instructor said sorry mate, there's some fog coming, no flying today.

What a load of nonsense, I thought, and went to do the shopping instead. And half an hour later I couldn't see across the road whilst driving to the supermarket.

(There hadn't really been much indication of anything that dramatic being about to happen in the forecast, but the instructor had cheated ... couple of phone calls from mates at upwind airfields.)

[LateFinals]

I cancelled a flight a couple of years ago, fog was forecast en-route EGTR - EGJA, around compton / SAM if I recall, departure and arrival airports were fine. I thought it was not worth risking a possible engine failure over fog in a SEP. A flying friend of mine thought I was being over-cautious, what do others think ?

The phrase old pilots and bold pilots comes to mind ....

LF

[Lister Noble]

End of last year went for a local bimble in the Cub,forecast was good,but the vis gradually got worse so I returned to airfield which was not far away.
Turned downwind and as I was about to turn onto base almost lost the strip but could still just see it.
Now about 600' so turned onto base and could just see the mark to turn on final.
Turned on final and the strip was visible and then as I approached became clearer.
Landed all OK,but reminded me of the advice from one of my instructors .

"Never be fooled by the sucker's gap"

Well ,that is very good advice but it wasn't really a sucker's gap as the wx had bween fine,just a sudden unexpected deteriation in visibilty.
Certainly makes one think,what would I have done if it did clag over,all we have is a radio and very few basic instruments,anyway I'm not trained IMC?
Lister

[strake]

Well "there I was" at Coventry one February night in 1984, hacking round the circuit in a Beagle Pup putting in the touch and go's (or was it full stops, can't remember) to get my night rating.
I'd been aware that it was getting a tad misty as I took off for the last time but on downwind all was well. Imagine my surprise then, as I rolled off base onto finals, watching the runway and approach PAPI's disappear.
My finals call was something like "G-AP finals to land..er..is it possible to turn the lights up please?" Suddenly, out of the dark a streching rectangle of light appeared and down I touched. As I slowed the Pup, it felt like I was in a corridor of light and as I joined the taxiway, the lights returned to normal and I realised how much fog had descended in a very short time. Approaching the ramp area my instructor, Bill Burnhope, made a patting motion over his heart (sorry Bill). His final words that evening, were to tell me that Coventry would be billing me direct for the electricity.

[BackPacker]

Certainly makes one think,what would I have done if it did clag over,all we have is a radio and very few basic instruments,anyway I'm not trained IMC?

LN, as far as I know, if fog rolls in suddenly it's typically a very local effect and the fog layer is usually not that thick - maybe 100 feet at most. So you can usually divert above the fog layer to a fog-free airfield.

Obviously this is not true for fog under an inversion or related to a warm front. That sort of fog can cover large areas. But that type of fog typically doesn't appear in a matter of minutes, and is usually forecasted in any case.

Somebody with more experience in typical UK weather can comment further?

[Pace]

I flew a Citation from Bournemouth calling in at Bristol Filton. The landing into Filton was right on minima at Dusk with the whole of London going down fast.

I had to position to Southend which being by the coast was clear in this situation and forecast to stay clear.

A night takeoff from Filton in fog and regular updates on the Southend weather sounded good. I was handed over to Southend only to be told that one end of the runway was fog bound followed by the rest was down to 200 metres in the course of being 12 miles out and 5 miles out .

Biggin is higher up and was still clear so elected to divert there landed at Biggin with patches of fog on the runway.

Fuel is your friend so always take on much more than you need if in doubt. Do not rely on one alternative but have a number of potential plans as fog is very fickle.

With land bound fog often coastal fields remain clear and visa versa.

Fog can be extensive. On another trip I flew to Aberdeen. There was no glimpse of the ground the whole way up. The whole of the UK was in fog with only the tip of Scotland fog free.

Alternative was Ireland which was totally clear so be prepared to divert some way if you have to do the trip.
Localised fog can be very thin and near river or water or in low lying areas and maybe only 10 foot thick other fog can go into hundreds of feet thickness and cover an extensive area.

Pace

Pace

[IO540]

As Pace says, lots of fuel is the way to do this - as with any dubious weather. This kind of stuff is likely to be widespread.

[scooter boy]

Flying over fog

I did Plymouth to Leeds-Bradford a couple of months ago at night crossing over an almost completely foggy UK. I didn't see any ground lighting all the way from departure from Plymouth (which was clear) until 20 miles South of LBA.
LBA was CAVOK as it is up on the top of a hill.
Humberside (my origninal destination) was fogged out as was practically everywhere else.

Pace and IO540 are right about fuel, fill right up.

Prior to the flight get the TAFs abd METARs and know what the extent of the fog is likely to be. It is worth printing these out so you can refer to this info in flight.

En-route use your radio to listen to the ATIS of each airfield you pass, tune in to VOLMET and don't be afraid to ask for weather from ATC en-route, or if they're too busy call London info on box 2 and request it from them (just like the airlines do).

SB

[AfricanEagle]

En-route use your radio to listen to the ATIS

Very true and very useful.

On a recent flight tuned into Lyon ATIS some 20 minutes before arrival only to hear "check your minima", the place was completely fogged in.

Gave me time to replan and divert.

Aeroplane was then stuck at Dijon due fog and ice for 20 days but that is another story.

[BEagle]

Landed at Scampton once on a cold, damp winter morning. As we ran down the runway, the effect of the Vulcan's wing was to cause a sufficient mixing effect for the supercooled droplets just above the runway to turn into fog. We streamed the drag-bag and braked rapidly to a halt, then had to be led to dispersal by a fire wagon - we could hardly see a thing!

Got airborne at St Mawgan once, only to see what looked like smoke pouring in to the upwind end of the runway - it was thick sea fog! So I raced it downwind in my little Bulldog and threw the aeroplane on the ground a few moments before the place went out in fog.

But Brawdy was the worst place for 'supersonic stratus'...

[ShyTorque]

But Brawdy was the worst place for 'supersonic stratus'...

I agree, in 1977 (or was it 78?) I helped "bed in" the then newly installed Hawk simulators. We arrived and noticed the 40 kts of fog. Three weeks later, we left with the base still shrouded in 40 kts of fog. I had no real recollection of what the base looked like.