Brrrr - it's cold! Any tips for winter flying?

[Slopey]

Hi All,

It's a beautiful day up in Aberdeen - except I've got a stinker of a cold so no flying for me. However, I'd like some advice on flying in cold weather as it's not something I've done much of (given the mild year so far) - this is in a C172 with no de-icing of any sort.

The METAR for EGPD earlier today was along the lines of

EGPD 191030Z 22005KT CAVOK M01/M02 Q1033 NOSIG

The the F214 gives

10 350 10 -07
05 VRB 05 +02
02 280 15 +03
01 270 10 +04


Now, with it being M01 on the airfield, I'd imagine the plane to be covered in the same hard frost my car is which would be a nightmare to remove, so it's absolutely a no go.

However, as it warms up a little during the day and the sun melts the frost off (it's now EGPD 191150Z 26006KT CAVOK 03/01 Q1033 NOSIG), would it be safe to fly in the <6 degrees temperatures?

Ever mindfull of icing of any sort, with no clouds in the sky, would you expect to encounter ice in those sort of conditions? (I must admit although I can remember the types of icing and the dangers I'm not au fait with under the conditions they could form).

And with the F214: 0 degrees would be presumably above 5000 ft (which I would'nt go near on a quick bimble), but as the airframe pops through the air at 100kts, I'd imagine the windchill even at 3/4 OAT would mean icing was quite likely to form if there was enough humidity - but how do you know if that's the case? (or is there a rule of thumb or some other meterology concerning the humidity etc).

If anyone has any advice, I'd appriciate it - I'm not likely to head up in these temperatures - but I asked myself what I might expect in such conditions and I must say I don't know. (although I've not had a chance to dig out the Thom and look it up).

Cheers,
S.

[wbryce]

Take a pair of gloves for pre-flight!!

Last winter I arrived to find my stead covered in ice! It took me 2 hours to de-ice and I never did get to fly because my fingers took a further hour to recover and the next booking arrived with appreciation!!!! people are still laughing in the club room to this day.

[mm_flynn]

Key Tips,

Really cold and you may need/want preheat on the engine to minimise engine wear and have an easier start.

Having a friend let you park in their hanger (for even a couple of hours) makes the whole thing more pleasant.

Wear fuel proof gloves, its freezing if you spill on your fingers!

Ice in flight really only forms in visible moisture (clouds or freezing rain) when below 0. It can also happen on decent from warm air into below 0 clouds.

Removing frost is a MUST!!! and a warm garden spray can of aircraft deice like Kilfrost RD makes it easy, using your credit card or Halfords Deice and you will look a wreck just like your paint!

Because of the air density, aircraft performance is much improved.

Last, wind chill is about the improved heat transfer due to airflow - not relevant to icing, however, a different speed related issue is - frictional heating of the air will cause the temperature of the air to increase slightly (so your temperature probe will over read relative to the still air temperature).

[vancouv]

Slightly off topic, but as I was scraping the ice off my car the other day I was wondering where the visible moisture was that had caused it? The sky was clear, no clouds, no fog, but still ice formed on the car.

Surely when flying in sub-zero temps the same could happen on a plane, even if you don't fly into cloud? What am I missing?

[Mark 1]

The ice on you get on your car or aeroplane when it's parked outside at night is due to the surfaces radiating away their heat and being colder than the surrounding air. Moisture precipitates out of the air on the surface and freezes.
If you are moving through the air the aircraft will eventually get to the same temperarure as the air, so ice will not form.

That said, I have had clear air icing while flying in the circuit - probably due to the different air temperatures at different altitudes, and a cold-soaked aeroplane moving through warmer, moister air. It generally will melt again quickly and isn't usually dangerous.

Another thing to watch out for, especially on grass fields, is mud.
It can get into your flap and aileron gaps and inside the spats while taxying and then freeze at higher altitudes while flying.
I've had an air-brake on a Jodel freeze solid because of that. Jammed ailerons or elevators could be much more serious.

[unfazed]

Top tip

Move the aircraft so that the wings are facing the Sun then go and have a coffee and finalise your plan....when you come out the sun has hopefully defrosted your aircraft for you

If no sun stay in the warm and order a Full English !

[SkyHawk-N]

Never take an aeroplane out of a hangar on a cold morning, even if there is only a slight frost, and wash offending owl poop off of it just before a flight! :=

[niknak]

Yesterday I was travelling through Kings Lynn and I noticed a open cockpit microlight having a whale of a time enjoying the sunset.
My car temp' indicator said the surface temperature was -03 deg C, so I can only guess it was around that or lower where the pilot was, bloody freezing but a spectacular view!!!:D

[TotalBeginner]

frictional heating of the air will cause the temperature of the air to increase slightly (so your temperature probe will over read relative to the still air temperature).

Wow, I never knew that.

I know that on some airliners anti icing is used based on the total air temperature (sum of the OAT and skin heating due to friction). But I guess this is almost negligible on light aircraft due to their relatively low airspeed.

I had no idea that the surrounding air is actually warmed, especially as it's only in contact with the airframe for a fraction of a second!

[RatherBeFlying]

I found that scraping the frost between the rivet lines on a C-172 leaves quite a bit to be desired in performance:uhoh: so, took to carrying around extra windshield washer.

The automotive product seems safe for painted surfaces, but do keep away from the plexiglass as the alcohol is not good for it.

If the frost comes back on after removal, fly another day.

[IO540]

One needs one of those big plastic jerrycan type things with a push-down pump thingy in the top, used for spraying weed-killer etc. Cheap from DIY shops.

Fill it with slightly warm water. Avoid spraying warm water over frozen plastic windows though; they can crack.

Or, if the OAT is still well below zero, with de-icing fluid but then it has to be the right sort which is non-corrosive. That stuff (e.g. Aeroshell 07) is very expensive.

[Pitts2112]

I learned to fly in Illinois, mostly in winter, and, due to work, usually had an 0700 report time to preflight.

We used a big stiff-bristle broom, like one for pavement, to get the frost off. Worked like a champ and never worried about it building back up again as long as there was no visible moisture in the air.

We pre-heated, too, but only because it got a bit colder than M01 and because we could.

Other than that, long underwear (Icebreaker merino wool from NZ, can't beat it!) and get the engine warmed up before takeoff, it's ops normal.

Pitts2112