CaptSensible

No doubt you've seen it. You fly for three or four hours at high altitude through European winter skies, arrive at Med type destination (at night). Fuel is pumped into very cold wing, mixing with very cold inbound fuel. The wing skin temp is sub-zero, and ice starts to form at the wing root.
So you ask the local dispatcher/engineer to bring on the de-icing gear, and he looks at you with wide eyes and says, "Que??"

Can some of you regulars on the charter ops let us know what the secret is? How do you get the bugger de-iced?

Bullethead

Cap'n,
From our, B747-400, ops manual;

Exterior safety Inspection.

Surface.................................Check
Takeoff with light coatings of frost, up to 3mm in thickness on lower wing surfaces due to cold fuel, is permissible; however all leading edge devices, all control surfaces, and upper wing surfaces must be free of snow and ice."

Hope this helps.

static

Sensible,
I know what you mean, we try not to land with more than 5000 kgs of fuel, so the fuel will not touch the upper surface of the wings.(737 300/400)
If ice does form on the upper surface, de-icing is necessary, and what is really neat is an engineer with a small hand-pump with de-icing fluid. (like what you use for weed-killers) That way you can easily remove the small amount of frost on top without the whole de-icing treatment (often not available anyway)

Good luck

Nightstop

Another trick if you've got good ground engineering support is to transfer the cold wing fuel from the mains into the centre tank then fill the main tanks with "warm" fuel.

411A

Hey there Capt'n, you must tanker a lot of extra fuel, "Que?'

gaga1976

Or you wait for sun to come up. We did in CMN

CaptSensible

411A, Nope, we weren't tankering. In fact we were not far off legal alternate fuel on arrival last time I saw this happen....couldn't get any significant extra on before departure, too heavy.

Anybody tried using a sweeping brush to remove the build up? At least you can get the deposits down to the 3mm allowed!