Re: Snow on wings

From: (Jean Ludovicy)
Organization: EUnet Belgium, Leuven, Belgium
Date:         02 Jun 96 23:01:51 
References:   1
View raw article
  or MIME structure (W. Hodgins) wrote:

>Some time ago I was a passenger on a DC-9 flight out of Toronto in
>January as I recall. Looking out the window, I noticed a fair amount
>of snow on the was not removed and the aircraft took off
>with snow blowing off the wings as speed increased.
>I used to fly light aircraft in the early 70's and if I recall
>correctly we were supposed to ensure that nothing, not even frost,
>should be allowed to accumulate on the wings.
>What is the criteria for large an accumulation of light snow
>normally acceptable ?

Normaly no ice or snow may be tolerated on any aircraft wings.
Now in practice, if it is very cold outside and the snow is pure
pouder, in small amounts, which doesn't  stick to the surface ,
it will be blown of the wings  as soon as the airspeed  rises.
This is safer than to use antiice fluid with short overhaul times
when new snow is accumulating during taxi time which than may freeze
on to the wing surface.
In the case of your flight, it might have been this situation.
Anyway, it had been decided like that by the captain of your flight.
It was him who had all the information to make the right decision.
We may on speculate.

Fidonet:Jean Ludovicy 2:291/712.300