Re: Fuselage temps, wind, et al

From:         Dan Auslander <dauslan@bgnet.bgsu.edu>
Organization: Bowling Green State University
Date:         17 Sep 96 13:53:07 
References:   1
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Newtimes Ltd. Philippines wrote:
>
> Why is anti-ice applied on the leading edge of the wing (of a
> high-altitude) and not on the fuselage?  Can we assume that friction
> also generates enough heat to prevent a build-up of ice on the
> fuselage?  And if so, what is the surface temperature of the fuselage at
> cruising speed/altitude?
>
Anti-icing is applied to areas of the airframe where it is needed.  Ice
accumulation occurs when supercooled droplets of water in clouds strike
the (colder than freezing temperature) airframe, and freeze
immeadiately.

This occurs most readily on leading edges of relatively small radius,
such as a wing, horizontal stabilizer, prop spinner, or pitot tube
(hence mandatory pitot heat on all airliners).  When air flows over
these surfaces, the relative wind (airflow caused by the moving plane)
must turn or dispalce rapidly in order for the airframe to pass through
the air.  The water droplets, however, cannot displace as quickly due to
their mass, and strike the airframe, forming ice.

--
Dan Auslander
Commercial Pilot, ASMEL-IA   C-182 N3292S
Email:  dauslan@bgnet.bgsu.edu
WWW: http://pizza.bgsu.edu/~dauslan/main.htm