Re: Fuselage temps, wind, et al

From:         inet@intellisys.net (brian whatcott)
Organization: Telepath
Date:         12 Oct 96 22:13:09 
References:   1
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I'll take a shot at Ted's questions:

In article <airliners.1996.1894@ohare.Chicago.COM>, ntphil@ibm.net
says...
>
>Why is anti-ice applied on the leading edge of the wing (of a
>high-altitude) and not on the fuselage?

-because loss of lift is a more prompt performance deficit than
increase in weight.

>Can we assume that friction
>also generates enough heat to prevent a build-up of ice on the
>fuselage?

-yes, for supersonic types.

>And if so, what is the surface temperature of the fuselage at
>cruising speed/altitude?

For modest sub-sonic speeds, similar to the outside air temp.
The Standard atmosphere model assumes this decays from a sea level
value of 15 degC by abt 2 degC per thousand feet to 36000 ft where it
stabilizes at -56degC

Temperature rises at higher altitudes. In near Earth space, a spun
object may stabilize around 15 degC

Ice is only a hazard where much water is available in the atmosphere.
Hence the climb and descent phase is the principal risk.

>Without or without computers, how is wind & direction computed during
>flight?

Direction is indicated by magnetic compass or INS Loran GPS ADF VOR
etc...

Wind is inferred from differences between true airspeed and
groundspeed.

>Thanks,

You're welcome
brian whatcott <inet@intellisys.net>