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Path: utzoo!mnetor!uunet!husc6!bbn!rochester!kodak!ektools!john
From: john@ektools.UUCP (John H. Hall)
Newsgroups: rec.aviation,sci.space,sci.space.shuttle
Subject: Re: SPICING UP AVIATION TERMINOLGY.....
Message-ID: <929@ektools.UUCP>
Date: Thu, 19-Nov-87 10:02:45 EST
Article-I.D.: ektools.929
Posted: Thu Nov 19 10:02:45 1987
Date-Received: Sat, 21-Nov-87 19:51:17 EST
References: <6812@ut-ngp.UUCP> <896@csun.UUCP>
Reply-To: john@ektools.UUCP (John H. Hall)
Organization: Eastman Kodak, Dept. 47, Rochester NY
Lines: 29
Keywords: ***PLEASE READ THIS*** IT INVOLVES YOU TOO ....
Xref: mnetor rec.aviation:5224 sci.space:3866 sci.space.shuttle:464

In article <896@csun.UUCP> abcscnuk@csun.UUCP (Naoto Kimura) writes:
>	    The rudder like one on a boat, is used to control direction
>	    (left/right or port/starboard).

The word "direction" has several meanings, only one of which deals
with the rudder.

1. Yaw, controlled by the rudder, is the angle between the
direction of flight and the direction in which the nose of the aircraft is
pointing.  Reference plane: the horizontal plane of the aircraft (like
the cockpit floor). In the unlikely occurence that an airplane were moving
"sideways" through the air, it would have a yaw of 90 degrees.
Usually we try to minimize yaw and so keep the pointy end of the
aircraft into the relative wind.

2. The direction of flight, or "heading", controlled primarily by the 
ailerons.  This is the compass direction the airplane makes relative
to the air in which it is flying.

3. The direction of the aircraft's ground track, or "course" relative
to the ground.  It will differ from the heading if there is any crosswind.

Sorry if this seems trivial to the old timers out there, but I
remember that I had a hard time getting it straight.  Er, I do
have it straight, don't I?-- 
John Hall, Supervisor: Software Tools Group, Software Engineering Laboratory
EASTMAN KODAK COMPANY, 901 Elmgrove Rd., Rochester, NY 14650,  716 726-9345
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