Organization: The World Public Access UNIX, Brookline, MA
References: <etxjema.714984523@kk270>
Distribution: rec
Date: Fri, 28 Aug 1992 13:48:40 GMT
Lines: 50
In article <etxjema.714984523@kk270> etxjema@kk270.ericsson.se (Mikael Andersson TT/RKE) writes:
>Hi everybody,
>here's a question that might be a FAQ:
>
>On the model that I've started to build I can choose between two landing gear types: trigear type (with nose wheel) or bigear type (no nosewheel).
>
>All my previous planes had trigear and that worked fine for me except on some bad grass fields where the prop hit the ground if you ran into a small hole.
>
>Now I'm thinking of trying a bigear to make the plane easier to run on the ground but what about start and landing?
>The start won't be any problem but what about the landing?
>
>Mikael Andersson
>Stockholm
>Sweden
>email: etxjema@kk.ericsson.se
As far as the physics is concerned, a trike (trigear) is easier to
handle on the ground than a taildragger (bigear). See "Stick and
Rudder". When a plane is rolling, and starts to veer off a straight
track it will tend to ground loop -- make the turn tighter and
tighter. This can be controlled directly with rudder or indirectly
with the resistance of the third wheel. In a trike the nose wheel is
heavy on the ground until you rotate (feed up elevator) while on a
taildragger the tail wheel is not as heavy on the ground and can be
overcome by the plane's tendency to ground loop.
Trikes will land easier "hot" (ie. fast ground speed) than a
taildragger. When a taildragger rests on the ground the wing's angle
of attack is high because it's tail is resting on the ground. When
the plane is comming in fast, the angle of attack is low so the mains
touch the ground first and the tail settles in later. If the tail
settles in too quickly, the increased angle of attack will generate
enough lift to get the plane airborne again. This accounts for the
"bounce" when you land a taildragger to hard. If you are really good
you can land a taildragger really fast by putting the mains gently on
the ground and then using down elevator to throw the tail up. The
force of the air over the tail will keep the plane from nosing over
until you are going slow enough to drop the tail. The easy way to
land a taildragger is to make a "three point" landing where the plane
is going slow enough that the tailwheel will touch the ground at the
same time as the mains. Of course in a trike the plane rests on the
ground with a nice low angle of attach so you can grease it in very
fast with very little bounce.
Because of the naturally high angle of attack, a taildragger will
leave the ground at a naturally slow speed with a short roll-out.
This is an advantage if you learn to properly handle the rudder to
