Andrew Sarangan wrote:
On May 28, 11:59 am, Luke Skywalker wrote:
On May 28, 8:11 am, Ron Natalie wrote:





Dan wrote:
On May 27, 5:44 pm, Mxsmanic wrote:
How do autopilots make coordinated turns even when they cannot control the
rudder?
If they don't control the rudder, they do not make coordinated turns!
--Dan
Boy we have the blind leading the blind here.
The whole point of that big vertical slab of metal sticking out of the
ass-end of your airplane is to provide a natural tendency for the
aircraft to fly coordinated. The pedals are just there for the
outlying conditions (low speed, high AOA for example) and fine
adjustment.
Ron...

oh my goodness...get some time with a good book on the subject and
then a CFI.

Robert- Hide quoted text -



Ron is correct. The vertical fin makes the airplane weather-vane into
the wind, and that's what co-ordination is all about. The rudder is
there only to help the vertical stab do this job.

A perfect airplane will not need rudder.

Not true. The vertical fin can only provide a weather-vane affect when
a slip or skid has been induced. In coordinated flight there is no slip
or skid and hence the fin provides no lateral force. When you begin a
turn, most airplanes will induce adverse yaw and the rudder can counter
than before a skid occurs. The fixed fin can only act once an
uncoordinated condition has been induced. Sure, it does mitigate the
skid or slip, but it absolutely can't prevent it as it can't provide a
force until uncoordinated flight is already established. The rudder can
do this and is why it is included.

The rudder isn't there to help the vertical stab do its job, it is there
to do a job that the vertical stab can't do.


Matt