Re: Yaw Damping was: An-124 and wing dihedral

Date:         16 Jun 98 02:15:26 
From:         Chuck <CHorning@MSN.com>
Organization: Delta Air Lines
References:   1 2
Followups:    1
Next article
View raw article
  or MIME structure

Jim Wolper wrote:
> Pete Mellor wrote:
>
> > [...] Dutch roll is
> > a vice of any delta-winged aircraft. Presumably, automatic
> > yaw-damping was achieved in pre-FBW days by a simple
> > analogue system (possibly part of the autopilot)?
> >
> > I'm guessing. Does anyone have any definite information?
>
> Yaw damping can be achieved using analogue output
> feedback and is usually included as part of an autopilot
> installation.  It is useful in straight-wing aircraft as well,
> especially those that fly at higher altitudes where the thin
> air may reduce the effectiveness of the vertical tail in
> damping yaw.

I would add to Jim's comment that while yaw damp is concidered part of
the autopilot system it works independantly of the autopilot.  The A/P
does not have to be engaged for yaw damp to work.

Also when the Y/D system moves the rudder there is no feedback to the
rudder pedals in the cockpit.

Chuck