Engine-out protection on the 777

From:         rdd@netcom.com (Robert Dorsett)
Date:         08 Jul 95 15:01:53 
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AvLeak has been running an interesting series of letters to the editor
regarding United's unusual-attitudes training.

The curriculum apparently calls for the practice of rolling wings level
following an engine failure after but near V1.  This flies in the face of
the technique most private pilots learn, which is to use the rudder to
correct the yaw.

A pilot pointed this out, and was firmly chastised--by other pilots, who
identified themselves as "jet" pilots--as not knowing what he was talking
about, aerodynamically, and from the perspective that it's more important
to maintain directional control, since one does not have a whole lot of
protected airspace to deal with at that point.

I note, however, that the 777 offers something called TAC, or Thrust
Asymmetry Compensation, which, according to Boeing _Airliner_, states:
"TAC counters the airplane yaw caused by an engine failure or throttle
split by providing an automatic rudder input during both manual and autopilot
flight."

So which is it to be?  Surely there's a correct aerodynamic answer, which
can transcend the usual bickerings of my-instructor-was-smarter-than-your-
instructor.




--
Robert Dorsett                         Moderator, sci.aeronautics.simulation
rdd@netcom.com                         aero-simulation@wilbur.pr.erau.edu
                                       ftp://wilbur.pr.erau.edu/pub/av