Of some interest is the Document by Boeing circa year 2000 that suggested an AOA indicator in the pfd would be of assistance when airspeed went bonkers, etc see pages 19-20
of course such a display was/is optional at a no doubt ridiculous cost -
and nothing was said that in case of ANY disagreement with pilot- HAL rules unless you quickly pull his plug
With the nonnormalized design, the
position of the needle is a function
only of sensed AOA. The red tick mark
for stall warning may behave erratically
in a pitot or static failure state, as may
stick shaker, PLI, and speed tape amber
and red bands. However, the AOA
needle and digits will remain stable,
and the indicator itself still will be
Improved situational awareness and
flight crew training.There is a desire
to use AOA information to increase
the flight crew’s understanding of the
physics of flight and their general
awareness of the state of the wing dur-
ing normal and nonnormal conditions.
Within certain limitations, the display
provides this indication in a clear,
unambiguous format. The degree to
which AOA can be used to increase
knowledge and airmanship depends, of
course, on the approach taken by the
airline in training its flight crews and
the use of the indicator in training sce-
narios for nonnormal procedures. Some
of the limitations are discussed below.
Pitot or static system failure
requires the flight crew to take several
fundamental steps to resolve the
problem (see “Erroneous Flight
Instrument Information,” Aerono. 8,
Oct. 1999):
Recognize an unusual or suspect
indication.
Keep control of the airplane
with basic pitch and power skills.
Take inventory of reliable
information.
Find or maintain favorable
flying conditions.
Get assistance from others.
useful as a backup for unreliable
airspeed,provided the AOA
vanes are undamaged.
A variety of potential uses for
AOA were examined during the
design of the new AOA indicator:
Improved situational
awareness and flight crew
training.
AOA backup indication
following pitot or static
system failures.
Reference during upset
recovery, windshear
escape, and terrain
avoidance maneuvers.
pages 19-20
And earlier page 12 explains proposed use on boeing models
A dedicated AOA indicator shown
on the primary flight display (PFD)
recently has been developed in
cooperation with airline customers.
The new indicator is offered as an
option on the 737-600/-700/-800/
-900, 767-400, and 777 at this time.
During the development of the
new indicator, discussions with
airlines, the NTSB, and U.S. Federal
Aviation Administration (FAA) pilots
and engineers provided a unique
opportunity to examine potential uses
of AOA and the many existing
uses that have evolved in recent
decades along with advances in
display and indication technology.
This article discusses the following:
1.Basic principles of AOA.Angle of attack
2.Airplane performance and AOA.
3.AOA measurement.
4.AOA indications and flight crewFlight path angle
procedures in current Boeing
production models.
5.Design and uses of a separate
AOA indicator.
http://www.boeing.com/commercial/aer...ero_12/aoa.pdf