Given that AoA is still measured and used by the robot ... it is useful information, isn't it?
Surely AoA (and perhaps a GPS speed indication for good measure) would be very helpful in instances where airspeed indicators have gone doolally and the aircraft computers are assaulting with pilots with a bunch of not necessarily consistent error messages and alarms?
All modern aircraft rely on system redundancy, but can any system be deemed truly redundant if it relies on the same components on each of its legs? (I'm imagining that more than one pitot tube iced up). Given the problems of producing 'true' redundancy in a single measurement system, why not admit that visible workarounds should always be available to the
pilot?
With respect to observations of the sort listed in quotes simillar to the above, I have the following comments;
1. In my flight training some 60 plus years ago, I was tought to use
"needle, ball airspeed" as the absolute minimum to get out of
a sticky situation. On todays panels, I notice more than one attitude,
direction and speed instrument all of which driven from different sources
i.e. main batteries , stand-by battery, electric gyro, air vaccuum, pitot
pressure etc.
There was recurrent training in the use of this. The "ball" function is
also still on panels, so is a magnetic compass etc..
2. I have not seen much, if any, mention of "pitot heat" ,but that should
be one of the first actions of any crew member seeing airspeed
deterioration etc. It would be odd if all sensors were not being heated
at the same time. I burned my fingers (once only !) when checking a
pitot tube for wasp intrusion (one may remember this is very common
at certain times of the year).
3. What I suspect is the the sophistication used in designing an all
electronic/electric airplane caused programmers to assume pilots
are "managers" instead of "stick and rudder" chaps who can fly an
airplane by hand and who would prefer to receive an airplane that can be readily flown by hand, even under some type of adverse conditions, such as
turbulance. Methinks, these compromises in the interst of payloads and speed have left pilots to accept situations where they have precious little leaway of reacting, but, statistically, taking a relatively small risk.After all
we can all use a paycheque from time to time, no?
4. Anyone who read stories (Thud Ridge etc) about fighter pilots, most recently in in Vietnam, hearing multiple warning sounds in their cockpits made the conscious decisions to switch the f'rs OFF! The overload being considered more dangerous than flying out of harm's way and retain situational awareness.
5. GPS was listed as unreliable because only groundspeed is shown. That
is so, but the modern GPS reading can be corrected by a pilot knowing
the windspeed on his flight level, which at around 40,000 feet is fairly
directionally constant. In cu-nim systems this may be of not much use
because of the cloud's influence on its surroundingding air.
In gliding, GPS can measure the wind because when a glider circles
to climb, the drift is measurable and the wind speed become known
giving a read-out of both GPS ground and air speeds.
6. Perhaps certain cultural behaviour with certain flightcrews could mean
that crew members could be/feel intimidated by captains and fail to
throw out the book and do what is needed in an extraordinary situation?
KLM/Tennerife comes to mind.
I cannot judge the reactions, or the lack thereof, displayed by the flight
deck occupants on flight AF447, but if too much confusing information lead them to make errors of oversight/ignorance, then the obvious answer is to simplify the management in these situations, rather than have the computer sensors throw multiple warnings in the air and on the panel ! Perhaps computer programmers should bear this in mind and start refining the systems they concocted. My two cents.......
