Dave:
Lord, had I only knew! Your explanation of 'PID' controllers was
specific and complete enough for my tired brain to acquire. It may easily
have been my fault that the NavAid device became entangled with controllers.
I would also like to think I would have worked it out in time - yeah.
I began commercial flying on DC-3s and the controller was me or
him. Then North Stars (DC-4M) derivatives which had an altitude capture
which would not have been accurate enough to maintain my licence. Up through
SuperConnies, Viscounts, Vanguards the "elders" (usually engineers who had
to be driven home at night) began to insist on the use of the autopilot
because of its great accuracy and dependability. THAT attitude was shot down
less and less until we have the brilliant brutes of today.
I always marvelled at the ingenuity involved and as they got
younger and I got older, the ability to figure out 'how' became an exercise
in futility. I must tell you that the firm didn't help. First of all,
because we had 'inquisitive' aviators who began to experiment (not me) and
because the opportunity for harm increased millionfold, companies began to
teach the workings of aircraft less on 'how the system works' than on 'how
to work the system'. This gave rise to "PFM" - pure ______ magic - as an
explanation of a device, and WHOGAS -
who gives a ____ - as an answer to a probing question. This solved the
instructor's problem (he didn't GAS), but it set an atmosphere of distrust
in both directions. "why do you ask?" and "how do you know?" became memory
items. I guess you'd say proof of my statement rests with the number of
'ignorant' Airbus incidents where maker don't tell all.
Had my outfit done what you just did, I would have been less
distrustful of the bumph we had to digest and probably turned out to be a
nice person. As it is, well, you know.
Anyway, a zillion thanks and happy Landings
Ferg
----- Original Message -----
From: Dave DeFord <davedeford@home.com>
Subject: Re: altitude oscillations
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