Turn coordinators are the simplest of gyros, since the gyro mechanism
spins in one plane, operating a very simple visual cue mechanism. So,
they're pretty rugged, but the motors do fail, or get noisy (electrically and
audibly) over time, and an overhauled gyro may or may not have a new motor.
Given the price differential, a new one I think is smarter, and for VFR I
wouldn't buy a fancy one.
For IFR, it is required, as a backup and cross-check of the AI. For VFR, it
(in lieu of an ASI) serves only as a rather poor safety mechanism in the
event of sudden IMC (especially for night flying). On that basis, a turn
coordinator is preferable to the old turn/slip indicators. Since the gyro
mechanism is canted a bit from vertical, it reacts somewhat to bank only. So,
for VFR you can easier keep the wings reasonably level if you blunder into,
and hopefully out of. IMC. If that is the purpose in having one, I don't
think a remote switch is a good idea. In poor weather, one may not have the
presence of mind to make sure it is turned on, when sudden IMC is
encountered.
Regards,
Fred Fillinger, A063
In a message dated 11/24/99, JohnJMoran@aol.com writes:
> How does one select an electric turn coordinator? The prices seem to vary
by
> 50% or so for what look to the casual observer to be identical units. In
my
> VFR Europa this will be the only gyro.
>
> EGC, IFR, RCA, Wultrad (ACS lowest price unit) ?? Surely, some are more
> reliable than others, but how does one tell? Based on a discussion with a
> maintenance tech, brush failure seems to be the most common failure
followed
> by bearings -- any other common problems? Do weight and size vary much?
> Also read somewhere that there is a brushless unit which uses an AC motor
> plus an internal inverter, but who makes it? Is it more reliable?
>
> A friend suggests adding a switch to allow removing power from the TC
during
> severe clear weather. Is this reasonable, or will it likely be powered
down
> just when needed? Would this prolong its life or is airframe vibration
the
> failure inducer?
>
> John A044
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