Honeywell KFC225 autopilot roll servo failure

Hello Peter,

The indications to me (I am an experienced h/w and s/w design
engineer) is that nobody has done any analysis on the failures, and
that the failed units are simply repaired and recycled into the
production process, or perhaps into "warranty exchange" units, as is
normal in the avionics business.

If they really did that they would be racking up a huge liability
portfolio. In the world of med electronics the FDA would pretty quickly
shut down everything from production to sales, followed by a "root
canal" type audit of the QC process.

If you have the impression that the problem hasn't percolated to upper
management you could help that process along by a letter to the CEO.
Sometimes that does wonders.

In avionics, one tends to get items which are often several years old,
when getting a warranty exchange unit. I've had a 10 year old KI229
RMI supplied in this way.

That may be ok if it's a full refurb like it is done on engines, IOW
where you get a zero-hours paper with it. But from an ethics point of
view they should tell you if it's a refurb.

I wonder if there is some kind of lemon law for those parts. If you buy
a car in California and repair attempts failed x many times you can
demand a full refund.

Other than that, could there be spikes caused by either the servo motors
or by some other gear that fry something?

Regards, Joerg

http://www.analogconsultants.com