Autopilot certification

"pitch accelerometer" is a nice word for a crude mechanism. It's a spring with a weight and it bounces from one side of the cage to the other making electrical contact. Opening the S-TEC "computer" and seeing how it is implemented was one of the biggest disappointments...

You are joking!!!!

Honeywell use the ADXL05. It has been obsolete for some time which may be one reason why Honeywell don't want to pick up the KFC225 project again. They probably do not have any electronics design expertise at Olathe nowadays. The replacement is the ADXL321 which is also going obsolete...

Avidyne's approach of certifying various glass cockpits as roll/pitch source for the DFC90 is very smart and so is the use of existing S-TEC servos (although S-TEC are trying to sabotage that but upgrading existing S-TEC installations, it's a good solution).

I am sure Avidyne used later technology...

What incidentally does amaze me is that nobody is using brushless motors. It's such an obvious thing. Anybody here into model planes? The STEC servos are 100% sure to pack up, and when they do, replacement is quite complicated because the bridle cable needs to be removed, replaced, and retensioned.

Avidyne were recently heard talking about dropping the STEC servos (probably partly because as you say STEC have sabotaged that option commercially) and are going to develop King-compatible servos.

But all of these use brush motors, with the King servos using brush motors of particularly low quality (from Globe, USA).

I would bet the same goes for the GFC700 but nobody I know actually knows. I haven't got my hands on the MM for those yet In fact MMs are almost impossible to find for any Garmin gear. The GNS430 MM has only just escaped into the wild, 14 years later (although the site I found it on has been rapidly taken down). A load of IMs are out, however.