Quote Originally Posted by Airmutt View Post
But Ron there are electronic devices ( smart watches, phones, tablets) that can sense pressure altitude. I also have a pic of a Volksplane that has an automotive style altimeter installed. I can set baro on my watch and get pressure altitude too. Do those qualify as an altimeter? Setting the requirement discussion aside, where does it state it has to be a static system driven device. And that is really the crux of my question.
(for altitude only) No one said that there had to be a conventional static system (static port(s) on the side of the fuselage, on a wing probe, etc.). So, yes, your pressure devices mentioned above (watch, iPad, automotive unit, etc., IF baro adjustable) work, and IF … per the regulations (for certified aircraft) the unit meets the TSO for altimeters (static pressure in -->correct altitude) AND the static system (in your case the cockpit environment and the watch) must be calibratable to +/- 30' per 100 knots (airspeed).

I'll address airspeed in my next reply (to get your quote on that topic).