Baro Alt

[flybrianfly]

It seems weird to me that barometric height (i.e. pressure altitude) is part of the navigation message. Typically the only data needed to compute and send barometric height would be the static pressure. I get that this is an estimated state, but so is indicated airspeed and true airspeed, which are grouped as separate messages in equipment/air_data.

I would argue that this is more important than just semantics. We have an air data computer CAN module, which has static and differential pressure transducers and an RTD front-end for an Outside Air Temperature (OAT) probe. I would expect our air data module to estimate and send the air data states (i.e. airspeeds and altitudes), but right now I have to either:

1. Send static pressure and expect baro alt to be computed elsewhere
2. Send the navigation message, which is huge, just to send the baro alt estimation

So, I propose that baro alt should be it's own message under equipment/air_data, just like the airspeed messages.