the electronics boards strapped to the outside of the model, maybe only
protected by heatshrink, or similar.
When you use high precision measurements for GPS, IMU and air pressure, I
think you will suffer very badly from temperature and temp gradient
effects on those boards.
We got caught with this in evaluating a GPS board. We put the bare
board on a bench out in the open, and logged the position and velocity.
Both drifted badly, about 20 times worse than the published data, and
lead us to a long argument with the manufacturer until we ( somewhat by
accident ) shielded the board from air drifts. The drift dropped
immediately to an acceptable level. Yes I know GPS is all 'digital',
but in fact there is a very critical component, the TXCO oscillator,
which must remain exquisitely stable for the system to work, and temp
drifts over a few seconds were badly upsetting it.
Precision analog components like gyros, accelerometers and pressure
sensors will also suffer from these effects. Think about what happens
as you fly a model through air currents, thermals, etc, all at different
It would not surprise me if some of the bad GPS and IMU data I see
reported are due to the same problems, especially on those bare boards.
My recommendation would be to put all boards in an aluminum box ( even
foil would help ), and then put that in an insulating container or foam
wrap. This would cut down the rate of temperature change, and probably more
important, the temperature gradient, across those sensitive components.