Brief Description: Zero p IAS.AOA cal; attitude check
Warmed up the Dynon for 30 minutes and executed the "zero pressure IAS/AOA calibration" i.a.w. Dynon manual. Static, pitot, and aoa ports were covered with microfiber cloths Iimages 1 and 2) and hangar doors were shut to eliminate air currents.
Put the mains on 3/4" plywood spacers and adjusted nose and right main air pressure to level pitch and roll (measured with digital level on the canopy slider rails and cross-beam behind the seats. With me in the cockpit sitting on the middle of the cross beam, the slip-skid ball is perfectly centered. Attitude indicator is at 0 degrees roll, but shows half a needle positive pitch.
When I was not in the cockpit or on crouched on the wing (which put the ball off-center, naturally) the AI indicated 0 degrees pitch. Couldn't get a good pic without leaning on the airframe. Tried different pitch attitide offsets and found that the default 0.0 degree offset was best. Looks like the platform I made for the ADAHRS units is in damn fine alignment,
With tire pressures at 40 psi for all three wheels, the ball is tangent with the left line. Pitch is about positive (about 1 degree) but roll is still zero on the AI.