Can the microEFIS be used as the only attitude gyro?
In certified aircraft, the microEFIS is used as a backup to the primary attitude gyro/vacuum system. In experimental aircraft that are used for IFR flight, again the microEFIS is a backup system. In experimental aircraft that are VFR only (no installed gyros), the microEFIS may be used as an emergency gyro should the aircraft encounter unexpected IFR conditions.