As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SUREFLY SIM PRODUCED WHAT SOUNDED LIKE AND FELT LIKE DETONATION IN THE PHASE OF FLIGHT FROM CLIMB TO CRUISE WHEN PROP RPM WAS REDUCED. INFLIGHT TESTING SHOWED DRAMATIC TEMP DROP IN EGT IN CYLINDERS 3 AND 4 WHEN SUREFLY WAS SELECTED ONLY. SUREFLY SIM OPERATED NORMALLY DURING "MAG CHECKS" AND DURING HIGH POWER CLIMBS, BUT FAILED TO PERFORM PROPERLY WHEN TRANSITIONING TO CRUISE.