As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING PREFLIGHT THE PILOTS ALTIMETER WAS FLAGGED. THE ADC WAS FOUND TO BE DEFECTIVE AND REPLACED. THE SYSTEM WAS TESTED AND INSPECTED AND FOUND TO COMPLY WITH FAR 91 AND TO REMAIN RVSM COMPLAINT. THERE HAS BEEN ONE PRIOR FAILURE REPORTED ON THIS SYSTEM REPORTED ON 11-11-2005. (K)