As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RTB DUE TO CAPTAINS VSI BLANKING. SWAPPING C/O FOLLOWING DELTA MCC REQUEST. VSI FOUND FAULTY - PROBABLY STORE FAIL. PROPER CONFIGURATION RESET CAPTAIN VSI REPLACED IAW AMM 34-22-06-004-001. CHECK C/O THROUGHOUT 2 HOURS. NO FAULT FOUND. ETOPS CATEGORY 'E': PROBLEMS WITH SYS CRITICAL TO ETOPS.