As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT RETURNED TO FRANKFORT DUE TO GPS NAVIGATIONAL ERROR. RESET GPS (ALL THREE UNITS) BY SWAPPING NAVIGATIONAL DATA, TO EXPIRED DATA BASE AND BACK TO ACTUAL NAVIGATIONAL DATA BASE. ALL FUNCTIONS BACK TO NORMAL. DATA BASE RELOADED. (M)