Hey Jet,

Not sure if you found a solution but I came across this Honeywell FMS news letter: http://www.honeywellaes.com/servlet/...7B36EMNJ4N0FXS

In the question and answer area at the end there was this question and answer:

Question 14: What will cause the system to drop from FULL PERF mode to CURRENT SPD/FF mode and
display the message FULL PERF UNAVAIL?

Answer 14: This is generally caused by a corrupted aircraft data base. This problem can be resolved by either
reloading a previously saved customized version of the aircraft data base or reloading the basic
aircraft data base file for that aircraft type contained on navigation data base disk 5.

Hope this helps,

Kevin