It's going to be a nightmare to clean up the polluted data in the aicraft table :(
You must be able to come up with an SQL query that can tell the difference between numbers and letters - is there an ascii type filter?
Do that a couple of times, export, import etc - piece of cake :-0
Except for the companies that start with numbers, and the serial numbers that start with letters - agghhhhhhh..........
Maybe I'll just leave it as it is!