How about just writing lat/long instead? No confusion on whether it's an IATA or ICAO code, no problem if a field has neither. Oh, and use the phonetic alphabet, in morse, to write your name. Hexadecimal to write down your passport number. And time in seconds since epoch - which in this context is the first flight at Kitty Hawk.
No wonder nobody ever shows up to check your form.
(Allright, it's Christmas eve and I've had a drink or two.)