the author of this app says:
In many cases, the ability to find airline names and codes or airport city names and codes is critical. This tool provides such information by searching a partial input of letters.
If you're a frequent flyer, there are times when you need to know the two-letter code for a particular airline to get necessary information. For instance, this information is necessary when you use your wireless Web mobile phone to check on a flight time. You might also be on the internet trying to make flight reservations and find that you're in need of the three digit airport code for departure or destination reservations.