In the Twilight Town Tram Common, before returning to the World Map, check the "Now Showing" bulletin board across from the Moogle Shop. There will be two posters on the board, Mickey, The Mail Pilot is the poster on the left.
"Collect the letters that fall out of Mickey's plane!"
Press to pick up the letters.
When it rains, the wind will cause you to lose altitude, so watch out for those birds and mountains!
Mickey, The Mail Pilot is based on Walt Disney’s 1933 animated short "The Mail Pilot".