Here is the full list of all 19 SKYCAT achievements.
Welcome to SKYCAT!
Arcade mode clear!
Misson NOVICE complete!
Mission EASY complete!
Mission NORMAL complete!
Mission HARD complete!
Mission EXPART complete!
Cat complete!
Plane complete!
Shot complete!
Accessory complete!
UUDDLRLRBA!
New Friend 1!
New Friend 2!
New Friend 3!
New Friend 4!
New Friend 5!
New Friend 6!
New Friend 7!