Isn't a prominent theory is that it's meant to be "Sky Carry" but it got a little mangled in the translation?
I think it's a Japanese grammar thing? The katakana for "kya" in "carry" becomes "gya" with the addition of the dakuten ("), probably due to the sounds its following? (It has been many years since I actually studied Japanese)
Machine Robo has the Jet Garry and Machine Robo Rescue had Siren Garry, which are both essentially carriers for smaller figures, so it has to be a grammatical quirk because it follows another word. I think, if "carry" was the lead word, it would use "kya" without the dakuten. I think.