Backronym needed.

Way back when I was first sketching out the nuts and bolts of the universe for Void Dogs... which was a while back before I started writing it... I came up with the idea of the ship's FLAG, which is basically a navigation and identification beacon that ships have that lets other ships know they're in the area, what kind of vessel they are, their registration, who they're affiliated with, etc. Back when I came up with it, FLAG stood for something. I can't for the life of me remember what it is. I remembered KEG, Kinetic Energy Gun, and I remembered that UTAH is the United Terran Alliance of Homeworlds.

So what's FLAG?

I'm willing to take suggestions... in fact, I'll make it a contest. The first person to suggest the idea I end up using can have their name put on a ship in the next Void Dogs story arc. Said ship may or may not explode.

Note that any variation of "Federal" or "Federation" won't work for the first letter, as there is no large federation to speak of and the FLAG protocol is used across political boundaries.

This is fairly open-ended, time-wise... I can keep referring to the FLAGs as needed in the story, as the purpose of the acronym is that they don't have to say the whole thing every time.