If you have ever been to an airshow, you know that performers have smoke canisters on their aircraft that make lines across the sky. I thought it would be really cool to have one of those in Blockland. Im guessing it would probably work like stratofortress's planes when they have White smoke from light damage, only the trail would be longer and stay around for a tad bit longer.
Some examples:
(Just look up Geico Skytypers, Sean Tucker, John Clatt, Blue Angels, Thunderbirds, or any other airshow performer).
Some of the ways this would be useful is for
A)Entertainment
B)Rps (If you wanted to)
C) To see someones maneuvers and learn from them
D) Formation flying, and to make adjustments and corrections
E) Just about anything else you can imagine!!
Note: This would be an ITEM, a "Click and spray" item