ORIGINAL: vbortone
The 5 Kg rule is probably the most universal FAI rule (could be considered a limit to define RC model airplane for international competition ). There is only one exception for scale planes that allow a little more for obvious reasons. Looks like is going to be very difficult to increase this limit in FAI. We already did in AMA so I don't see what is the problem for the AMA Master class.
Here's some of the problems in Masters Class.
1. Pilot X wins the 2012 Nationals in Advanced with a 5,100 gr plane. Next year he is required to or wants to move to Masters Class. It's going to cost him $$$$ to fix his weight problem. For what benefit?
2. Pilot X shows up at a contest with 5.100 gr. plane and he's the only pilot entered in Advanced. Rather than fly by himself, he decides to compete in Masters. OOOOPS! Not legal!
3. Pilot X with a 5,100 gr. plane wants to give Masters a try at a local contest to see if he's ready to move up. OOOOPS! Not legal!
4. Masters pilot Y mid airs at a contest. Want's to fly his buddy Pilot X plane the rest of the contest which he has flown in practice and is familier with. OOOOPS! Not legal!
Lots of bad unintended consequences to the rule change for the lower classes perhaps? I think it was a bad change. All AMA classes should fly by the same rules IMO