Ideally, IMAC judges would judge any plane for performing a manuever, according to rule book standards.

Real world, pattern planes in IMAC are automatically downgraded for not being "in the mold" and smaller planes are downgraded for simply not being bigger, and faster planes are downgraded for going too fast.

Before someone blasts me, I have seen this, have been told this, and simply happens. However, most is not an intentional thing, but more subconscious. We are human after all.

Last year, a nice guy in Basic flew a cub. I would fly anything in Basic, and if you wish to be a little different, research the list of planes that have competed in aerobatics. There are a large number, and some a fairly unique.

Ed