The list is not that long.

If you go to fly some acro dual, you will almost certainly fly an American Champion Decathlon or one of its historical predecessors. The other more expensive options will likely be a 2 seat Pitts, or an Extra.

If you are thinking about ownership, the list gets longer. There are a bunch of Pitts biplanes out there, Extras, Lazers, and now One Designs. You might run across the certified Zlin 242, Experimental Exhibition Staudachers, Zlins, Yak's, Sukhoi's, some Bucher's. You might run across a few Clip wing cubs and T-carts. In the homebuilt world you might see some EAA Biplanes, Skybolts, and some RV's that owners do Sportsman level aerobatics in. Once you get past that group, the population thins out a lot. The antiques like Chipmunks and the older biplanes are becoming family heirlooms and are less and less likely to be flown to the edges of their performance envelope due to their age.

So the above is a long winded way of saying that the list is short enough for practical purposes that the best place to find the info is to look at the acro school list where the airplanes used by each school is listed. Some folks might object to their favorite casual looper being left out of a list, and then you get into the liability of endorsing some airplanes that are not strong enough to do all of the figures that IAC pushes us to learn.

Best of luck,

Wes
N78PS