Yes it is 1/2A size, I flew Antone Kephart's model on Saturday. His is powered by a Tee Dee .049. Dang, that is one fun airplane to fly. I'll get a new one on the building board soon.
My original model had a variety of engines over its lifetime, the one in the photo is a PAW .049 Diesel.
Just a word to the wise, if you plan to fly 1cc at the Mackey Open meet, be prepared to do over 500 points if you want to win. Antone and Stan are brutal! (They cheat, they practice!)