Sorry, if I seemed rude, but you did get me to thinking. I called a friend that has been in the hobby for 30 + years and asked him. He stated by IMAA, any mono plane that did not have a couther part with an 80” wing span is considered ¼ scales. Biplanes with 60” span with no counter part are considered ¼ scales. I guess if there is no counter part that is the standard for size rating. I think the baby bi has a 50 something inch span and is considered a ¼ scale, but has a counter part. Thanks Mode One, I think we both learned something. Again did not mean to be rude. It was late when I posted my stupid reply.

Freebird