RE: Sturdy Birdy II
If the Sturdy Birdy Had been a good trainer it would still be around. Bottom line the airplane was flyable but truly awful as a trainer, in addition the concept of an Indestructable trainer was also a horrible concept and a lie. It was certainly not indestructable.
I have flown both variations (with and without ailerons) in the past neither was much good as a trainer.
In addition be very careful when helping your friend These wonderful 'finds' in almost every case end up costing the fellows far more money than needed and make sure that the radio system is actually still legal and not old wide band land fill. Remember at the very least the RC systems batterys will need replacement both tx and Rx.
John