durabol
Well-Known Member
I want to build an amphibious airplane with a mid engine with a propeller on the tail. Due to the engine location and the propeller/gear reduction the plane is tail heavy and requires around 250lbs of counter weight in the nose for a 1000# gross airplane. I got the idea of a lifting tail in the book "Unconventional Aircraft" by Peter Bowers, which describes the Dornier 212 as a good example of a compromise and used a lifting tail for the same problem I ran into.
For the lifting tail I am planning on using 1/3 the area of the main wing which is about as large as practical as I don't have to remove the tail for trailoring. Although I will use a large tail, which should help stability, I think a lifting tail airplane tends to be less stable than a conventional tail, which is a concern. I am also concerned with the CG since the pilot sits on the main spar (to operate KR-2 like retractable gear) and the passenger compartment is in front in the nose of the airplane unlike a normal configuration where the pilots weight balances the engine and the passenger sits close to the CG. I was hoping I could balance CG with the lifting tail so I could have a wide CG range and wouldn't have to worry about weight and balance but perhaps this would cause too much trim drag or be unstable?
Brock
For the lifting tail I am planning on using 1/3 the area of the main wing which is about as large as practical as I don't have to remove the tail for trailoring. Although I will use a large tail, which should help stability, I think a lifting tail airplane tends to be less stable than a conventional tail, which is a concern. I am also concerned with the CG since the pilot sits on the main spar (to operate KR-2 like retractable gear) and the passenger compartment is in front in the nose of the airplane unlike a normal configuration where the pilots weight balances the engine and the passenger sits close to the CG. I was hoping I could balance CG with the lifting tail so I could have a wide CG range and wouldn't have to worry about weight and balance but perhaps this would cause too much trim drag or be unstable?
Brock
