On the left is the early Blue Angel tail assembly and on the right the late. The early Blue Angel uses slabs of balsa for a vertical stab and uses only small blocks of balsa beside the stab base to fair into the fuselage. This makes more of abrupt change between the fuselage and the stab compared the late that uses a large hollow balsa block that makes a smooth molded like transition from the fuselage to the hollow built-up stab base. The built-up vertical stab on the late is much thicker. From the top view the early fuselage sides flow directly into the leading edge of the rudder making the fuselage narrow. On the late the fuselage is wider than the front of the rudder by about 1/8” on both sides. So the back of the fuselage is a least ¼" wider. The base of the early vertical stab is about 3/8" and the base of the late is about 1”. The rudder on the early is taller and the stab cap shorter. The lower part of the fuselage on the very back is not a carved block like the late.

The drawing error on the late plans where they have the rudder pushrod connected to the rudder in the wrong place causing interference with the elevator is not present on the early plan.