Avid tail differences

[Benbell4140 0]

I'm looking at buying a an avid mk4, can you tell me wich tail came out first? One that I'm looking at has the rounded rudder. Then I see some others have a more square shaped rudder. Wich is newer? What years did they change this and why? Is there an advantage to one compared to the other besides looks?

Thanks

[Trackwelder 12]

The tail is only one of the differences between the markIV and the A B and C models, and the easiest to change if someone wanted to fake a Mark IV. The first thing I would look at would be the spar carry through tubes should be 1 and 1/4 inch and the ends will be welded closed. the size of the fuselage wdth is also different.

[C5Engineer 1170]

The round table was the later of the two. It has slightly more area than the square one and was supposed to help with rudder authority during slow speed operation.