Gemini Pro Long Range Test Flight (Vibration issue fixed-Mostly)

Another flight to check performance of the Gemini Pro test airframe.
The previous vibration issues have been solved, (mostly).
the issues were:
Dynamic balance needed on the props, instead of just blade weight equalization (this was a larger issue that it should have been just due to getting one prop that was out of balance from the factory).
Harmonic between the motors and the nacelles, (elascitity), solved by adding doublers on the inside of the nacelles.
The origin of the vibration seems to be due to inevitable P factor loading, at some RPM's and angles of attack, playing into the flexible nature of the nacelles prior to adding the doublers.
believe it or not, everything flexes, even if it is made of solid steel, or carbon fiber.
The only remaining vibration seems to be due to the props causing a section of turbulent air when windmilling (in this case the blades are cupped the opposite way as to normal, causing blade turbulence) and this is blanketing the section of the wing behind the prop, and causing a slight turbulence.
this seems inevitable in a twin tractor configuration. It could be solved by performing powered descents, where the prop RPM is increased to correct the flow of air over the blades, or by braking the motors using ESC programing.
We hope that this is a good demonstration of some of the capabilities of the aircraft, and is educational regarding airframe elasticity, prop balance, and factors of vibration in twins using 2 bladed props. This is part of the reason why freestyle and racing quadcopters use 3 bladed props. We used a Dubro prop balancer with very good results. They are very accurate and actually better than the magnetic type.