It took over three years to build my DR-107 One Design, and it received an airworthiness certificate on March 30, 2016. I now have completed Phase 1 testing and I'm extremely happy with the performance of the airplane. I made every effort to build it as light as possible, and achieved an empty weight of 870 pounds, which is very light for a DR-107. It is an incredible aerobatic performer and works well as a fun sport plane too. I used the Polyfiber products to paint and cover the aircraft. It has a Superior IO-320 equipped with inverted fuel and oil. I installed a Catto prop made for the airplane, and it works great.
I wanted to build a DR-107 during my long military career, so when I retired, I did. I can say it is certainly worth the time, money and effort. I've had numerous experimental aircraft, but none that is as much pure fun to fly as the DR-107. Many thanks go to Dan Rihn, the designer, who was always available for guidance and support, and the many builders and owners of DR-107s that were of invaluable assistance.