My project was an RV3b started January 12th, 2002 and my first flight was September 23rd, 2012.
It would have gone much quicker but I did not have much money so I built it as I could afford it. I don't even have an aircraft engine because of the cost but that part perhaps added at least one year or more to the build time because of all the custom parts I had to make or have someone else make. I even made my own motor mount. I decided that I wanted fuel injection so I had to learn how that works. Programable injection controllers are expensive but I found a fuel injection kit that you put together yourself called Megasquirt II that cost only 250 dollars. It was winter time anyway and I did not want to go out in the cold garage, "I live in Minnesota" and work so I bought the injection kit and read all the directions and soldered each part to the circuit board. Then I had to learn how to program the thing. Then I decided I wanted to turbo charge my engine, oh boy more learning... After much reading I purchased a used turbo on e-bay and then purchased new parts to re-build it.
I had to purchase a 3 blade adjustable propeller to I could load the engine at any RPM so I could program the injection computer. After much testing and many ideas that did not work which can seem quite daunting and depressing at times. I remember times that I would go to bed at night so frustrated because I did not have the foggiest idea on how to make a part so I turned to God and prayed before I fell asleep. In the morning when I woke I knew how to make the part, this happened several times so for those that do not believe in God it may take even longer to build their plane, or it may never get done.
I am still working out issues after each flight. Sometimes I spend several days working on things after just a one hour flight. But most of my issues have to do with the experimental engine setup. I have a Corvair engine with a CJ5 Jeep starter wound backwards, a Harley Davidson starter ring gear mounted just over the harmonic balancer, a Ford throttle body, a Ford Thurnderbird Garet T3 turbocharger, Megasquirt II injection computer, Ford Mustang injectors, copper water pipe "homemade fuel rail", and many other custom parts all which must be tested. The DAR inspector sure liked looking at it. Then gave me a stern warning not to fly over any people, houses, etc... except for take off or landing.
It has been alot of fun and learning to build the RV3b aircraft. I would not advise most people to build an aircraft because of the time it takes to build and the patience that is needed. It took me just over 3000 hours to get to the first flight and since then about another 100 working out issues.
One of the reasons I wanted to complete it is to lead my children by example on how to complete a project.