Have not flown mine yet. I still have the upthrust still in it. I wonder if Bob's does not have this upthrust problem due to him using a heavier power system by using the 20 cc gas which I believe would make the plane utilize the upthrust. Have you done the knife edge test that BJ mentions in the setup? If so I would also like to know what batteries your using and what is the overall ready to fly weight if available. Thanks in advance.
Terry