My 2 cents
If you follow the PAP instructions, you can make the plane fly 'straight'. Actually, I think it needs to slightly turn left if by yourself. Then with 2 people, it flies straignt or to the right slightly. That is how I ended up with mine. If you set it up for yourself only, when 2 people, it will not be the same. I'd suggest following the PAP instructions - THEY WORK !
John Bender