My record is 54 minutes 13 seconds.
The best way to fly it is to use these easy steps I made for you guys.
Its really not that hard.
1] Get in the Dodo at Shoreside Vale.
2] Go to the end of the Airstrip by the ocean in the back. (Not the end as in the end of the actual flying area)
3] Begin to fly.
4] hold the analog stick all the way forward.
5] When you see sparks under the plane, let go of the analog stick.
6] Then, slowly
get yourself parallel to the ground. (not pointing towards the ground, or up towards the sky)
7] If you want to turn, just barely TAP the stick left or right slowly, thus allowing you to turn easily not causing you to spin out, which is bad.
8] The only bad thing about the Dodo is that when you take off and get yourself straight, as soon as you are parallel to the ground at the level, you really cannot increase your altitude, its very difficult, every time I've tried, I stalled.
Hope that helps.