when I first got my NEXTAR I definatly had to file the holes in the landing gear to get them to snap in . also with the flaps installed you need a bit of down elevator trim to get level flight when you remove them you/your instructor should re-trim for level flight and like the rest have said check all bolts after several flights my head bolts were loose the ones on top of the motor just a bit but they needed snugging up a bit also the antenna wire needed to be routed out of the fuselge to get it to pass a proper radio check your instructor will go over that for you . other than that this is a great first plane a real floater easy to fly and land it helped me on my way for sure