I was flying around kyrat so I decided to go through the mountains
to the fortresses not yet conquered using the buzzer.
But every time I try to do that, he whistles and starts to fall. Why does it happen? Is this why I have not yet unlocked the map part or another reason?
Here is an image of the buzzer in case someone doesn't know what is it by the name.
Best Answer
From what I remember when I played this game, the Buzzer has a maximum altitude that it can reach. Once it surpasses this altitude, it will set off an alarm to warn the player that it is about to stall out. If it stalls, it will begin to fall to the ground.
From the Wiki page:
Based off your question, it seems you are flying too high with this vehicle in the mountain area.