To increase your altitude BEFORE you've taken off, press Y then F4. When you want to stop going up, press Y again. Anytime during the game press "y". You will stop and so will everything. On the top it will say "slew" Then press either F2 to go forward or back and F1 to stop. Or press F4 to go up or downand F3 to stop. Also when you are in "slew" mode you can the can go forward, back, right left using the arrow keys on the keyboard or the joystick. When you are done press "y" again.
