This is fairly easy.

1. Fly around Snowstone until you unlock "Ice Base Assault" as a location. Change your location in game to "Ice Base Assault" and exit flight mode.

2. Make or edit a medium-sized aircraft (preferably one with jet propulsion) and line the front of its primary wings with wing guns.

3. When you start back in simulator mode you should be flying straight at the Ice Base. Simply hold down the trigger to prevent missiles from hitting you head on. At the last moment you may see a hole just above the AA defense system...that is the runway connecting to the secret ice base in SnowStone.

4. Once inside (or if your cockpit happens to land inside after being shot out of the sky and crashes inside) just use "Restart Here" and save the location.

5. Re-select that location and exit out and load the Little Bugger and start simulation mode again, and you should be inside the base where you saved and selected said location.

6. Position the Little Bugger to where you want to take off from, then delete the ice base location you saved previously and save the new one with the same name you used before.

When you take off from the runway inside the Ice Base, the AA Defense system will not bother you. while flying in Snowstone.