i found a little trick on this level. you fly behind the aigaion (the biggest plane) as soon as you can and take out its 6 flak AA on the back. now head to the inside of it, near the middle, and slow down as much as you can without stalling. then when the strigon team take off one by one, you can fire your gun at them, but you cant kill them....they will however be severely weakened so they're a lot easier to take out when you order your allies to attack them. you should look at the walkthroughs on here for more help on that level.