Level eleven of the Axis campaign in iBomber Defense takes place in Western Europe, facing off against three main incoming paths of ground units for 45 waves. Units coming from the red path can actually take one of 3 sub-paths upon reaching the split as depicted to the right before merging again just before the base. Aircraft will arrive to join the fray at the beginning of wave 24.
Turret placement will at first focus on filling up the spaces that exist in the middle of the circle made by the splitting and subsequent merging of the red path, along with the subsequent joining of the orange and yellow. From there it will be spread out to occupy the 3 plataues to the west once this first portion is established sufficiently.
Your initial placements should focus on getting 6 fully upgraded Machine Guns up and running in positions where they can best cover the multiple incoming paths. Once those are down, place an Inferno turret next to where the yellow and red paths are merged and the orange and red paths, preferably on the inner edge of these roads so they can stop the red path traveling through the middle. Finally , you should be able to save up for a single X-Weapon with the numerous weak units that come during these waves, placing it in a position where its power is boosted by your’re already built turrets.
From waves 15 through 25, your focus should be on getting a second X-Weapon, then upgrading both to level 2 while upgrading the Inferno turrets. Placing a couple Cannons is good measure during this time in positions where they can boost the X-Weapons. Finally, make sure you have your Anti-Air up by wave 24, a good position for this being the southern hill.
Proceeding onward to wave 35, work on upgrading your X-Weapons to their final levels to start causing the really big AOE splash damage that turns the tide in the Axis missions. Once they are built up with upgrades and turrets to boost, preferably Cannons, start working on a new X-Weapon. As you can see in the pictures to the right, four fully upgraded Cannons are possible by wave 35 with work beginning on the fifth. Feel free to start selling some of your Machine Guns for placing more valuable weaponry.
You can continue this strategy along towards the final waves, eventually building up X-Weapon bases on all 3 hills. The western hill is an appropriate spot for a 3rd and final AA turret for good measure.