I can do this 100% of the time now. Super easy (if you are half decent in this game).
There are only 9 waves on the first survival map (called survival)
Here are the units you need.
1) patcher (repairs your units)
2) t99 turret (kills tanks)
3) lunchbox (gives your base shields)
4) optional: warthog airmech (sit on top of your base for unlimited flight power, hold RT and fire at incoming enemies, you will never run out of bullets this way)
On the first wave, try to build soldiers and capture as many bases as you can for max money. DO NOT KILL incoming guys yet, the longer they survive, the longer you'll have to prepare your defenses. Once all the outlying bases are captured, build t99 turrets NONSTOP FOR THE REST OF THE GAME (spam Y button).
If you've done everything right, your base should have a little scratch from wave 1 when we ignored the incoming hostiles. After wave 2 you shouldn't be taking damage for the rest of the match.
You can also pop
The Miser achievement in AirMech Arena (Xbox 360) worth 36 pointsReach Level 10 in game with any AirMech, and win without spending any Ability points.
easily once you got this survival strat nailed down.
The first wave will come from the north, place your turrets there, near your base, just before the bridge. DO NOT PLACE YOUR TURRETS ON THE BRIDGE, PUT THEM CLOSER TO YOUR BASE
For the first 6 waves, the baddies will only attack you via the bridges. They do not have any air units so do not bother with air defenses.
2nd wave attacks from the NE, place your new turrets there
you can start placing lunchboxes (provides shielding for your base) around this time, they must go into your base sockets.
3rd wave attacks from the SW, place your turrets there
Around this time, your base should be very well defended, maybe 2-3 turrets per chokepoint at least. Now start building patchers to automatically repair your units. At first, 1 patcher per chokepoint is good enough, later on, you'll want patchers overlapping each other so they repair other patchers.
around wave 5 or 6, they will come from the SE, place your turrets there. Up until this point, all the baddies only attack from the bridges.
around wave 7 or 8, they will send infantry that will lightly damage your outer bases (you can ignore them though), and will attack you by going up the ramp to your base (now they do not attack exclusively via the bridges).
Wave 9 is the last wave, you should have max turrets (129 slots available) around this time. If you spam Y really fast you can over-build turrets (135 slots used out of 129). About half way thru the battle, you'll lose all your outerbases, DON'T WORRY ABOUT THEM. Just attack those big ass tanks lobbying bombs at your base with your airmech. With this many t99 turrets you should easily end the battle.