Killzone 3 Walkthrough - Icy Incursion: Part 2
8Full Walkthrough: http://www.gamefront.com/killzone-3-walkthrough/
Take cover or at least stay down on the right side and fight off the few Helghast who are down here on the rig deck. Once you've killed the guys on the lower two levels, climb up and head for the stairs on the left. You'll see a trooper waiting for you — you can blow him up by hitting the barrel there, which destroys the stairs. Fly over them to get to the top.
The area below the AA gun is crawling with Helghast, so find cover and keep moving. The cool thing about the jetpack is that you have a lot of tactical options about where you want to stand when you fight — a good spot is actually across from the AA gun on the other side, one level up.
Whatever you choose to do, your strategy is just to keep from getting pinned down or blown up, and clear the guys from beneath the AA gun. Your jetpack's SMG fires a ton of rounds and rarely overheats, so it's handy for dumping a ton of ammo into enemies. Its not too accurate, though, so you might want to switch to your assault rifle when at range.
Plant a demo charge beneath the gun when you're finished killing everything. After the cutscene, jump off the edge of the rig and fly down to the ice berg. Travel across the bergs until you hit a big ice flow just short of the next oil rig.
You'll have to clear this position of a lot of enemies — about three riflemen at first, then a few jetpackers, then some other Helghast deployed from a drop ship. The jetpack SMG should serve you really well here. Clear them out, then hit the objective button to highlight the big blue fuel pipe you have to shoot on the rig.
Full Walkthrough: http://www.gamefront.com/killzone-3-walkthrough/