Call of Duty: Modern Warfare 2/Suspension

Walkthrough
You start at the beginning of the bridge, where there will be a lot of guns. Choose any gun you're comfortable with, but you should also replace your handgun with an RPG or a Thumper, because you'll come across a gunning helicopter pretty soon. A Thumper wouldn't be so useful against a helicopter, but it would be very useful to blast any enemies hiding behind cars. After shooting the vehicle, it will explode, hence your annoying enemy goes flying.

After you've taken your time with choosing a gun, take cover behind a car and shoot the bulk of your enemies when they're dropping in via grappling rope. It's impossible to get all of them as they're coming down, so for the next part, just shoot and take cover. Also remember to be careful when hiding behind cars. If your enemies shoot your shield to much, it will explode. It's a pretty dangerous position to be in, so try to get behind a car that already exploded. It won't be the best shield, but it's not as dangerous as staying behind a burning car.

After you've pushed through most enemy forces, even more will drop in. Go through the same pattern until you reach the huge truck. Make sure there are no enemies behind you. If there are, you'll regret it afterward. After making sure all of your enemies are dead, go past the truck to experience the bridge tilting a little. It's impossible to run while the bridge is tilting, so just walk through the whole progress calmly until it stops. After this, keep running and you'll reach a place where the bridge is unnaturally tilting upwards. Jump up this part to see a helicopter and many more enemies. This is where it gets a little tougher.

You'll have to stay out of sight of your enemies while shooting down the helicopter with an RPG. This will take quite a few shots, and it's normal to run out of ammo for your RPG. This shouldn't be a problem, as there are more RPGs a little ahead of you. Keep blasting the helicopter. It'll take about five shots to go down. When it starts spiraling out of control, start to focus on the people on the bridge. Slowly push past the people with your gun of choice, as it would be devastating to die at this point.

When you see the green smoke, you're close to the finish. Either keep shooting or make a run for the finish.