Play Conquest on any End Game map. Now, your first objective will be to capture the flag with the gunship symbol next to it (usually C) or make sure that your team has it. When you have that flag, you will have to wait for the C-130 gunship to spawn (or respawn) and then you will have the ability to choose "Dropship IFV", which will then drop you from the ship while inside the IFV. Now, when you land, you'll need to get at least 1 kill using the IFV. It is recommended that you aim for enemies that are on foot. Watch out for enemy tanks, helicopters, mines and rockets as the IFV is not very strong.
Once you get a kill an enemy, the achievement will unlock.