Insurgency: Sandstorm

Hardest achievement in game. I personally did this in pvp frontlines with an RPG. I tried for a couple hours in the coop modes looking for drones and helicopters although I kept getting my kills taken. Others have recommended using the panzerfaust. Keep in mind when you do hit the helicopter, as it’s going down keep shooting it because all it takes is one of your teammates to shoot it and they will be granted the achievement. Best of luck

Edit: Unlocked this today after shooting down my third helicopter and stayed alive until it crashed, upon which the achievement immediately popped. I will attach the video when I get a chance to provide a visual aid. Just to add to information below, definitely use the Panzerfaust rather than the RPG-7 when going for this - you only get one round rather than two, but the rocket's velocity on the Panzerfaust makes it infinitely easier to account for the helicopter's movement. Also re-posting up here that it is imperative you do not die until it actually crashes as, unless fixed in the recent patch, you do not unlock it if it crashed while you are dead.

Clip of me shooting it down with the RPG-7. As you can see the crash kills me so the achievement did not pop.


Clip of me shooting it down with the Panzerfaust 3. The achievement popped right as you hear the audible crash of the Black Hawk. Bonus 'Blyat!' included.


Original:

So I've seen several sources (rather ambiguously) state this is best to do in Outpost PvE mode but at time of writing I have spent easily 10+ hours playing Outpost and have never seen an AI fire support used. I've also searched extensively on Reddit, Steam etc. and have found no guidance as to what wave, map, or any other specifics that would assist other than 'play outpost'. I'm not saying it's not doable in Outpost, but in my experience, it's certainly not 'easier'.

With this in mind I have had far more opportunity at least to attain this achievement in PvP as fire support is used by players (at least in a fair amount of games).

If you are playing as Insurgents, I would suggest using the demolitionist class as much as possible to shoot down enemy air assets when called in. This is easier said than done however as the choppers normally stay quite far away, will actively dodge rockets, and will kill you very quickly. I have also heard engaging with the anti-materiel rifle or MG3 while aiming at rotor blades works, but can't say I've had much success. You will also have many games where the team doesn't bother using Fire Support (usually with the result being an easy win for you but no attempt at this godforsaken achievement).

As Security, I would recommend playing Gunner with the FN Minimi. The Suicide and Bomber drones (apparently) have lower health and the 200 round belt and ROF of the Minimi should be more than capable of taking these down. 'Should' being the operative word as these call ins are unfortunately seldom used in comparison to others.

Note I have in fact 'earned' this achievement twice (one shooting down an AH-64 - I have a recording of this, and once on a UH-60). Here's the key bit though, I can tell you from my experience and at least one other similar account on another site - if you die before the air vehicle crashes, you will not get the achievement. As such, be advised, the description of the achievement should actually be 'Destroy an enemy air support vehicle (and don't die before it crashes)'. In a game where a single bullet will normally kill you. Yeah, great.