Online quest Hellbound without Alert status impossible.

[Atréju]

The helicopter is scripted and not dismissable. The challenge is impossible. Pls remove that Mission

[shoopy]

It's not impossible. It's not even hard.

https://steamcommunity.com/sharedfiles/filedetails/?id=3007660483
https://steamcommunity.com/sharedfiles/filedetails/?id=3007660600

The mission is quite easy except for Sahelanthropus being annoying, but he doesn't affect anything.

[Atréju]

Why do you bother answering and even attaching screens if you don't explain how to do it?

[shoopy]

Originally posted by Atréju:

Why do you bother answering and even attaching screens if you don't explain how to do it?

Because you beat it the same way you beat any other mission. The helicopter doesn't affect anything, you simply don't get spotted. There is no special way to do it.

[shoopy]

Here's a guide. I didn't even do it this way, so you don't actually have to follow it to be successful.
https://www.youtube.com/watch?v=7lqoy-zShyc

I think the only important detail is to carry Huey and not take the walker.

[!RJ_Truth]

Originally posted by Atréju:

Why do you bother answering and even attaching screens if you don't explain how to do it?

Do better. Don't be a D**k

[shoopy]

Redid this to get the S rank also.
A couple tips I have:
Bring D-Horse
Exit the power plant on the left side and go along the top of the pipe.
Ride D-Horse to the base and use his stealth mode to help you sneak in. This takes you to the west side which is easier and closer to Huey.
Carry Huey out without the walker. You can use him as a throwing weapon to run up on guys shooting at the chopper, they won't notice you and you can throw Huey at them to knock them out.
Run right between Sahelanthropus legs then move the chopper landing zone to the next further one, get on D-Horse with Huey and ride there. You should be able to lose Sahelanthropus on the way so you can just get on the chopper and leave.

[Tyrant (My Vision is Augmented)]

Was confused by this post, so I just replayed the mission and got an easy S rank and no detection/ alert status/ kills (and also extracted every enemy in the level just to walk around it a bit and explore). I left the helicopter intact and it never noticed me.

The above post from Shoopy is solid and will let you avoid the most frustrating part of the mission (Sahalanthropus), but I took a different approach.

Non-lethal handgun, non-lethal sniper, and a supressed AR, with a sneaking suit and D-Dog. Make sure your combat deployments have eliminated helmets and body armor (shields are nice to be rid of also), and start the mission at 1800 hours. Bring a resupply flair, especially if you want to extract a lot of dudes.

From here, DD will basically give you wall hacks and you can easily eliminate every outpost you come across. You can skip through the power plant at the beginning of the mission with only one or two KOs, and just be patient and move when the helo is further from you. It will land on the roof for a bit - just wait for it to fly off while sticking close to the large building (left side as you enter).

Eventually, arriving at the final base, my recommendation is eliminate everyone- or close to it. Eventually the helo will fly off, and you will be able to quietly snipe everyone from a distance in the dark. This makes walking out with Emmerich a simple task. Even if it takes until sunrise, a new guard shift will not repopulate the base (I waited around to check).

In short - this mission isn't any more difficult than most of the standard infiltration/ extraction story missions in the game. It's arguably easier than most, as there are no Skulls, very little close-quarters/ interior spaces, and no real vehicles/ armor to be concerned about. Every problem in this level can be solved with D-Dog and a tranq sniper rifle - putting it in the "easy" category from my perspective. If the helicopter is giving you trouble, just be more patient - it makes wide circles - so plan your movements (and eliminate guards from a distance).