WATCH_DOGS

Here what I did to get these achievements Scanproof and Free radical, and I only compete the first mission so I don't have comms jams mentioned in the other guide(s).

I took a type of speed boat and went up and down the big waterway between the loop and Brandon docks near the large shipping ship (easy to see on the world map) shooting people till I got to level 5.( if you trigger it early or it becomes a chase just drive out to open water to stay ahead of the helicopter, it will end soon.) when the scan starts drive out to open water were you can easily avoid the scan, They will still appear out there so don't stop moving. After about 1-2 min it'll stop and achievement will pop.

This is a helpful option for those who might be bad at driving cars as I am.

Before you start you want to have the max amount of comms jams possible. For me it was five but I'm not sure if skill sets increase that cap. You can craft them yourself if you have the skill or buy pre-made comm jams from Tobias if you have reached that point in the story.

For this your CTos level needs to be at 5. It works like a wanted level, but sticks around after you lose the cops and slowly drops so if you pick up the cops again you start at that level instead of starting at level 1. The fastest way to get it to level 5 is to kill police officers but killing civilians also works and is much easier.

Kill as many civilians as you can and watch the bar build in the bottom right corner. As soon as you see a red triangle in the corner that means someone is calling in the police, Kill them quickly and then get back to killing civilians until the white bar at the bottom is completely full.

Then get to a fast car, something with speed but that you are comfortable making sharp turns in. And let them call in the cops. You'll see a yellow circle on the map, stay out of it. If you're in it too long you will be detected. These yellow circles will pop in and out on the map and some move about. Try your best to dodge them.

If you get trapped in by or your detection bar nearly reaches 100% them trigger a comms jam and try to get clear, it should buy you enough time to get free. On my attempt at this I used 3 comms jams and I was being quite liberal with them. After some time, (I'm unsure how long, there doesn't appear to be any indication how long of the the scan is left) the police will break of the scan and you'll be home free.

** Huge thanks to MAKA91 for the video guide below for this method**

SUPER EASY SOLUTION ... Go to the docks and find a fast boat. Start shooting civilians until you get a 4+ scan level then escape the area. Return after your escape and you should still be at a scan level of 4 or more. Depart the boat at a dock and start shooting again - will only take a few seconds to get to scan level 5 and you should at 5 prior to anyone calling the cops. Back in the boat and head for open water and you can outrun the scans or block them ... your choice. Really, really easy.

Use the Papavero Stealth Edition which can be unlocked as a Uplay reward. You need 40 uplay points to unlock this.
The stealth edition isn't only looks it actually adds a stealthcomponent which makes it easier to escape the scan. When I used it I did not even need to use any comm jams.

The easiest way I found to do this is to get 5 jammers, go on a bridge, and start shooting people in their cars on one side of the highway. the npcs have to get out of their car to call the cops, so this makes it easy to get a five "star" wanted level. once you get that let some one make a call then jump to the other side of the bridge, get a car, and drive away using the jammers as soon as the scan turns green.

This guide contains some spoilers - please be aware.

I unlocked this without damaging my reputation much (I stayed at vigilante level) in act 4 mission 2 - in plain sight. Unfortunately this method is time sensitive as you cannot replay missions, but if you want a consistent way of getting 5 star scan without the scan starting early and you want to protect your reputation then this is a great way to unlock this achievement.

Before the mission starts, you want to max out all of your jamcoms and have as many system (one time hack) keys and electronic parts as you possibly can - the profiler optimization skill will really help with this as if you are low on system keys, a blue box will appear around people with valuable items to hack and system keys become more common. I have been able to get up to 8 system keys maximum but for this mission i had 5.

When the mission starts, you will already have level 4 police on standby. Find a fast car, secure it and kill a couple of civilians. This will get you to level 5. I then allowed someone to call the police - this next part might be easier if you kill anyone calling the police so that you buy more time before the scan starts.

Chase down and take down the van, using jamcoms to keep the scan level low (craft more jamcoms when you feel you have a spare second to do so) - the best way to do this is to follow it closely until you get the option to 'neutralize'. I did this at traffic lights. Run over the target and immediately load the map. Put a way point to Brandon Docks and make sure it's a relatively clear path - the more straight, the better. It is definitely preferable if you are also facing the same direction as the path you will need to follow.

Follow the path using jamcoms where necessary and eventually you will escape! Achievement unlocked and mission complete.

If you fail at any point, ie. You run out of jamcoms, truck taking too long to take down, you crash heavily or get caught by the police, restart and this will take you back to the beginning of the mission.

You will also unlock free radical and make progress toeards white rabbit object whilst following this.

Video of me earning this achievement below. Good luck!