Operation "Stormy Petrel"

Kuznetsov has tasked you to find and mark 23 crashed helicopters located at Radar, Central Pripyat, CNPP-1, CNPP-2, Jupiter, and Zaton respectively.
==Walkthrough==
Find all crashed helicopters on these locations; they are out of level boundaries sometimes. On each helicopter, you'll find a spot to install a GPS Beacon; it's near the main rotor axle. Interact with it to install the beacon. You'll have to buy the beacons on your own.
All 23 helicopter locations are shown on the video below.
==Notes==
* You must forget about Stormy Petrel
==Bugs==