Stalker: Call of Pripyat → Skat-2 and area maps
So, after searching the Skat-5, we're moving on to the second helicopter. We're at the very edge of the map, to the southwest, right next to the Iron Forest anomaly. A poltergeist is hovering near our target, so we move slowly, as it reacts to the main character's movements. We kill the poltergeist and can search the helicopter. Another cutscene shows Degtyarev (the main character) discovering that the crew of this helicopter died in the air, but the onboard computer has managed to find maps of the area between Zaton and Jupiter.
Tips: Search the nearby corpses of soldiers, collect ammunition, etc. If the poltergeist notices you, it will throw objects. Hide behind corners and various shelters.
Area Maps: Find Interested People
We head to the cargo ship "Skadovsk," speak with a stalker named Pilot, and offer him the maps. He copies them to his PDA. Now we know there's a shortcut between Yanov Station and Skadovsk. We hand over the maps and gain access to a cheap route between locations. The next helicopter is the Skat-3 .
Source: stopgame.ru
See also:
Stalker: Call of Pripyat - Quest "Mercenary Camp"
Stalker: Call of Pripyat - Quest "Tempting Business"
Stalker: Call of Pripyat - Quest "Inaccessible Cache"