|For the alien crash site in Fallout 3, see alien crash site.|
When traveling around the Commonwealth after reaching level 20, a random encounter may occur, where the Sole Survivor hears the sound of an incoming plane. A vessel will then pass quickly by overhead before crashing in the distance. It leaves a distinct trail of smoke. The ship always crashes in the same location, and one can hear the explosion from far away.
Alternatively, if the Sole Survivor activates relay tower 1DL-109, a radio signal titled "garbled radio beacon" will be discovered. If they tune their radio to the frequency, they can travel east and the signal will resolve to a higher quality until they discover a crashed alien vessel.
The site features a half-buried UFO in a hillside with a skid area of destruction including broken trees, flattened ground and scattered flames. The surrounding trees will be permanently on fire, making the location easier to spot from afar. There is no way to enter the UFO, nor anything to scavenge at the crash, but next to the still burning UFO is a trail of green blood. The Sole Survivor can follow the trail slightly north, down into a ravine and then into a nearby unmarked cave.
Inside the cave is an alien with an alien blaster pistol and 181–441 alien blaster rounds. If the alien is targeted in V.A.T.S., it will show that its right leg is crippled. On sight, the alien will immediately attack the Sole Survivor. Next to the alien is a human skeleton and a ham radio which is the source of the nearby garbled radio beacon. Turning the ham radio off will disable the beacon.
- The UFO crash can be witnessed as far away as the Museum of Witchcraft.
- The trail of debris at the crash site indicates the ship hit the ground while traveling northwest but the smoke can be seen from any direction.
- If the player character is traveling with a companion, they will say something as the ship flies overhead.
- The player character cannot pacify the alien with the Wasteland Whisperer perk.
- Prior to the crash, the trees in the area already appear burned and several mole rats may be present. A skeleton on a sleeping bag, crushed by a fallen tree, can be found at the location. Alongside the skeleton is a burned book, eyeglasses and a metal box containing assorted loot.
- The green blood trail on the floor may disappear once the alien is encountered in the cave and killed.
The UFO crash site appears only in Fallout 4.