The automatic surface to air missile launchers a.k.a. SAMs are anti-aircraft weapons in Just Cause (1).
They are surface to air missile (link to wikipedia) launchers.
Until a base belongs to the government, those missile launchers will try to kill Rico, if he approaches with a flying machine. As soon as a base is taken over by the Guerrillas, they start shooting at any government aircraft in range.
If you have Heat, all vehicle weapons will automatically lock onto the missile launchers, just like they would to any other enemy. Oddly enough, your weapons will still lock onto them during heat, if you approach a friendly military base.
The missile launchers look like boxes that have 4 missiles connected to either side and a small radar antenna on the top.
They are installed in many different locations. The ground positions are usually surrounded by a low wall of sandbags. Many are on the tops of purpose-built wooden towers. Two are on a train. Three are on a ship.
Those wooden towers all have ladders leading to the top and at least two of them can be found in civilian use, as observation towers. One is north north-east of "Guerrilla 23 Camp soledad" safehouse. Perfect for BASE jumping.
At least one of them can be seen in almost every military base (there's only about 3 military bases that don't have them).
- Almost every military base.
- On 3 of the corners of the fortress on Isla San Cristobal, located north-east of "Guerrilla 06 Camp Contrabandista" safehouse.
- In front of the presidents palace on Isla Dominio (south-east corner of the map).
- On top of the mountain on Isla Dominio.
- Hidden between the trees on a hill, just north north-east from the airfield on Isla Dominio.
- At a radio station, during the mission Broadcast News.
- On a train, in the mission Guadalicano Choo Choo.
- On Salvador Mendozas un-named destroyer, in the mission Sink the Buccaneer.