The PAC/RATs (Programmed Assault Computer/Rapid All Terrain) are three small unmanned robot weapons systems used by the G.I. Joe team.
These are an early precursor to the modern recon/attack drone program. As drones, they may be programed to a set patrol, or remote-operated by radio. In programed mode, they move and attack within the limit of their programing - usually a set path, and targeting anything without an IFF (Identify: Friend or Foe) signal. In remote mode, they are operated by a RTO specialist or tactical computer. This mode leaves the units vulnerable to enemy jamming or hacking. Each unit has its own remote-control device, but RTO specialists can set their codes into their portable computers.
There are tree types of PAC/RAT systems: a flamethrower-carrier, a quad-Machinegun, and a missile-carrier.
The P.A.C./R.A.T.s were first deployed to stop a large force of Cobra infantry and H.I.S.S. Tanks.
G.I. Joe: A Real American HeroThe P.A.C./R.A.T.s were deployed to stop three Cobra S.N.A.K.E.s from reaching the Palace of Doom. They succeeded and congratulated one another with beeps and whistles. 
G.I. Joe: A Real American Hero (1983)
- Flamethrower: This P.A.C./R.A.T. had three pivoting legs and a large housing for the flamethrower itself. It also featured twin swiveling guns below the flamethrower housing and a separate 'remote control' that could fit in the hand of a G.I Joe figure.
- Machine Gun: This P.A.C./R.A.T. had four machine gun cannons; two facing forward and two that could swivel up and down. The housing for the machine gun cannons could pivot left and right and rested on four wheels. It also came with a faux remote control for a figure to hold.
- Missile Launcher: The Missle Launcher P.A.C./R.A.T. featured four missile in a two-stage rack that sat on a mock-up of a tred track. Like the other two P.A.C./R.A.T.s, it also came with a remote control for use by a G.I. Joe figure.
- Note: All three P.A.C./R.A.T.s were sold in retail stores until 1985. Later on, they were made available in a three-pack via mail-order through Hasbro Direct.
- The "Flamethrower" P.A.C./R.A.T. bears more then a passing resemblance to the Crawler attack drone from the anime Crusher Joe.