A skimmer is a Mogadorian ship that cannot leave the atmosphere, hence the name. They are much like a Human's fighter jet. They are six seaters, and are mounted with many weapons. In The Revenge of Seven, Adam hacks into a skimmer in the Everglades Base and uses said weapons to open fire on a group of Mogs in order to save Six, Marina, and Nine. Six, Marina, and Adam later fly it to the Sanctuary in Mexico. Adam uses the communicator in it to trick some Vatborn scouts in order to get past it.
In The Fate of Ten, Phiri Dun-Ra rips out a piece of the engine in both the Garde's skimmer and all the surrounding skimmers, to prevent them from escaping. After Six, Marina, and Adam capture Phiri, she blows up all the parts to the skimmers, trapping them there. Later, after Sarah arrives with Lexa, Bernie Kosar, and Mark James, they rig the skimmers, including their own, to blow when the Mogadorians arrive. When they do, Mark James blows the skimmers up, the explosions killing at least thirty Mogs, along with many more killed by friendly fire and debris.
According to Adam, skimmers have ejector seats.