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Some extremely simple models for a base of "Eagle" ships from "Space 1999", made entirely with parts from the basic "Town" sets of the early 1970s (the Space sets hadn't come out yet!).
We used to have a blast building fleets of these, having wars, smashing them up, and re-assembling them. Wheeled vehicles ("Track-Attackers") can be carried underneath, then released to drive around on the ground. With a fleet of Eagles and a control tower, you have a complete Eagle base!
I entered these into MLCad purely from memory...I still remember the designs perfectly ~32 years after originally building them.
Here instructions for the Eagles and base, in JPEG format: (1.4 MB ZIP).