Phantoms is a set of free wargames rules based on the old Avalon Hill “Mustangs” game. It’s for playing air combat games from 1960 to present. The link is to the deluxe version with all of the updates, data cards and scenarios.
Rules: Aircraft
Vietnam Air Fury Rules
Vietnam Air Fury is a set of air combat rules based on the earlier Space Fury Rules.
Air War 1917
Air War 1917 is a barebones — and free — version of Wessex Games’ AirWar: 1918 biplane combat rules.
MIG Alley Ace
MIG Alley Ace are rules for modern aircraft combat from 1945 to the missile age.
Flying Circus WWI Air Rules
Flying Circus is a set of free wargames rules based on the old Avalon Hill Mustangs game.