Belgian aircraft data is scarce and incomplete. The following chart indicates when a certain type was in use, based on various sources, including biographies of individual aces. It does not show how many of each aircraft was in service at any one time, but it is hoped that it will be useful in planning historically plausible scenarios.
There is some uncertainty around exactly which aircraft were in use in the Belgian escadrilles. It is known however that all 3 Belgian fighter squadrons were equipped with Nieuports when first formed and all were flying mainly if not exclusively Hanriot HD.1s by the end of the War.