De Havilland DH.9
Immediately after the First World War, De Havilland supplied at least 20 DH.9's to the Aviation Militaire Belge. In the period 1922-23 Sabca produced another 30 aircraft for the military. Precise details on the exact number of aircraft supplied to Belgium or constructed under license by Sabca is still subject of discussions but registrations up to D-101 have been noted on available photographic material. Many sources talk about 103 DH.9's used by the Belgian military. De Havilland DH.9's were used by the N° 1 ..
http://www.belgian-wings.be/ The Belgian Aviation reference site