Nieuport 11. Part one. The 'Bébé' in Belgium

 

The Nieuport 11 was a French sesquiplane fighter aircraft from the World War I, while the Nieuport 16 was an improved variant, powered by a more powerful Le Rhône engine.
It received good reputation and was exported to various countries around the world, among them, Belgium.
In contemporary sources it's referred as 'Nieuport XI C.1' (or 'Nieuport XVI C.1) where the letter 'C' stands for 'Chasseur', meaning 'Hunter' in French.
It's commonly believed that approximately 12 Nieuport 11 C.1 were sent to serve with the Belgian Aviation Militaire (Belgian Military Aviation) on 5th January 1916 and were followed by two additional Nieuport 16 in September 1916. 
Both Nieuport 11 and 16 were employed by the Belgian Military Aviation's fighter squadrons, Nº1 (Chardon) and Nº5 (Comet), and were even employed by some famous aviation pioneers like Jean Olieslager or Egide Roobaert (who was among the first to have used the Le Prieur rockets -the very first air-to-air rockets), until they were replaced in frontline service by either the better Nieuport 17 or the Hanriot HD.1. 
The remaining Nieuports 11 or 16 were used for pilot training purposes at the Belgian schools of Étampes (France), Juvisy-sur-Orge (France) and after the war, at Asch (Netherlands). 
The last Nieuport 11 or 16 was withdrawn from Belgian inventory in the early 1920s.

Sources:
1st https://www.belgian-wings.be/nieuport-11-c1-16-c1
2nd en.wikipedia.org/wiki/Nieuport_11
3rd https://en.wikipedia.org/wiki/Nieuport_16
4th Aeronaut Books - The Belgian Air Service in the First World War