French-built aircraft used by the US Army Signals Corp for artillery spotter training with the 5th Artillery Observation School. Photo from: National Archives at College Park, Maryland

This Sopwith 1 1/2 strutter is seen in the marvellous Musee de l'Air et de l'Espace. I had last seen this aircraft in 1975 when it had been on display at Chalais Meudon. It was built in 1917

This fighter type was also known as the "Sopwith 1 1/2 Strutter".

The 1A2 was a French-built reconnaissance version of the Sopwith 1½ Strutter. Over 4000 Strutters were produced in France during World War I.

This aircraft, built in 1917, was seen at the Musee deL'Air collection at Chalais Meudon before the collection moved to Le Bourget. It was basically unrestored and looked better for it. I am uncertain whether the markings are French or British.