Osterkamp and the unknown allied unit..?

[Soderbaum]

Hi

I have tried the following question before with negative result.. >

On 16 September 1918 was Osterkamp flying alone a long way inside over allied lines over Flanders..

Near the allied aerodrome Furnes he could completely undiscovered attack two allied Sopwiths-1s and was able to quick shot at one which directly collided with the other Sopwith. Both hostile aircraft was reported by him to fall and crash into ground..

After the success he was jumped on by a group of 18 Sopwiths-1 ...but as always Theo was lucky and was able to return to own lines where the enemy aircraft stopped following him..

I wonder if anyone knew what possible allied units which were stationed at Furnes at this time..?

Possible the Furnes airfield were occupied by Belgian and perhaps French units..?

Another German source identify the first two Sopwiths-1s as Sopwith Dolphins which could indicate that they also could be Spad-1s..

For an help thank in advance

Gunnar