What is this RAF biplane, and where was the photo taken (possibly in the 1920s)?
I believe the plane is an Airco DH-9A.

https://en.wikipedia.org/wiki/Airco_DH.9A#Interwar_RAF_service



The location may be Iraq. It looks like the RAF 55(B) Squadron: https://en.wikipedia.org/wiki/No._55_Squadron_RAF#Between_the_Wars.

On another picture I think I recognise the dog on the right in your picture (but now a bit older): https://55bomber.wordpress.com/2010/12/02/raf-55b-squadron-hinaidi-iraq/



Blotto: