In February 2015 I received the following email from Simon Gray:
In case you are interested in identifying individuals in this photo, my grandfather is 3rd from left in the back row. He was a 2nd Lieut Observer, but not for long as he was invalided out due to severe air sickness, and transferred to an infantry regiment. Details below, from this pdf (National Roll of the Great War). After the war he worked as a dentist. He died in 1973. One of his sons (my uncle) also served in the RAF.
My thanks to Simon Gray for this information.
Peter Facey, Winchester, England
20150209 originated