Hello John,
I have been able to identify one of the pilots in your photograph.

His name is Harold Hemming, Worcs. Rgt., R.F.C. & R.A.F.
He started out as an observer before training as a pilot (1916).
He was awarded the Air Force Medal in 1919.

He served with the R.A.F. into the 1920’s.

His larger than usual R.A.F. service record is on Find My Past.

He had an interesting life. From afleetingpeace.org

Major Harold Hemming, Air Force Cross
Director (with Alan Butler as Chairman) of the ‘Aircraft Operating Company’. In 1925, they were air surveying in British Guiana.
In 1923, he flew Alan Butler’s DH37 ‘Sylvia’ in the King’s Cup, coming 5th (as had Alan himself, the year before), and then borrowed it again in 1925, coming 3rd.
Unfortunately, while he was making a test flight in 1927 in the DH37 (now re-engined and called ‘Lois’) the aircraft hit a scoring board and crashed. The passenger was killed and Hemming lost an eye and sustained other injuries.

All the best.