After an RAF grave had been identified and registered by an Army Graves Registration unit, a temporary wooden (or sometimes steel) cross was erected.
Coates crew grave marker. Courtesy of David Chapman.
If the grave was a communal one because the inhabitants of it had not been individually identified, a communal marking was made.
The picture above of the communal marker for the Coates crew in Woensel Cemetery, Eindhoven, Holland, was taken before the Imperial War Graves Commission replaced the temporary wooden crosses with the permanent headstones that give the cemetery such a different appearance today.
The Coates crew were members of 97 Squadron of THE PATHFINDERS – they were all killed on 25 March 1944 after their Lancaster was shot down.
Before the permanent gravestones were erected, RAF Missing Research officers had managed to identify all the crew individually except William Chapman and John Baldwin, who today share a joint tombstone with the intertwined insignia of both the RCAF and the RAF.

Joint grave for Baldwin and Chapman, December 2014. Courtesy of Glyn Elston.
Notifying the Coates family in 1946 of the confirmation of the crew’s grave, the Air Ministry Casualty Branch told them it had been established by means of a signet ring and the number on a piece of aircraft wreckage.

Coates crew graves in December 2014. Courtesy of Glyn Elston.