Scanned from a print in the 1969 book "The great air war", original photo 1917/18
The front gunner in a German Gotha bomber
The Goth entered service in mid 1917 and remained in service till the end of the war, it had a service ceiling of 6,500m (21,300ft) which required the crew to use oxygen tubes. the gunner can be seen holding the tube in his mouth
US War Dept. photo