Billy was sent out alone to attack an enemy RR yard and destroy as much of the supplies in transit as possible. Just a short hop to the north of Toul. He ran into a lone Alb DVa on the way there, well almost right above RR yard.
Billy figured it was a an injured craft heading to Thiacourt, the closest enemy airfield. Nice earth tone paint job on the Hun's Albatros.
One Hun down and on the RR Yard goodies. Crates and barrels of fuel were his targets and set over a handful of them afire before taking a few hits from a machine gun and RTB.