This is true. My pilot just found that out first hand. A simple patrol way, way behind friendly lines at 2300 m. Spotted the Hun way, way above. Didn't think we'll ever get him. Wasn't even sure Morane could fly this high. We finally got up to 200 m below him, but he knew what he was doing. He stayed just high enough out of range and I struggled to keep up with him without stalling - my wingman did jut that and ended some 500 m below us. He eventually caught up with us. Meter by meter we went higher and higher and eventually got in range. My observer almost emptied the entire supply of ammunition (60 rounds left), but we got him. Now I'm just waiting for the confirmation from the CO.
"Take the cylinder out of my kidneys, The connecting rod out of my brain, my brain, From out of my arse take the camshaft, And assemble the engine again."