I’ve was reading about Dr1’s and came across an interesting fact. It seems most Dr1’s were built with the 110 hp Oberursel UR III engine. The “Top Aces” flew the 110 hp Thulin LeRhone 9J engine. Since both are 100 hp engines what was the major difference?
The two engine designs were identical. Which one happened to be available was a significant factor in which one was used. I’m not certain but I think the Thulin version was more reliable due to better manufacturing.