MvR on rotary engines

"a letter to Fritz von Falkenhayn. A few days ago I sent you a report about the Rizinus Ersatz relative to rotary engines. I am of the opinion that, owing to the poor oil that is available to us, rotary engines are no longer suitable for this war. Therefore, I set no high value on having rotary engines in my Geschwader, even when they produce 200 horsepower. As the situation is now, I would prefer to have the Fokker with the BMW engine or the supercharged Mercedes. Should the Fokkers be issued with unsupercharged enginges, I would not refuse them. Here there is mostly bad weather and extremely scant enemy flying activity in our Armée sector. Furthermore, I am the leader of four Schutzstaffeln under Hähnelt and no longer Jagdgeschwader-Kommandeur, which after a year and a half of fighter aviation is a change. I do not want it said that the change is excessively interesting. The British are much busier in the 17. and also the 6. Armée sectors than here on our Front. My brother will arrive here tomorrow and is again in good health, as he confirms. He has missed nothing, only some ground support flights, which he would have put up with, but no aerial combat."