Comments by "Be Kind To Birds" (@BeKindToBirds) on "AIR COOLED vs OIL cooled vs WATER cooled ENGINES" video.

There is a point in which oil is no longer sufficient for cooking either. After that the most common method is liquid cooling with the fuel. This is jet and rocket territory now but most turbines have a cycle to bring fuel through the engine to cool the turbine as well. Mainly again, in very very powerful turbopump engines and the like. Well past oil at that power level.
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