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some diesel powered airplanes in WW-2 Germany.If you want to stay up more than about 3 hours, the weight of the fuel exceeds the weight of the engine. Then you want to think if another engine, even of more weight, will save enough fuel to reduce total fuel+engine weight.
I think many or most air-ships ran Diesels. I'm sure of the Beardsmore Diesels in the English airship program. (They get a lot of space in engine books because they look good, but were troubled.)
Then there is the
Packard Diesel.
As you know most Diesels are like spark-engines with separate intake and exhaust valves and manifolds. Spark engines usually inhale fuel/air mix which must be kept away from exhaust. One carburetor for several cylinders. Air-filter. And on the other end, a muffler.
The Packard had one valve per cylinder. Intake and exhaust in the same place. No manifold. Why not? The Diesel intakes plain air, which it can get anywhere. Exhaust is violent and throws the smoke out far enough the next intake is not contaminated. No air-filter, no muffler.... on the ground we need air-filters but not when we leave the ground. Mufflers are often dispensed with in aircraft.
It ran well but IIRC was never designed into anything.
The killer flaw seems to be that high-altitude was becoming popular (or essential) and there's no good way to blow an engine of this construction. (Also the guy who championed it was killed.)
The Packard Diesel held the nonstop no-refueling endurance record (84.5 hours) for 55 years. Was beaten by Rutan's Voyager's 216 hours. Note that Voyager was super-special while the Packard was in a 5-passenger Bellanca CH-300.