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Aircraft general knowledge

The diesel engine has a gearbox that reduces 4400 RPM to 2200 RPM. This makes

the engine quiet, and it also uses less fuel, about 30%, and since diesel is also

cheaper than gasoline, the diesel engine is somewhat cheaper in fuel than the

gasoline engine.

8.10.2 Diesel engine vs. gasoline engine

But you don't just replace your gasoline engine with a diesel engine.

The first engine replacement will run up to about 600,000 DKK due to conversion,

so it is a serious expense.

When you come with a "direct drive" engine that runs at 2500 RPM, it is easier
to convert to a diesel engine.

In addition, the weight is reduced.

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8.10.3 Turbocharged engine

A regular aircraft engine loses power with increasing altitude. In order to

maintain the engine's performance with increasing altitude, it is necessary to
supply engines that need performance at higher altitudes with a turbo.

As shown in the figure, an air pump
(turbocharger) is mounted in the

engine.

The turbocharger is driven by air

from the exhaust system.

Flyveteori PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 753