Jay wrote:
From what I understand, the low power to weight ratio of diesel
engines has been the main limiting factor for their adoption into
small planes (and passenger cars for that matter). The reason for the
high weight as it was explained to me was that the high compression
used for an auto-ignition type engine required strong, and thus heavy
castings to withstand the pressures.

So these days you see diesels fitted with forced induction systems,
which apparently makes them more peppy (e.g. the 90hp VW 1.9L TDI).
But doesn't this more powerful charge being introduced by the forced
induction system, just require again, a heavier engine to withstand
the more powerful explosion? Or to put in in converse, if the same
engine could have withstood the more powerful charge, couldn't they
have built it lighter in the first place and used a conventional
induction system? For now lets ignore the altitude power
normalization aspect for aircraft operation.

Having spent years behind the big wheels, power to weight is probably on
the bottom of my list for not having a diesel in a small vehicle of any
type.

Your burning kerosene there, so the pistons have to take their time to
give those long carbon chains time to burn down. The engines I sat on
top of usually ran between 1800 and 2100 RPM, were slow to rev up, and
shook like a crack whore. Anything that shook like that would tear an
airplane apart, and would be very uncomfortable in a passenger car.

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"Ignorance is mankinds normal state,
alleviated by information and experience."
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