Nigel Graham a crit :
> I would be very interested to hear how successful this is once fitted
> and tested (either on or off list).
> With regards to oil over-temp should the water coolant be lost, I
> think you might be surprised how resilient a modern full-synthetic oil
> is (which can be used in a 9 series engine as long as you don't run
> 100LL). On a reduced power decent I think you would get away with it.
Nigel and all,
I respectfully beg to differ with the above statement.
As some listers here may know I've been conducting extensive oil and
water cooling tests on a 914.
Whereas in-flight heat rejection through oil and water actual numbers
are not totally in agreement with the Rotax ground bench numbers, the
coolant plays a key role, and total loss of coolant is definitely a
major issue. I seriously question the chances of engine in-flight
survival for more than a very short time at idle.
If you happen to have solid data on experiments on Rotax engines with
partial or total loss of coolant I would be much interested and willing
to publish them on Contrails !
Concerning the coolant thermostat option, the question is, do you value
lightness, simplicity and low drag or not ?
And above all, do you have ample cooling, since the idea is to always
provide excess cooling and just throttle the oil flow to help oil
warming up.
A thermostat helps oil *warming*, not cooling, at the price of
additionnal weight and constant cooling drag penalty.
As I understand that some Europa builders experience marginal cooling,
they may wish to first fix the cooling airflow issue.
FWIW,
Best regards,
--
Gilles
http://contrails.free.fr
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