If you're talking about the MK1 cowl, the issue is exactly what you
suspect - the limiting factor is how much air you can vent out of the
cowling given that the inlet area and pressure is so very much greater than
the outlet area/pressure. You may find that the NACA duct becomes a hot air
exhaust! (Better to buy a plenum chamber and increase the cowl exit area by
a combination of vents and spacers on the bottom of the cowl in my
experience)
Regards
Roger Mills 141
-----Original Message-----
From: owner-europa@aztec.houxou.com
Subject: Re: Lower cost carb heat solution?
We have adopted your solution in reverse.
This is based on the assumption (which we have been told is correct) that
carb icing in a normal Europa installation is virtually nonexistent due to
the heating in the engine compartment.
We have installed a large NACA scoop in the top of the cowling, operated by
a choke cable. This enables us to introduce cold air (or at least luke warm)
into the area the carb intakes are located. We figured this was a much
cheaper alternative to a plenum chamber and also keeps the regulator box and
electrics cool at the same time.
Till we fly the aircraft we will not know how much air we need to vent out
of the engine compartment to ensure a good airflow through and past the
carburettors. We figure the removal of the hot air is as important as
introducing cooling air at the front.
Carl Pattinson
G-LABS
----- Original Message -----
From: "David Cripps" <david.cripps@spsystems.com>
Subject: Lower cost carb heat solution?
Although the carb heat system from Skydrive is very good, it is quite
expensive (c200).
Would it work to divert the hot air from the cockpit heating system into the
plenum chamber, via a simple valve such as the cockpit heating system
already uses? I know this would affect the engine performance in the same
way as the application of carb heat does on 'normal' aircraft, when it feeds
hot air through the carbs, but it might be a very cost-effective way of
dealing with icing if it arose?
Any thoughts? Maybe someone's done this already?
David
GBWJH
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