Carl,
Assuming you're talking about a classic cowl, I would strongly advise
against providing just a NACA duct - you need an enclosed plenum box to
isolate the intake from the hot air in the cowl and provide cold air to the
carbs. If you measure the high pressure inlet area and compare it with the
available outlet area you will see that a simple NACA duct in the top will
be ineffective due to the pressurised hot air in the cowl (- it may even
provide another exit path?).
The factory plenum mod works well - why invent it again?
Regards
Roger Mills
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-----Original Message-----
From: owner-europa@post.aviators.net
Subject: Europa mods
I need some help with getting my mods PFA cleared and I have been told the
best way is to find someone else who has done my mod (or rather find someone
who's mod I have done). At present I am working on
(1) Navaid wing leveller and
(2) tail fin strobe attachment (mounted on top)
(3) NACA scoop on top of engine cowling to indcrease cold air to carbs
(scoop is operated via a choke cable - operating against a spring. There is
no plenum box just a scoop in the centre of the cowling.
Does anyone have a PFA number no for their mods (assuming they are similar
to mine) that I could quote when applying - I will need details of the mod
to confirm that it is similar.
I enclose a photo of my leveller mod. The tailfin mod should be self
explanatory ( I know its a common mod). Not sure about NACA scoop mod.
Thanks in anticipation
Carl P
I have already sent this to the Europa group but it seems that postings
with attachments dont get through. This one is minus the photo. If yu are
interested and need to see the mod I am referring to email me and I will
send attachment by return (but not via europa@avnet.co.uk)
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