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Date: Fri, 21 Oct 2005 13:08:32 -0400
From: Ernest Christley <echristley@nc.rr.com>
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To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] Re: NACA scoops
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jesse farr wrote:

> Ernest: On a delta, surely there is plenty of room in front of your 
> wheel/tire combinations to mount radiators in wing strake  leading 
> edge. What is wrong with that?
> jofarr, soddy tn
>
Nothing 'wrong' with it.  Just all those compromises again 8*)

A duct behind the wheel well offers the advantage of:
-the space Kelly is referring to is the baggage compartment.  A 
sufficiently sized duct eliminates a large portion of the baggage capacity.
-a more favorable CG benefit by moving the radiators and duct further 
aft.  Leads to less trim drag.
-the wheel wells are very dirty aerodynamically.  I've been hoping to 
fold the wheel well drag into the cooling drag (two birds, one stone)
-I was hoping that extra airflow through the duct and exiting just 
before the trailing edge would push back the elevon washout point, 
providing more authority for a slower landing.
-lack of complicating aircraft structure (I'd have to remove one rib 
tie) would allow for a self-contained, fiberglass duct that would bolt 
up from the bottom and drop down to the ground for 
servicing/inspection/redesign.

Kelly's proposed placement has the advantage of:
-putting the entrance directly into the propwash
-possibly combining the entrance step with the cooling intake, 
eliminating at least one external 'appendage'
-taking cabin heat directly off the cooling radiator with a very simple 
duct extension
-shorter coolant lines
-very solid mounting options in the form of the Station 3 Extension, 
which is 5/8x.035 4130 tube (the rear mounting proposal relies on the 
much less substantial 3/8x.035 tube rib  and .020 stainless steel sheet 
metal rib struts for support).
-a correctly designed exit would hopefully push back the stagnation 
point on the top surface of the fuselage, leading to better cruise speed 
and efficiency

Will reduction in wheel well and trim drag trump moving the stagnation 
point?  Will the addition of another 8 to 10ft of 1" tube filled with 
coolant change the equation to a great extent?  Does the ability to 
remove and easily build a new and improved duct offer more advantage 
than quick and easy cabin heat? Will Rachel learn here lesson and 
finally leave Edwardo?

For these answers and more, tune in next time to...

"As the Spinner Turns"
<queue closing theme music>

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