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Date: Fri, 10 Mar 2006 08:23:35 -0700
From: Bob White <rlwhite@comcast.net>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] Re: NACA's, Cooling and Sport Aviation Mag..
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Hi Buly,

I'll have to look into that.  There is a vent in the rear baggage
compartment that would let air exit out the rear of the fuselage.  There
is also a round Plexiglas vents in each front side window that can be
turned to input or exhaust air.

Bob W.


On Thu, 9 Mar 2006 23:18:34 -0500
Bulent Aliev <atlasyts@bellsouth.net> wrote:

> Bob, if the cabin does not have exhaust path for the incoming air,  
> the cabin pressure will build up and the NACA scoops will be  
> ineffective.
> Buly
> 
> 
> On Mar 9, 2006, at 10:00 PM, Bob White wrote:
> 
> > I'll add a comment that may or may not have any relevance.  I have
> > NACA ducts on the side of my plane that are used for cabin cooling, so
> > no real back pressure to speak of.  The original builder told me they
> > worked marginally for that.  They would sometimes flow OK, and at  
> > other
> > times not at all.  I suspect that if the plane were flown slightly
> > uncoordinated, one side or the other might be blanked in the position
> > they are in.  This might be less of a problem on "rounder" surfaces
> > but does seem to indicate some sensitivity to getting the installation
> > right.
> >
> > Bob W.
> >
> >
> > On Thu, 9 Mar 2006 21:25:33 -0500
> > "Ed Anderson" <eanderson@carolina.rr.com> wrote:
> >
> >> I was a bit disappointed in the article, myself.  For instance his  
> >> insistence about adhering to no more than a 7-14 deg slope for the  
> >> diffuser is the number NACA found to be best for wind tunnels.  He  
> >> makes no mention of many other types of diffusers (such as the  
> >> streamline duct with a measured (laboratory) pressure recovery of  
> >> 84% and can have slopes of divergence approaching 65 deg near the  
> >> cooler core).  Almost appears as if he had never heard of K&W.    
> >> On the other hand, perhaps for air cooled engines, he may not be  
> >> that far off.  The fins on the jugs of air cooled engines may not  
> >> offer as much back pressure as say a radiator which may make the  
> >> NACA duct work better.
> >>
> >>
> >> However, there is a NACA publication on NACA ducts and here is a  
> >> brief extract on their conclusions about its use
> >>
> >>
> >> Does not say they can not be used for radiators, etc, but  
> >> apparently they felt not the best choice for those applications.   
> >> Note it qualifies this conclusion a bit by referring to all
> >> flight conditions.  Does this imply that if you selected A flight  
> >> regime (say cruise) to optimize for, that it could be make to work  
> >> fine there?  Don't know, so many questions, so little time. {:>)   
> >> I personally tried a NACA duct early on trying to solve my oil  
> >> cooling problem, didn't work for me - but, it was probably not a  
> >> fair test as I had other problems than just pressure recovery {:>)
> >>
> >> Anyhow, my $0.02 on the topic.
> >>
> >> Ed
> >>
> >>
> >>
> >> ----- Original Message -----
> >> From: "Bill Dube" <william.p.dube@noaa.gov>
> >> To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
> >> Sent: Thursday, March 09, 2006 8:58 PM
> >> Subject: [FlyRotary] Re: NACA's, Cooling and Sport Aviation Mag..
> >>
> >>
> >>> I read that article as well. I had the same skepticism about the  
> >>> NACA
> >>> intake for cooling. My understanding is that with an NACA inlet, you
> >>> don't get the ram pressure you need to force air through a high
> >>> fin-count radiator. Am I wrong about this?
> >>>
> >>> Bill Dube'
> >>>
> >>> David Staten wrote:
> >>>
> >>>> At the risk of invoking PL's name, anyone else read this months  
> >>>> Sport
> >>>> Aviation mag from EAA, and notice an article on cooling that  
> >>>> seems to
> >>>> indicate that NACA's are acceptable and adequate for aircraft  
> >>>> cooling
> >>>> needs? I have no idea regarding the authors credentials, and I no
> >>>> longer monitor PL's "newsletter".. I was curious more than anything
> >>>> else... Pauls reaction, others reactions, etc.
> >>>>
> >>>> Translation.. yes.. I'm stirring the pot/Trolling... I figure if we
> >>>> are using NACA's on the Velocity, that makes us somewhat of a NACA
> >>>> supporter..
> >>>>
> >>>> Dave
> >>>>
> >>>> -- 
> >>>> Homepage:  http://www.flyrotary.com/
> >>>> Archive and UnSub:   http://mail.lancaironline.net/lists/flyrotary/
> >>>>
> >>>
> >>> --
> >>> Homepage:  http://www.flyrotary.com/
> >>> Archive and UnSub:   http://mail.lancaironline.net/lists/flyrotary/
> >>>
> >
> >
> > -- 
> > http://www.bob-white.com
> > N93BD - Rotary Powered BD-4 (first engine start 1/7/06)
> > Custom Cables for your rotary installation -
> > http://www.roblinphoto.com/shop/
> >
> > --
> > Homepage:  http://www.flyrotary.com/
> > Archive and UnSub:   http://mail.lancaironline.net/lists/flyrotary/
> 
> 
> --
> Homepage:  http://www.flyrotary.com/
> Archive and UnSub:   http://mail.lancaironline.net/lists/flyrotary/


-- 
http://www.bob-white.com
N93BD - Rotary Powered BD-4 (first engine start 1/7/06)
Custom Cables for your rotary installation -
http://www.roblinphoto.com/shop/