REFLECTOR: NACA Outlet

Chuck Jensen cjensen at dts9000.com
Tue Jul 1 07:36:05 CDT 2008


The new issue of Central States Association (CSA) newsletter has a few page article on installing a P-51 scoop on a Long by Schubert.  The design factors and test data was interesting stuff and would certainly be of help to someone looking at the issue of NACA vs. Scoop.

Chuck Jensen


-----Original Message-----
From: reflector-bounces at tvbf.org [mailto:reflector-bounces at tvbf.org]On
Behalf Of Dave Philipsen
Sent: Tuesday, July 01, 2008 1:47 AM
To: Velocity Aircraft Owners and Builders list
Subject: Re: REFLECTOR: NACA Outlet


There was a good seminar at Oshkosh last year by Terry Schubert and Gary 
Hertzler regarding cooling, scoops, etc.  They both have much experience 
in cooling and drag reduction.  The seminar stated that NACA scoops do 
NOT make good outlets.  They also stated that outlets should not be 
perpendicular to the airflow because of excessive drag.  In fact, they 
even stated that a NACA scoop, while very efficient for some things, is 
not the best idea for oil coolers.  The seminar mentioned that 
Velocities get away with the NACA inlet for oil coolers because the 
scoop is usually in a high-pressure environment and the air is forced in 
by brute force.

I am not saying that the NACA scoop is wrong but these guys are 
considered the gurus when it comes to this stuff.  I believe they have 
both set fuel efficiency records in their Long-EZs of which they each 
have 3000+ hours in type.  I can send you the zip file containing the 
seminar in Power Point and MP3 format if you like.  Your mail server 
would have to be able to accept a fairly large attachment though.

Dave

Jack Prock wrote:
> I know a NACA scoop inlet is the best for least resistance for an inlet, I
> am wondering what the best way
> is to have an outlet. I am building the oil cooler in the nose and making
> the outlet on the bottom of the fuselage.
> Is there a NACA outlet? Is it best to just have a rear facing pipe? Or a
> hole in the fuselage that air get pumped out?
> Does it matter? I would think that any air flow perturbations would cause
> drag? Anyone have any thoughts on this?
>
> Jack Prock
>
> _______________________________________________
> To change your email address, visit http://www.tvbf.org/mailman/listinfo/reflector
>
> Visit the gallery!  www.tvbf.org/gallery
> user:pw = tvbf:jamaicangoose
> Check new archives: www.tvbf.org/pipermail
> Check old archives: http://www.tvbf.org/archives/velocity/maillist.html
>   

_______________________________________________
To change your email address, visit http://www.tvbf.org/mailman/listinfo/reflector

Visit the gallery!  www.tvbf.org/gallery
user:pw = tvbf:jamaicangoose
Check new archives: www.tvbf.org/pipermail
Check old archives: http://www.tvbf.org/archives/velocity/maillist.html



More information about the Reflector mailing list