Return-Path: Received: from scaup.mail.pas.earthlink.net ([207.217.120.49] verified) by logan.com (CommuniGate Pro SMTP 4.2b8) with ESMTP id 325792 for flyrotary@lancaironline.net; Sun, 18 Jul 2004 19:27:26 -0400 Received-SPF: pass receiver=logan.com; client-ip=207.217.120.49; envelope-from=sqpilot@earthlink.net Received: from user-33qt52m.dialup.mindspring.com ([199.174.148.86] helo=Carol) by scaup.mail.pas.earthlink.net with smtp (Exim 3.33 #1) id 1BmL3T-0005lq-00 for flyrotary@lancaironline.net; Sun, 18 Jul 2004 16:26:52 -0700 Message-ID: <01da01c46d1e$ac196b50$0000a398@Carol> From: "sqpilot@earthlink" To: "flyrotary" Subject: Fw: [FlyRotary] Re: New Scoop Date: Sun, 18 Jul 2004 18:26:35 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_01D7_01C46CF4.C2385BF0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2741.2600 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2742.200 This is a multi-part message in MIME format. ------=_NextPart_000_01D7_01C46CF4.C2385BF0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable ----- Original Message -----=20 From: sqpilot@earthlink=20 To: Rotary motors in aircraft=20 Sent: Sunday, July 18, 2004 5:55 PM Subject: Re: [FlyRotary] Re: New Scoop Hi, Ed.....The statement I made regarding NACA ducts not working for = carburetors is on the page that you submitted, from NACA....the same one = that says they won't work for radiators, it also includes carburetors in = the same sentence. I agree, Ed....we are finding ways to "make things work" through = determination (sometimes stubborness as in my case), and refusing to = take NO for an answer, just like Columbus, Orville and Wilber, etc. = Scientists also said that the bumble bee is too heavy to fly, given it's = wingspan, etc. Fortunately, no one has told the bumblebee. We have been = told that EWP's won't work, NACA ducts won't work for radiators, etc. = Fortunately, we are using them anyway. We are fortunate to have an = engineer such as yourself on this site, and one that is willing to = listen to evidence from the field as well as numbers and formulas. A = Cozy builder named Al Wick has a Subaru powered Cozy with his radiator = behind a NACA duct, and he can do full power climbs to altitude with no = cooling problems. I copied his installation. (A google search will = reveal his website). Thanks again for all of your contributions to this = site. Paul Conner ----- Original Message -----=20 From: Ed Anderson=20 To: Rotary motors in aircraft=20 Sent: Friday, July 16, 2004 6:50 PM Subject: [FlyRotary] Re: New Scoop I would not argue with your assessment, Paul. I mainly put it up so you folks could see the source that many = "experts" use to tell you "Dummies" why what you have working - can't = possibly work {:>). I was offering a hypothesis as to why in some cases = the results "in-the-field" might be different from what NACA found in = the wind tunnels. I had not heard about the NACA supposedly not being = good for carburetors. My impression was that so long as there was not = back pressure (such as a cooler block will produce) anything that = created a lower than ambient pressure region behind the NACA duct (such = as engine intake or duct into a cabin) would cause it to work OK. I = know that the NACA duct that feeds cooling air into my cabin always has = a tremendous rush of air coming through it. Have to keep it closed off = most of the time at altitude or freeze my butt. Ed Ed Anderson RV-6A N494BW Rotary Powered Matthews, NC ----- Original Message -----=20 From: sqpilot@earthlink=20 To: Rotary motors in aircraft=20 Sent: Friday, July 16, 2004 6:45 PM Subject: [FlyRotary] Re: New Scoop Hi, Ed.....I am of the opinion that the NACA report you provided is = old and out of date. Note that they also state that the NACA duct does = not provide desireable recovery characteristics for carburetors on = reciprocating engines. Tell that to the many LongEZ builders (myself = included) that found it to be very efficient in supplying air to our = carburetors in all attitudes, from cruise attitude to steep climbouts. = They came up with a very nice, low drag inlet, but I don't think they = spent as much time studying their creation or finding out it's true = potential. Just my experience, based upon a very succesful NACA duct = feeding my MS carb on my Lycoming (ugh, sorry about that) powered = LongEZ. Paul Conner=20 ----- Original Message -----=20 From: Ed Anderson=20 To: Rotary motors in aircraft=20 Sent: Thursday, July 15, 2004 6:52 PM Subject: [FlyRotary] Re: New Scoop Looking at John's cooling set up, it appears that the cooler core = exits are in an excellent position to benefit from any lower pressure = region that may exist at the rear of the canard fuselage. =20 Its been my contention that this is one of the reasons that at = least some canard installations appear to defy both the conventional = "wisdom" and the NACA admonishment that NACA ducts are not well suited = for radiator cooling (or other uses that produce a back pressure). That = is - as in John's case - the successful arrangement appears to = minimized the back pressure across the core and perhaps benefits from a = localized area of lower than ambient pressure. Attached is an extract from a NACA report which makes it clear, = that at least in their opinion at the time, the NACA ducts were not = suited for radiators. But, as John and other's have shown, they can = work very effectively. So something they are doing must be different. = The only thing I can come up with is that the canard arrangement = provides the opportunity to benefit from what must be a lower pressure = area behind the fuselage as it moves through the air. =20 However, in my own personal experience in using a Naca duct in = the front of my cowling (in one of my five attempts to solve my oil = cooler problem) the results were consistent with the NACA assessment. = It was not successful for me. One of the differences is my oil cooler was approx 10" from the = firewall and did not have exit to a negative pressure area. In fact, the = pressure inside the cowl was probably slightly positive. I don't know = that would have made a difference but seeing the success of John and = others with it, I am led to believe that having the back of your cooler = cores in a lower pressure area will enhance the probability of success = in using a NACA duct. =20 My 0.02 worth. Ed Ed Anderson RV-6A N494BW Rotary Powered Matthews, NC ----- Original Message -----=20 From: John Slade=20 To: Rotary motors in aircraft=20 Sent: Thursday, July 15, 2004 6:48 PM Subject: [FlyRotary] Re: New Scoop >I believe that his cowling must extend down approximately 4-5 = inches to achieve that. Nope. The cowl is level with the fuselage floor, then curves = upwards. It's tight, but it can be done. John Slade (Got my EM2 .... manual) ------------------------------------------------------------------------ >> Homepage: http://www.flyrotary.com/ >> Archive: = http://lancaironline.net/lists/flyrotary/List.html -------------------------------------------------------------------------= - >> Homepage: http://www.flyrotary.com/ >> Archive: http://lancaironline.net/lists/flyrotary/List.html ------=_NextPart_000_01D7_01C46CF4.C2385BF0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
 
----- Original Message -----=20
From: sqpilot@earthlink
Sent: Sunday, July 18, 2004 5:55 PM
Subject: Re: [FlyRotary] Re: New Scoop

Hi, Ed.....The statement I made = regarding NACA=20 ducts not working for carburetors is on the page that you submitted, = from=20 NACA....the same one that says they won't work for radiators, it also = includes=20 carburetors in the same sentence.
      I agree, = Ed....we=20 are finding ways to "make things work" through determination (sometimes=20 stubborness as in my case), and refusing to take NO for an answer, just = like=20 Columbus, Orville and Wilber, etc.  Scientists also said that the = bumble=20 bee is too heavy to fly, given it's wingspan, etc. Fortunately, no one = has told=20 the bumblebee.  We have been told that EWP's won't work, NACA ducts = won't=20 work for radiators, etc.  Fortunately, we are using them = anyway.  We=20 are fortunate to have an engineer such as yourself on this site, and one = that is=20 willing to listen to evidence from the field as well as numbers and=20 formulas.  A Cozy builder named Al Wick has a Subaru powered Cozy = with his=20 radiator behind a NACA duct, and he can do full power climbs to altitude = with no=20 cooling problems.  I copied his installation. (A google search will = reveal=20 his website).  Thanks again for all of your contributions to this=20 site.  Paul Conner
----- Original Message -----
From:=20 Ed=20 Anderson
Sent: Friday, July 16, 2004 = 6:50 PM
Subject: [FlyRotary] Re: New = Scoop

 I would not argue with your = assessment,=20 Paul.
 
  I mainly put it up so you = folks could see=20 the source that many "experts" use to tell you "Dummies"  why = what you=20 have working - can't possibly work {:>).  I was offering a = hypothesis=20 as to why in some cases the results "in-the-field" might be different = from=20 what NACA found in the wind tunnels.   I had not heard about = the=20 NACA supposedly not being good for carburetors.  My impression = was that=20 so long as there was not back pressure (such as a cooler block will = produce)=20 anything that created a lower than ambient pressure region behind the = NACA=20 duct (such as engine intake or duct into a cabin)  would cause it = to work=20 OK.  I know that the NACA duct that feeds cooling air into my = cabin=20 always has a tremendous rush of air coming through it. Have to keep it = closed=20 off most of the time at altitude or freeze my butt.
 
Ed
 
Ed Anderson
RV-6A N494BW Rotary Powered
Matthews, NC
----- Original Message -----
From:=20 sqpilot@earthlink
To: Rotary motors in = aircraft=20
Sent: Friday, July 16, 2004 = 6:45=20 PM
Subject: [FlyRotary] Re: New=20 Scoop

Hi, Ed.....I am of the opinion that = the NACA=20 report you provided is old and out of date. Note that they also = state that=20 the NACA duct does not provide desireable recovery characteristics = for=20 carburetors on reciprocating engines.  Tell that to the many = LongEZ=20 builders (myself included) that found it to be very efficient in = supplying=20 air to our carburetors in all attitudes, from cruise attitude to = steep=20 climbouts. They came up with a very nice, low drag inlet, but I = don't think=20 they spent as much time studying their creation or finding out it's = true=20 potential.  Just my experience, based upon a very succesful = NACA duct=20 feeding my MS carb on my Lycoming (ugh, sorry about that) powered=20 LongEZ.  Paul Conner
----- Original Message ----- =
From:=20 Ed Anderson
To: Rotary motors in = aircraft=20
Sent: Thursday, July 15, = 2004 6:52=20 PM
Subject: [FlyRotary] Re: = New=20 Scoop

Looking at John's cooling set up, = it=20 appears  that the cooler core exits are in an excellent = position to=20 benefit from any lower  pressure region that may exist = at the=20 rear of the canard fuselage. 
 
Its been my contention that = this=20 is one of the reasons that at least some canard installations = appear=20 to defy  both the conventional "wisdom" and the NACA=20 admonishment that NACA ducts are not well suited for radiator = cooling (or=20 other uses that produce a back pressure).  That is - as = in=20 John's case -  the = successful arrangement appears to=20 minimized the back pressure across the core and = perhaps benefits from=20  a localized area of lower than ambient = pressure.
 
Attached is an extract from a = NACA report=20 which makes it clear, that at least in their opinion at the time, = the NACA=20 ducts were not suited for radiators.  But, as John and = other's have=20 shown, they can work very effectively. So something they are = doing=20 must be different.  The only thing I can come up with is that = the=20 canard arrangement provides the opportunity to benefit from what = must be a=20 lower pressure area behind the fuselage as it moves through the=20 air.  
 
 However, in my own personal = experience=20 in using a Naca duct in the front of my cowling (in one of my five = attempts to solve my oil cooler problem) the results were = consistent with=20 the NACA assessment.  It was not successful for = me.
 
  One of the differences is = my oil=20 cooler was approx 10" from the firewall and did not have exit to a = negative pressure area. In fact, the pressure inside the cowl = was=20 probably slightly positive.   I don't know that would = have made=20 a difference but seeing the success of John and others with it, I = am led=20 to  believe that having the back of your cooler cores in = a lower=20 pressure area will enhance the probability of success in = using a NACA=20 duct. 
 
 
My 0.02 worth.
 
Ed
 
Ed Anderson
RV-6A N494BW Rotary Powered
Matthews, = NC
----- Original Message ----- =
From:=20 John=20 Slade
To: Rotary motors in = aircraft=20
Sent: Thursday, July 15, = 2004 6:48=20 PM
Subject: [FlyRotary] Re: = New=20 Scoop

>I believe that his cowling must extend = down=20 approximately 4-5 inches to achieve that.

Nope. = The cowl is=20 level with the fuselage floor, then curves = upwards.

It's = tight, but it=20 can be done.

John = Slade (Got my=20 EM2 .... manual)

>>  Homepage:  http://www.flyrotary.com/
>&= gt; =20 Archive:   http://lancai= ronline.net/lists/flyrotary/List.html

>>  Homepage: =20 http://www.flyrotary.com/
>>  Archive:  =20 = http://lancaironline.net/lists/flyrotary/List.html
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