X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from fed1rmmtao106.cox.net ([68.230.241.40] verified) by logan.com (CommuniGate Pro SMTP 5.2.0) with ESMTP id 2774879 for flyrotary@lancaironline.net; Mon, 03 Mar 2008 11:09:45 -0500 Received-SPF: none receiver=logan.com; client-ip=68.230.241.40; envelope-from=alventures@cox.net Received: from fed1rmimpo03.cox.net ([70.169.32.75]) by fed1rmmtao106.cox.net (InterMail vM.7.08.02.01 201-2186-121-102-20070209) with ESMTP id <20080303160905.WDIR3976.fed1rmmtao106.cox.net@fed1rmimpo03.cox.net> for ; Mon, 3 Mar 2008 11:09:05 -0500 Received: from BigAl ([72.192.137.74]) by fed1rmimpo03.cox.net with bizsmtp id wg8b1Y00U1cVYgg0000000; Mon, 03 Mar 2008 11:08:36 -0500 From: "Al Gietzen" To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Re: Cooling the 20B Date: Mon, 3 Mar 2008 08:11:04 -0800 Message-ID: <000001c87d49$2ec49960$6401a8c0@BigAl> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0001_01C87D06.20A15960" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.6626 Importance: Normal In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3198 This is a multi-part message in MIME format. ------=_NextPart_000_0001_01C87D06.20A15960 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Al, =20 I have the Spal 11" medium thickness fan. 970 CFM. =20 =20 If I understand correctly, your Velocity has no way to move air through = the radiators when sitting on the ground except your fan.?? True?? =20 Somewhat true. The prop does create negative pressure behind the cowl = which draws air through the radiator that is in the cowl - I was actually surprised by how much - WAG, maybe 500 cfm at taxi rpm of about 2000 - = 2200. =20 How well does it cool when you are on the ground? Are you hot by the = time you get to the runway ready for takeoff? On a 70F day, I can startup, listen to ATIS, talk to ground, taxi the = 2700 ft to run-up area, do the runup checks; and the temps will be about 170 = -175 - no fan. If I get immediate clearance I proceed to takeoff. If I have = to wait, I'll turn on the aux fan, and that will keep the temps stable at = 1000 -1200 rpm idle, probably indefinitely. Oil temp will go 10 - 20F = higher. My rule of thumb is that if the temps get to 170-175 while I'm on the = ground, I turn on the fan; so on a hot day that may happen by the time I start the run-up. =20 Since installing the fan, I have never shut the engine down while = waiting for takeoff clearance. I suspect that on a 90+ day, with much of an anticipated wait; I'd shutdown - just off the fuel pump, and sit there. = When clearance comes, pump on, touch the starter and it goes. I know - it = makes you nervous; but the thing starts easily. =20 Al =20 =20 Bill B =20 _____ =20 From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Al Gietzen Sent: Sunday, March 02, 2008 2:54 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Cooling the 20B Al, do you recall the CFMs of your fan? And/or dimensions? =20 Bill B=20 Bill; =20 This link is the one I am using ('pull' version): =20 http://www.jaycorptech.com/showproduct.aspx?productid=3D11 &categoryid=3D2 =20 This link shows you all the options available: http://www.jaycorptech.com/showcategory.aspx?categoryid=3D2 =20 Al =20 =20 ------=_NextPart_000_0001_01C87D06.20A15960 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Al,

 

I have the Spal 11” medium thickness = fan.  970 CFM. 

 

If I understand correctly, your Velocity has = no way to move air through the radiators when sitting on the ground except your fan…?? True??

 

Somewhat true.  The prop = does create negative pressure behind the cowl which draws air through the = radiator that is in the cowl – I was actually surprised by how much – = WAG, maybe 500 cfm at taxi rpm of about 2000 - 2200.

 

How well does it cool when you are on the ground? Are you hot by the time you get to the runway ready for = takeoff?

On a 70F day, I can startup, = listen to ATIS, talk to ground, taxi the 2700 ft to run-up area, do the runup = checks; and the temps will be about 170 -175 – no fan.  If I get = immediate clearance I proceed to takeoff.  If I have to wait, I’ll turn on the = aux fan, and that will keep the temps stable at 1000 -1200 rpm idle, probably = indefinitely.  Oil temp will go 10 – 20F higher. My rule of thumb is that if the = temps get to 170-175 while I’m on the ground, I turn on the fan; so on a = hot day that may happen by the time I start the run-up.

 

Since installing the fan, I have = never shut the engine down while waiting for takeoff clearance.  I = suspect that on a 90+ day, with much of an anticipated wait; I’d shutdown = – just off the fuel pump, and sit there. When clearance comes, pump on, touch = the starter and it goes. I know – it makes you nervous; but the thing = starts easily.

 

Al

 

 

Bill B

 

From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Al Gietzen
Sent: Sunday, March 02, 2008 2:54 = PM
To: Rotary motors in = aircraft
Subject: [FlyRotary] Re: = Cooling the 20B

Al, do you recall the CFMs of your fan?  = And/or dimensions?

 

Bill B 

Bill;

 

This link is the one I am using (‘pull’ = version):

 

http://www.jaycorptech.com/showproduct.aspx?productid=3D11&= amp;categoryid=3D2

 

This link shows you all the options available:

http= ://www.jaycorptech.com/showcategory.aspx?categoryid=3D2=

 

Al

 

 

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