X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Sun, 30 May 2010 01:09:28 -0400 Message-ID: X-Original-Return-Path: Received: from mta11.charter.net ([216.33.127.80] verified) by logan.com (CommuniGate Pro SMTP 5.3.7) with ESMTP id 4330201 for lml@lancaironline.net; Sat, 29 May 2010 11:29:27 -0400 Received-SPF: pass receiver=logan.com; client-ip=216.33.127.80; envelope-from=troneill@charter.net Received: from imp10 ([10.20.200.15]) by mta11.charter.net (InterMail vM.7.09.02.04 201-2219-117-106-20090629) with ESMTP id <20100529152850.QVNB14520.mta11.charter.net@imp10> for ; Sat, 29 May 2010 11:28:50 -0400 Received: from [192.168.1.101] ([75.132.241.174]) by imp10 with smtp.charter.net id PTUq1e0073mUFT705TUqv7; Sat, 29 May 2010 11:28:50 -0400 X-Authority-Analysis: v=1.0 c=1 a=b3DeLeuxhZkA:10 a=0qYQvVkOOIcA:10 a=A-lvKEB351AEB2op-e0A:9 a=FPUp0sND_GxYoqZAtqHq3ULmh0UA:4 a=CjuIK1q_8ugA:10 a=eufk39kWk24VPig2bnMA:9 a=yGMfA7vlC8yJU9jZgRsA:7 a=J4vsqeQuPWVdvyXyQhs0K3IUtAcA:4 From: Terrence O'Neill Mime-Version: 1.0 (Apple Message framework v1078) Content-Type: multipart/alternative; boundary=Apple-Mail-1-486986371 Subject: Re: [LML] Re: cowl flap cooling drag reduction X-Original-Date: Sat, 29 May 2010 10:28:49 -0500 In-Reply-To: X-Original-To: "Lancair Mailing List" References: X-Original-Message-Id: <99BBECBF-5EE2-4509-A28A-CB8FFCADC33F@charter.net> X-Mailer: Apple Mail (2.1078) --Apple-Mail-1-486986371 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii Thanks, Gary. =20 Okay, so I think I would keep the L235 cowl inlet area as-is, and be = generous with the flappable outlet area. Actual experience is very reassuring. Terrence L235/320 N2111AL >=20 > I also reduced the inlet area about 20%, adding a diffuser section. = The outlet area was reduced to about half of the original, depending on = what kind of bulges on the bottom are assumed to be "standard." The = cooling is marginal, but adequate - on hot days climb speeds have to be = increased and cruise is done with the flaps open. This is to keep the = CHT's below 400 and oil below 220. Closing the relatively small cowl = flaps increases the speed by 2 to 4 knots.=20 > ES #157, Lycoming engine > =20 --Apple-Mail-1-486986371 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=us-ascii Thanks, Gary.  
Okay, so I think I would = keep the L235 cowl inlet area as-is, and be generous with the flappable = outlet area.
Actual experience is very = reassuring.
Terrence
L235/320 = N2111AL



 I also reduced the = inlet area about 20%, adding a diffuser section.  The outlet area = was reduced to about half of the original, depending on what kind of = bulges on the bottom are assumed to be "standard."  The cooling is = marginal, but adequate - on hot days climb speeds have to be increased = and cruise is done with the flaps open.  This is to keep the CHT's = below 400 and oil below 220.  Closing the relatively small cowl = flaps increases the speed by 2 to 4 knots. 
ES #157, Lycoming = engine