Return-Path: Sender: "Marvin Kaye" To: lml@lancaironline.net Date: Mon, 24 Jan 2005 21:24:04 -0500 Message-ID: X-Original-Return-Path: Received: from [32.97.166.52] (HELO prserv.net) by logan.com (CommuniGate Pro SMTP 4.2.8) with ESMTP id 620318 for lml@lancaironline.net; Mon, 24 Jan 2005 19:56:55 -0500 Received-SPF: none receiver=logan.com; client-ip=32.97.166.52; envelope-from=mhutchins@attglobal.net Received: from marauder (63-227-63-221.dnvr.qwest.net[63.227.63.221]) by prserv.net (asmtp2) with SMTP id <20050125005615252011bkbae> (Authid: atp01); Tue, 25 Jan 2005 00:56:15 +0000 From: "Mike Hutchins" X-Original-To: "Lancair Mailing List" Subject: Alert. NACA 64212 X-Original-Date: Mon, 24 Jan 2005 17:56:15 -0700 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_002C_01C5023E.033A0890" X-Mailer: Microsoft Office Outlook, Build 11.0.6353 Thread-Index: AcUCeKvqPO/nkdblS2mTZrzZdcLtsA== X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-Original-Message-ID: This is a multi-part message in MIME format. ------=_NextPart_000_002C_01C5023E.033A0890 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Buona sera Roberto, Interesting theory about the contribution of lift hysteresis in the stall regime contributing to recovery difficulties. I wonder if NACA/NASA has performed any tests of this behavior using a full scale model? After reviewing the various NACA 6-Series wing sections, it appears that many of the 12% thickness airfoils exhibit similar characteristics. In many cases, this behavior goes away with thicker sections. Alternatively, a slight reprofiling of the wingtip using a 65212 wing section would eliminate this tendency as well, although at the cost of a slightly sharper stall. The sharper stall characteristics can be tamed somewhat by a more generous leading edge radius. Roberto points out yet another reason to consider installing an AOA device in our experimental aircraft. I just wish I could install one in my T210 without an act of congress! Best Regards, Mike ------=_NextPart_000_002C_01C5023E.033A0890 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Buona sera = Roberto,

 

Interesting = theory about the contribution of lift hysteresis in the stall regime = contributing to recovery difficulties. I wonder if NACA/NASA has performed any tests of = this behavior using a full scale model?

 

After = reviewing the various NACA 6-Series wing sections, it appears that many of the 12% = thickness airfoils exhibit similar characteristics. In many cases, this behavior = goes away with thicker sections. Alternatively, a slight reprofiling of the = wingtip using a 65212 wing section would eliminate this tendency as well, = although at the cost of a slightly sharper stall. The sharper stall characteristics = can be tamed somewhat by a more generous leading edge = radius.

 

Roberto = points out yet another reason to consider installing an AOA device in our experimental aircraft. I just wish I could install one in my T210 without an act of = congress!

 

Best = Regards,

Mike

 

------=_NextPart_000_002C_01C5023E.033A0890--