X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 29 Jun 2011 07:34:46 -0400 Message-ID: X-Original-Return-Path: Received: from [198.64.152.110] (HELO sdc.com) by logan.com (CommuniGate Pro SMTP 5.4.0) with ESMTP id 5036149 for lml@lancaironline.net; Tue, 28 Jun 2011 18:13:20 -0400 Received-SPF: pass receiver=logan.com; client-ip=198.64.152.110; envelope-from=Ronald@sdc.com Received: from [192.168.0.14] [68.202.59.0] by sdc.com with ESMTP (SMTPD-11.5) id fad60002206961b2; Tue, 28 Jun 2011 18:03:12 -0400 User-Agent: Microsoft-MacOutlook/14.0.0.100825 X-Original-Date: Tue, 28 Jun 2011 18:12:41 -0400 Subject: Re: [LML] Re: Airplane needs to be "fixed," Stall Speeds, Wing Cuffs, Vortex Generators for L... From: Ronald STEVENS X-Original-To: Lancair Mailing List X-Original-Message-ID: Thread-Topic: [LML] Re: Airplane needs to be "fixed," Stall Speeds, Wing Cuffs, Vortex Generators for L... In-Reply-To: Mime-version: 1.0 Content-type: multipart/alternative; boundary="B_3392129564_36336858" > This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. --B_3392129564_36336858 Content-type: text/plain; charset="ISO-8859-1" Content-transfer-encoding: quoted-printable Wow, Terrence, this was a great explanation, I truly want to express my gratitude here. I might have stepped on some toes, perhaps asked too much, are too much of a 'pain in the =8A' with my questions, but I think that each pilot should get informed into what he is getting into when he is transitioning into a new plane. Each plane has its own character, and especially experimental ones, because there is the 'owner/builder' factor we also have to encounter for. I was test flying my new plane in Redmond last week and I am thrilled to sa= y that it was built very well, and the slow speed indications on this particular plane was very good. At 100kts it was very responsive to the ailerons, and the AOA was still at a good margin. Later more about this=8A.. The responses on this board has been very educative, and I am sure many 'lurkers' did learn some extra things in here as well. So also to all other= s as well, thanks again from a new Lancair 4p owner/pilot/student :) Ronald Stevens (Cirrus sr22 1100hours, Velocity TXL5 260hours, Lancair Evolution 3 hours, lancair 4p 1 hour ;)~ =20 From: Terrence O'Neill Reply-To: Lancair Mailing List Date: Tue, 28 Jun 2011 13:11:48 -0400 To: Subject: [LML] Re: Airplane needs to be "fixed," Stall Speeds, Wing Cuffs, Vortex Generators for L... If I may, comparatively briefly: We all know the word 'stall' refers the wing's airflow breaking away at a certain angle. You, the pilot, controls the angle at which the airflow approaches the wing. Hands off the pitch control that angle stays where you trimmed it, regardless of attitude. You probably don't really believe that. but it's true -- unless -- you are too far aft CG, or the total airplane has a pitching moment that increases 'nose-up' as the AOA increases. Many (military) aircraft with artificial stabilization are designed to use all lifting surfaces to get the best L/D, for more performance -- at the cost of stability. GenAv planes don't. Some Experimentals are marginally stable or even unstable when at high AOAs. Add to that, all the fatal GenAv accidents are caused by unintentional stalls, a quarter to a third of all fatals. Because the pilot pulled his wing past its stall AOA .. unintentionally. Unintentionally, because he can not SEE the air-to-wing angle. Because he does not habitually reference how he is 'planing' his wing. He uses airspeed, a very vague, inaccurate reference to the wing-wing angle. For GenAv planes, the FAA persistently, ignorantly, does not require all airplanes to have an AOA indicating vane right in the pilot's field of vision, and require him to demonstrate using it, to get his license. The great majority of pilots are not aerodynamics guys who have designed an airplane, built their own design, and then got in it and risked their life on their own design knowledge. Most know about AOA, but don't understand it -- or use it. I was ignorant too, in spite of my Navy wings and five more year of GenAv flying. Until 1960 when I bought Waco's last prototype Experimental and restored and flew it, and then conducted a FAA Type Certification program for my own similar design, a 6-seater ... then I realized I needed to reall= y understand what was going on at high AOAs, and started making my own AOA vanes, so I could see the angles, down to one degree, and watch them as I maneuvered the plane, stalled and unstalled the wing, watched the vane move as I moved the wheel in and out, like there was a string attached to the AO= A vane. It makes me so sad, every time I see a stall-related crash ... friends and compatriots, year after year, hundreds of great aircraft and wonderful people, die unnecessarily. Why? =20 The GenAv survivors should blame the FAA and manufacturers' marketing departments. =20 We Experimenters have only ourselves to blame. We don't believe in AOAs. W= e don't want to take the time or spend the money. We don't want to make our beautiful planes ugly. We don't want to degrade performance one mph. We don't want to learn new tricks. We're great pilots, and we'll never make that mistake. But a few of us do. Please excuse my continued harping on this. It's just 'tough love'. Terrence L235/320 N211AL --B_3392129564_36336858 Content-type: text/html; charset="ISO-8859-1" Content-transfer-encoding: quoted-printable
Wow, Terrence, this was a gr= eat explanation, I truly want to express my gratitude here. I might have ste= pped on some toes, perhaps asked too much, are too much of a 'pain in the &#= 8230;' with my questions, but I think that each pilot should get informed in= to what he is getting into when he is transitioning into a new plane.
<= div>
Each plane has its own character, and especially experime= ntal ones, because there is the 'owner/builder' factor we also have to encou= nter for.

I was test flying my new plane in Redmond= last week and I am thrilled to say that it was built very well, and the slo= w speed indications on this particular plane was very good. At 100kts it was= very responsive to the ailerons, and the AOA was still at a good margin. La= ter more about this…..

The responses on this = board has been very educative, and I am sure many 'lurkers' did learn some e= xtra things in here as well. So also to all others as well, thanks again fro= m a new Lancair 4p owner/pilot/student :)

Ronald St= evens (Cirrus sr22 1100hours, Velocity TXL5 260hours, Lancair Evolution 3 ho= urs, lancair 4p 1 hour ;)~

 

= From: Terrence O'Neill <troneill@charter.net>
Reply-To: Lancair Mailing List <lml@lancaironline.net>
Date: Tue, 28 Jun 2011 13:11:48 -0400
To: <lml@lanc= aironline.net>
Subject: [LM= L] Re: Airplane needs to be "fixed," Stall Speeds, Wing Cuffs, Vortex Genera= tors for L...

If I ma= y, comparatively briefly:
We all know the word 'stall' refers the wing's= airflow breaking away at a certain angle.
You,  the pilot, c= ontrols the angle at which the airflow approaches the wing.  Hands off = the pitch control that angle stays where you trimmed it, regardless of attit= ude. You probably don't really believe that. but it's true -- unless -- you = are too far aft CG, or the total airplane has a pitching moment that increas= es 'nose-up' as the AOA increases.

Many (military) = aircraft with artificial stabilization are designed to use all lifting surfa= ces to get the best L/D, for more performance -- at the cost of stability.
GenAv planes don't. Some Experimentals are marginally stable or eve= n unstable when at high AOAs.  Add to that, all the fatal GenAv acciden= ts are caused by unintentional stalls, a quarter to a third of all fa= tals.
Because the pilot pulled his wing past its stall AOA .. unin= tentionally.
Unintentionally, because he can not SEE the air-to-wi= ng angle.  Because he does not habitually reference how he is 'planing'= his wing.  He uses airspeed, a very vague, inaccurate reference to the= wing-wing angle.
For GenAv planes, the FAA persistently, ignorant= ly, does not require all airplanes to have an AOA indicating vane right in t= he pilot's field of vision, and require him to demonstrate using it, to get = his license.

The great majority of pilots are not a= erodynamics guys who have designed an airplane, built their own design, and = then got in it and risked their life on their own design knowledge.   M= ost know about AOA, but don't understand it -- or use it.
I was ig= norant too, in spite of my Navy wings and five more year of GenAv flying. &n= bsp;Until 1960 when I bought Waco's last prototype Experimental and restored= and flew it, and then conducted a FAA Type Certification program for my own= similar design, a 6-seater ... then I realized I needed to really understan= d what was going on at high AOAs, and started making my own AOA vanes, so I = could see the angles, down to one degree, and watch them as I maneuvered the= plane, stalled and unstalled the wing, watched the vane move as I moved the= wheel in and out, like there was a string attached to the AOA vane.

It makes me so sad, every time I see a stall-related crash= ... friends and compatriots, year after year, hundreds of great aircraft an= d wonderful people, die unnecessarily.  
Why?  
The GenAv survivors should blame the FAA and manufacturers' marketing depa= rtments.  
We Experimenters have only ourselves to blame. We = don't believe in AOAs.  We don't want to take the time or spend the mon= ey.  We don't want to make our beautiful planes ugly.  We don't wa= nt to degrade performance one mph.  We don't want to learn new tricks. =  We're great pilots, and we'll never make that mistake. But a few of us= do.
Please excuse my continued harping on this.  It's just '= tough love'.

Terrence
L235/320 N211AL

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