X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Sat, 02 Jul 2011 23:34:10 -0400 Message-ID: X-Original-Return-Path: Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122] verified) by logan.com (CommuniGate Pro SMTP 5.4.0) with ESMTP id 5040645 for lml@lancaironline.net; Sat, 02 Jul 2011 13:59:51 -0400 Received-SPF: none receiver=logan.com; client-ip=71.74.56.122; envelope-from=Wolfgang@MiCom.net X-Original-Return-Path: X-Authority-Analysis: v=1.1 cv=yMxAJ7W7nAoPh8ZdbvCArpG6pAdHwgpzIvOq8QbMesM= c=1 sm=0 a=aH2ddMUXAssA:10 a=ttCsPuSJ-FAA:10 a=MHZY6FYWMEQOp7S43i2QIw==:17 a=Ia-xEzejAAAA:8 a=3oc9M9_CAAAA:8 a=tYZPWW6eAAAA:8 a=CjxXgO3LAAAA:8 a=V5a7qabo_EBBxxMxxWgA:9 a=G8D6A_obBA6-Q5_2NfoA:7 a=QEXdDO2ut3YA:10 a=-ZBvsNeBbbMA:10 a=EzXvWhQp4_cA:10 a=U8Ie8EnqySEA:10 a=b1KJu6T2Jp8A:10 a=rC2wZJ5BpNYA:10 a=I3NkH7RJYdItyZn5ztkA:9 a=ROK9Nzu2vN6X0j1tOe0A:7 a=tXsnliwV7b4A:10 a=MHZY6FYWMEQOp7S43i2QIw==:117 X-Cloudmark-Score: 0 X-Originating-IP: 74.218.201.50 Received: from [74.218.201.50] ([74.218.201.50:2371] helo=lobo) by hrndva-oedge01.mail.rr.com (envelope-from ) (ecelerity 2.2.3.46 r()) with ESMTP id F4/28-07441-37C5F0E4; Sat, 02 Jul 2011 17:59:15 +0000 X-Original-Message-ID: <001b01cc38e1$bec48910$6401a8c0@lobo> From: "Wolfgang" X-Original-To: Subject: Re: [LML] Re: Ventral Strakes, do they reduce performance? X-Original-Date: Sat, 2 Jul 2011 13:59:10 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0018_01CC38C0.377BFA90" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 This is a multi-part message in MIME format. ------=_NextPart_000_0018_01CC38C0.377BFA90 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable A fast servo driven trim tab on the rudder driven by a solid state rate = gyro from the model helicopter industry may do the trick. Wolfgang ----- Original Message -----=20 From: J H Webb=20 To: lml@lancaironline.net=20 Sent: Saturday, July 02, 2011 1:23 AM Subject: Re: [LML] Re: Ventral Strakes, do they reduce performance? I second Jeff's comment that a yaw damper is not really necessary on = the LIV P. Although it would be an improvement for a LIV PT. A true high = frequency yaw damper that did not move the rudder petals would improve = the ride in turbulence but none are available for GA.=20 Jack Webb L360, LIV=20 AeroSpace Engineer BSAE=20 FAA Designated Check airman for C421, C404 & C310 ATP, CFI Airplanes & Instruments, Multi, & Sea Numerous Jet Type Ratings Experienced Experimental Test Pilot both multi and single engine = aircraft Former Chief Engineering Test Pilot for a Major Manufacturer Ohio -------------------------------------------------------------------------= ----- From: "vtailjeff@aol.com" To: lml@lancaironline.net Sent: Friday, July 1, 2011 7:45 AM Subject: [LML] Re: Ventral Strakes, do they reduce performance? You do not need a yaw damper in the IVP. Jeff Sent from my iPad On Jun 30, 2011, at 6:10 PM, Ronald STEVENS wrote: Hi Jack Thanks for the explanations, I have the Tru-Trak sorcerer installed = in my plane and was planning the Yaw damper as it is said that the 4p = changes yaw with every speed change, so I am assuming the yaw damper = together with the auto trim would correct this issue, right? =3D=3D Ronald From: J H Webb Reply-To: Lancair Mailing List Date: Thu, 30 Jun 2011 15:06:20 -0400 To: Subject: [LML] Re: Ventral Strakes, do they reduce performance? Ron, Sorry it has taken so long but I have been busy. You have asked = several questions, and on the question of Ventral fins, I have had = installed Ventral fins on several LIV's. The need is much greater for = the LIV-PT but there is an improvement in both piston and turbine = models. The little dual fins are not as effective as one larger single = fin. Plus the drag seems to be lower. I have designed a single fin shape = that works well, no noticeable impact on cruise speed. I did notice a slight speed reduction with the twin Ventral fin taht = are used on several LIV-PT's. Clark Still's aircraft is a good example of a PT with the single = fin Ventral fin, on that airplane we made a very significant improvement = in directional stability. On the question about yaw dampers, the yaw damper is very = helpful when it is a high frequency unit with no feedback in the = rudders. Unfortunately hte yaw dampers available currently are on = limited value plus the current units that connect directly to the rudder = increase the rudder friction band significantly making the airplane more = difficult to master yaw control. The ideal installation would a unit = operating a separate control surface such as the trailing edge of the = ventral fin. Jack Webb L360, LIV=20 AeroSpace Engineer BSAE=20 FAA Designated Check airman for C421, C404 & C310 ATP, CFI Airplanes & Instruments, Multi, & Sea Numerous Jet Type Ratings Experienced Experimental Test Pilot both multi and single engine = aircraft Former Chief Engineering Test Pilot for a Major Manufacturer Corporate Chief Pilot for Construction company Ohio Flying is the perfect vocation for a man who wants to feel like a = boy, but not for one who still is. -------------------------------------------------------------------------= --- From: RONALD STEVENS To: lml@lancaironline.net Sent: Monday, June 27, 2011 7:34 AM Subject: [LML] Ventral Strakes, do they reduce performance? Hello guys Me again, I just had my first lesson with the Lancair 4p (with JC) = and when I took off the plane was wiggling its tail like a happy dog LOL = Nothing scary, but this I can imagine could be annoying for passengers. Now I was looking on the internet and found that Ventral Strakes = were used to fight against those 'yaw' effects. It suppose to help with turbulence, go-arrounds, full power take = offs as well. My very near future plane (we are almost closing ;) is a newer one, = so the tail section was already updated to the latest.=20 But looking at my passengers (I fly with my Son and Girlfriend a = lot) this could be disturbing for them and I was already thinking of = installing the Yaw damper (I have the tru-trak sorcerer) and perhaps = also installing those Ventral strakes. Does anybody have experience (before and after) with those? And = would you recommend those?=20 Thanks =E2=80=94 Ronald Stevens (Cirrus 1100 hours, Velocity 250 = hours, Lancair 4p student now with 1 hour LOL) ------=_NextPart_000_0018_01CC38C0.377BFA90 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable =EF=BB=BF
A fast servo driven trim tab on the = rudder driven=20 by a solid state rate gyro from the model helicopter industry may do the = trick.
 
Wolfgang
 
----- Original Message -----
From:=20 J H = Webb=20
Sent: Saturday, July 02, 2011 = 1:23=20 AM
Subject: Re: [LML] Re: Ventral = Strakes,=20 do they reduce performance?

I second Jeff's comment that a yaw damper is not really = necessary=20 on the LIV P. Although it would be an improvement for a LIV PT. A true = high=20 frequency yaw damper that did not move the rudder petals would improve = the=20 ride in turbulence but none are available for GA. 

Jack=20 Webb
L360, LIV
AeroSpace=20 Engineer BSAE
FAA Designated Check airman for C421, C404 &=20 C310
ATP, CFI Airplanes & Instruments, Multi, & = Sea
Numerous Jet=20 Type Ratings
Experienced Experimental Test Pilot both multi and = single=20 engine aircraft
Former Chief Engineering Test Pilot for a Major=20 Manufacturer
Ohio

From: = "vtailjeff@aol.com"=20 <vtailjeff@aol.com>
To:=20 lml@lancaironline.net
Sent:=20 Friday, July 1, 2011 7:45 AM
Subject: [LML] Re: Ventral = Strakes, do=20 they reduce performance?

You do not need a yaw damper in the IVP.

Jeff

Sent from my iPad

On Jun 30, 2011, at 6:10 PM, Ronald STEVENS <Ronald@sdc.com> = wrote:

Hi Jack

Thanks for the explanations, I have the Tru-Trak = sorcerer=20 installed in my plane and was planning the Yaw damper as it is said = that the=20 4p changes yaw with every speed change, so I am assuming the yaw = damper=20 together with the auto trim would correct this issue, = right?

=3D=3D Ronald

From: J H Webb <airmale4@yahoo.com>
Reply-To: Lancair Mailing List = <lml@lancaironline.net>Date: Thu, 30 Jun 2011 15:06:20=20 -0400
To: <lml@lancaironline.net>Subject: [LML] Re: Ventral = Strakes, do they=20 reduce performance?

Ron,

    Sorry it has taken so long but I have = been=20 busy. You have asked several questions, and on the question of = Ventral fins,=20 I have had installed Ventral fins on several LIV's. The need is much = greater=20 for the LIV-PT but there is an improvement in both piston and = turbine=20 models. The little dual fins are not as effective as one larger = single fin.=20 Plus the drag seems to be lower. I have designed a single fin shape = that=20 works well, no noticeable impact on cruise speed.
I did notice a slight speed reduction with the twin = Ventral fin=20 taht are used on several LIV-PT's.
  Clark Still's aircraft is a good example of a PT with = the single=20 fin Ventral fin, on that airplane we made a very significant = improvement in=20 directional stability.
     On the question about yaw = dampers, the=20 yaw damper is very helpful when it is a high frequency unit with no = feedback=20 in the rudders. Unfortunately hte yaw dampers available currently = are on=20 limited value plus the current units that connect directly to the = rudder=20 increase the rudder friction band significantly making the airplane = more=20 difficult to master yaw control. The ideal installation would a unit = operating a separate control surface such as the trailing edge of = the=20 ventral fin.

Jack=20 Webb
L360, LIV
AeroSpace=20 Engineer BSAE
FAA Designated Check airman for C421, C404 &=20 C310
ATP, CFI Airplanes & Instruments, Multi, & = Sea
Numerous=20 Jet Type Ratings
Experienced Experimental Test Pilot both multi = and=20 single engine aircraft
Former Chief Engineering Test Pilot for a = Major=20 Manufacturer
Corporate=20 Chief Pilot for Construction company
Ohio

Flying=20 is the perfect vocation for a man who wants to feel like a boy, but = not for=20 one who still is.

From: RONALD STEVENS = <ronald@sdc.com>
To: lml@lancaironline.net
= Sent: Monday, June 27, 2011 = 7:34=20 AM
Subject: [LML] = Ventral=20 Strakes, do they reduce performance?

Hello guys

Me again, I just had my first lesson with the Lancair 4p (with = JC) and=20 when I took off the plane was wiggling its tail like a happy dog LOL = Nothing=20 scary, but this I can imagine could be annoying for = passengers.

Now I was looking on the internet and found = that Ventral=20 Strakes  were used to fight against those 'yaw' = effects.
It suppose to help with turbulence, go-arrounds, full power = take offs=20 as well.

My very near future plane (we are almost closing ;) is a newer = one, so=20 the tail section was already updated to the latest. 

But looking at my passengers (I fly with my Son and Girlfriend = a lot)=20 this could be disturbing for them and I was already thinking of = installing=20 the Yaw damper (I have the tru-trak sorcerer) and perhaps also = installing=20 those Ventral strakes.

Does anybody have experience (before and after) with those? And = would=20 you recommend those? 

Thanks =E2=80=94 Ronald Stevens (Cirrus 1100 hours, Velocity = 250 hours, Lancair=20 4p student now with 1 hour=20 = LOL)




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