X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Tue, 22 Nov 2011 07:53:10 -0500 Message-ID: X-Original-Return-Path: Received: from carbinge.com ([69.5.27.218] verified) by logan.com (CommuniGate Pro SMTP 5.4.2) with SMTP id 5208614 for lml@lancaironline.net; Mon, 21 Nov 2011 10:45:11 -0500 Received-SPF: none receiver=logan.com; client-ip=69.5.27.218; envelope-from=jbarrett@carbinge.com Received: (qmail 31800 invoked from network); 21 Nov 2011 15:44:36 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; h=X-Originating-IP:Reply-To:From:To:References:In-Reply-To:Subject:Date:Message-ID:MIME-Version:Content-Type:X-Mailer:Thread-Index:Content-Language; s=default; d=carbinge.com; b=EZtry8+/DBGblzUAdbR9XjTXjfEDvUyzyxsB40wnPF+6vfjfDpdoyoI0lZLA7nSmqNZRzr826NdMARhIzdyDOgWevuyl5WexbvE7/TOlfSaeJx7BVrNeQuzQhSpqM6i1krvk60fTBTddOaeUkXWTNPCiB87myLH7iECU7AoeYP0=; X-Originating-IP: [24.143.114.8] Reply-To: From: "John Barrett" X-Original-To: "'Lancair Mailing List'" References: In-Reply-To: Subject: RE: [LML] Re: Legacy vibrations resolved X-Original-Date: Mon, 21 Nov 2011 07:44:34 -0800 X-Original-Message-ID: <00bc01cca864$783c3770$68b4a650$@com> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_00BD_01CCA821.6A18F770" X-Mailer: Microsoft Office Outlook 12.0 Thread-Index: AcyoUYmG8/DEegXRSpy/2Kdp86DYiQAEtKnA Content-Language: en-us This is a multi-part message in MIME format. ------=_NextPart_000_00BD_01CCA821.6A18F770 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable CARBINGE =20 FWIW it=E2=80=99s worth a lot. =20 www.carbinge.com =20 =20 From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of = randy snarr Sent: Monday, November 21, 2011 5:29 AM To: lml@lancaironline.net Subject: [LML] Re: Legacy vibrations resolved =20 Steve, As a side note, I had a legacy driver stop by my hangar a few years ago. = When he shut down, there was a definite metal on metal rattle in the = tail as the blades came to a stop. I started inspecting the back of his = plane before he got out. He had the same play in the hinges. Especially = the outer hinge pilot side. With the airplane idling, the hinges rattled pretty bad but with the = engine running you could not hear it but it was defintely there at shut = down. The tell tale gray trails were there as well.=20 =20 FWIW.. Randy. =20 "Flight by machines heavier than air is unpractical and insignificant, = if not utterly impossible" -Simon Newcomb, 1902 _____ =20 From: Steve Colwell To: lml@lancaironline.net=20 Sent: Sunday, November 20, 2011 7:48 AM Subject: [LML] Legacy vibrations resolved Our Legacy has had a pitch vibration in the stick that comes and goes. = It seems to be related to about 50% fuel load or less and reduced but = stable power. The plane has about 275 hours and this has been going on = since the first 40 hours. When it is vibrating in level flight = (approximately 2 cycles per second and the stick is visibly moving in a = pronounced shake) it will continue to vibrate when pitched up at about = 1.5 G. After the pitch up, when pitched down to less than 1 G, the = vibration will quit. After working thru many of the same contact = points firewall forward and the gear doors Paul Miller had, I still had = the vibration. All the while, I'm thinking, this is a great way to = initiate flutter. I might add, I very carefully rebalanced the control = surfaces after painting.=20 =20 I mentioned the problem to Chris Zavatson at the Lancair Breakfast = Fly-In at Willows, CA.. Chris asked if I had checked the control and = trim hinges for play. That was easy, I check them every pre-flight. = Only not the way Chris checks them. He pushes and pulls looking at the = hinge. See video http://www.n91cz.com/HingePlay/hinges.htm=20 =20 I replaced the Pitch Trim Hinge Pin with Stainless Steel (3/32=E2=80=9D = - .09375) welding wire. Now, no play can be seen in the push pull test. = We have put 20+ hours on with the new SS hinge pin and no more stick = shake. I included Paul=E2=80=99s post of problem areas (see below) = since I had some of them too. =20 =20 Steve Colwell Legacy RG 310 hours =20 Sent: Monday, April 12, 2010 6:47 AM To: lml@lancaironline.net Subject: [LML] Legacy vibrations resolved =20 I had written about vibrations in the 300 hour Legacy engine=20 compartment. Many wrote about their fixes. I am happy to report that=20 the following worked for me: =20 1) Changed engine isolators last year (no difference) 2) enlarged cutout on nose gear door stiffener. After repeatedly seeing = new witness marks I did a retraction test and saw the interference is = much larger than I expected. I trimmed another 1/8 inch from the = cutout. This cutout prevents interference from the bolt attaching the = linkage to the nose gear on both sides. The co-pilot side needed a = larger cutout. White primer was used to show the marks after each = flight. I think this was transmitting a lot of cowl vibration. 3) I sprayed white primer on the areas contacting the baffling. I=20 found three hard hit areas and this is using the factory white powder = coated baffling. Two areas at the front of the #5 cylinder needed = bending away from the cowl. Another area just above the oil cooler on = the top side of the cowl was hitting. The #5 EGT probe was hitting. =20 The #5 forward rocker cover was hitting on the bottom and was peened = about a 1/4 to match the form of the cowl. I removed the rocker cover = to check for clearance with the rocker arm. 4) Baffling repairs were made to areas that were not tight against the=20 cowl. This significantly reduced the CHTs. I used the cooling and=20 drag reduction data on lml from owners to help make small but helpful = changes in the baffling. 5) The prop governor cable was a hard hit on the metal baffling and was = trimmed. 6) The nose gear doors had a slight overlap which was trimmed so they = close tight with no gaps. 7) Both main gear inner and outer doors were adjusted to be flush and = tight when retracted. This took a significant amount of time involving = small hinge adjustments and testing of each individual attachment link = on the outer doors to get the right length before attaching both links = for the final test. I say this because the two links are slightly = different in length and geometry. I found one was a little longer than = required and actually twisted the door slightly open when both links = were attached. This was not evident until I retracted the gear using = only single links. 8) the large circular baffle behind the prop is cracked in two places = and remains that way until a fix can be made. This appears to be from a = tight fit and needs to be measured for a new smaller piece. This is a = large crack that could easily be flopping around in flight and somehow = interfering with the cooling process. 9) removed the quick drain for oil and replaced with the factory plug. =20 I have lots of clearance and may put the quick drain back in. =20 The net result is now I have a smooth engine compartment. My symptoms=20 included a difficult propeller balancing as we could never exactly home = in on a solution. The vibration was small at 2700 rpm and takeoff but = increased significantly with rpm reduction. I attribute that to the = higher torque twisting the engine closer to the left side of the = baffling. The vibration was evident in the cockpit, cowling and when = looking at the wings. The next project will be to replace the silicone = baffle with new material and replace the circular baffle plate behind = the prop and replace the left side metal baffle to better fit the cowl = line near the #5 cylinder. Many thanks to all the suggestions that made = this easier to do. =20 Paul Miller N357V Legacy RG =20 ------=_NextPart_000_00BD_01CCA821.6A18F770 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable

CARBINGE

 

FWIW=C2=A0 it=E2=80=99s worth a lot.

 

www.carbinge.com

 

 

From:= = Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of = randy snarr
Sent: Monday, November 21, 2011 5:29 = AM
To: lml@lancaironline.net
Subject: [LML] Re: = Legacy vibrations resolved

 

Steve,

As a side note, I had a legacy driver stop by my = hangar a few years ago. When he shut down, there was a definite metal on = metal rattle in the tail as the blades came to a stop. I started = inspecting the back of his plane before he got out. He had the same play = in the hinges. Especially the outer hinge pilot side.
With the = airplane idling, the hinges rattled pretty bad but with the engine = running you could not hear it but it was defintely there at shut down. = The tell tale gray trails were there as well. =

 

FWIW..
Randy.

 

"Flight by machines heavier than air is = unpractical and insignificant, if not utterly = impossible"
-Simon = Newcomb, 1902

<= hr size=3D1 width=3D"100%" align=3Dcenter>

F= rom: = Steve Colwell <mcmess1919@yahoo.com>
To: = lml@lancaironline.net
Sent: Sunday, November 20, 2011 7:48 = AM
Subject: [LML] Legacy vibrations resolved

Our Legacy has = had a pitch vibration in the stick that comes and goes.  It seems = to be related to about 50% fuel load or less and reduced but stable = power.  The plane has about 275 hours and this has been going on = since the first 40 hours.  When it is vibrating in level flight = (approximately 2 cycles per second and the stick is visibly moving in a = pronounced shake) it will continue to vibrate when pitched up at about = 1.5 G.  After the pitch up, when pitched down to less than 1 G, the = vibration will quit.   After working thru many of the same = contact points firewall forward and the gear doors Paul Miller had, I = still had the vibration. All the while, I'm thinking, this is a great = way to initiate flutter.  I might add, I very carefully rebalanced = the control surfaces after painting.

 

I mentioned the problem to Chris Zavatson at the = Lancair Breakfast Fly-In at Willows, CA..  Chris asked if I had = checked the control and trim hinges for play.  That was easy, I = check them every pre-flight.  Only not the way Chris checks them. = He pushes and pulls looking at the hinge.  See video  = http://www.n91cz.com/HingePlay/hinges.htm =

 

I replaced the Pitch Trim Hinge Pin with Stainless = Steel (3/32=E2=80=9D - .09375) welding wire.  Now, no play can be = seen in the push pull test.  We have put 20+ hours on with the new = SS hinge pin and no more stick shake.  I included Paul=E2=80=99s = post of problem areas (see below) since I had some of them too. =  

 

Steve Colwell  Legacy RG 310 = hours

 


Sent: Monday, April 12, 2010 6:47 AM
To: = lml@lancaironline.net
Subject: [LML] Legacy vibrations = resolved

 

I had written about vibrations in the 300 hour = Legacy engine

compartment.  Many wrote about their = fixes.   I am happy to report that =

the following = worked for me:

 

1) Changed engine isolators last year (no = difference)

2) enlarged = cutout on nose gear door stiffener.  After repeatedly seeing new = witness marks I did a retraction test and saw the interference is much = larger than I expected.  I trimmed another 1/8 inch from the = cutout.  This cutout prevents interference from the bolt attaching = the linkage to the nose gear on both sides.  The co-pilot side = needed a larger cutout.  White primer was used to show the marks = after each flight.  I think this was transmitting a lot of cowl = vibration.

3) I sprayed = white primer on the areas contacting the baffling.   I =

found three hard = hit areas and this is using the factory white powder coated = baffling.  Two areas at the front of the #5 cylinder needed bending = away from the cowl.  Another area just above the oil cooler on the = top side of the cowl was hitting.  The #5 EGT probe was = hitting. 

The #5 forward = rocker cover was hitting on the bottom and was peened about a 1/4 to = match the form of the cowl.  I removed the rocker cover to check = for clearance with the rocker arm.

4) Baffling repairs were made to areas that were = not tight against the

cowl.   This significantly reduced the = CHTs.  I used the cooling and

drag reduction data on lml from owners to help = make small but helpful changes in the = baffling.

5) The prop = governor cable was a hard hit on the metal baffling and was = trimmed.

6) The nose gear = doors had a slight overlap which was trimmed so they close tight with no = gaps.

7) Both main gear = inner and outer doors were adjusted to be flush and tight when = retracted.  This took a significant amount of time involving small = hinge adjustments and testing of each individual attachment link on the = outer doors to get the right length before attaching both links for the = final test.  I say this because the two links are slightly = different in length and geometry.  I found one was a little longer = than required and actually twisted the door slightly open when both = links were attached.  This was not evident until I retracted the = gear using only single links.

8) the large circular baffle behind the prop is = cracked in two places and remains that way until a fix can be = made.  This appears to be from a tight fit and needs to be measured = for a new smaller piece.  This is a large crack that could easily = be flopping around in flight and somehow interfering with the cooling = process.

9) removed the = quick drain for oil and replaced with the factory plug.  =

I have lots of = clearance and may put the quick drain back = in.

 

The net result is now I have a smooth engine = compartment.   My symptoms

included a difficult propeller balancing as we = could never exactly home in on a solution.  The vibration was small = at 2700 rpm and takeoff but increased significantly with rpm = reduction.  I attribute that to the higher torque twisting the = engine closer to the left side of the baffling.  The vibration was = evident in the cockpit, cowling and when looking at the wings.  The = next project will be to replace the silicone baffle with new material = and replace the circular baffle plate behind the prop and replace the = left side metal baffle to better fit the cowl line near the #5 = cylinder.  Many thanks to all the suggestions that made this easier = to do.

 

Paul Miller

N357V Legacy = RG

 

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