X-Virus-Scanned: clean according to Sophos on Logan.com X-SpamCatcher-Score: 2 [X] Return-Path: Sender: To: lml@lancaironline.net Date: Sun, 22 Apr 2007 17:26:39 -0400 Message-ID: X-Original-Return-Path: Received: from imo-d05.mx.aol.com ([205.188.157.37] verified) by logan.com (CommuniGate Pro SMTP 5.1.8) with ESMTP id 1998799 for lml@lancaironline.net; Sun, 22 Apr 2007 13:06:58 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.188.157.37; envelope-from=Sky2high@aol.com Received: from Sky2high@aol.com by imo-d05.mx.aol.com (mail_out_v38_r8.1.) id q.c09.163b0a96 (41810) for ; Sun, 22 Apr 2007 13:05:29 -0400 (EDT) From: Sky2high@aol.com X-Original-Message-ID: X-Original-Date: Sun, 22 Apr 2007 13:05:29 EDT Subject: Re: [LML] L360 Nose Gear Collapse, The Adventure, The Cause X-Original-To: lml@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-----------------------------1177261529" X-Mailer: 9.0 Security Edition for Windows sub 5365 X-Spam-Flag: NO -------------------------------1177261529 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 4/22/2007 10:37:31 A.M. Central Daylight Time, LHenney@charter.net writes: The T Boss attach point appears to be the primary initiator of the failure sequence. Upon close inspection, the 3/8" pivot rod had been rotating with the moving piece (read, lack of lube). The cotter key in cockpit was found in pieces (under the EAR stick on insulation- who knows why I tolerated that invisibility.... out of site out of mind..) Anyway, the rod appears to have been easing it's way West for several gear cycles. The little bump into the irrigation line trench appears to have been the last straw allowing the East end of the rod to swing freely with the help of the nitrogen strut and bend the 3/8" pivot, unleashing all manor of devilish forces. The fix.... May be nothing in your case. I believe larger cotter keys, inspection, and annual lubrication would have eliminated the problem. I seem to remember not knowing much about drilling stainless back in the day. My cotter key was a wee little piece. However, there are at least two additional things I am going to do to repair mine. First, I'll add a grease zirt to the T Boss part so I can get lube to the 3/8" bushings. Additionally, I'll use a roll pin on one end of the 3/8" pivot rod. In conjunction with the roll pin will be a slotted mating piece of phenolic. This will eliminate any possibility of the axle ever turning. Larry, Sorry for the results you suffered from the inactivity of your HOA. Surely they have dirty hands in this cruel mishap. Oops, I didn't want to sling mud into an open wound. Your analysis and descriptions are very useful - and frightening. Interestingly, during the last century when I was building, I also though that a Zerk fitting would be an important addition to that crucial pivot. Alas, the thing would have required disassembly and I didn't know about McMaster-Carr at the time. What I did notice was the thru rod binding because of the welding distortions on the T-pivot piece tube. I sort of reamed mine out to reduce the binding. Gulp! I have not lubricated that area in the last 5 years. Of course, my engine does have just enough leaks to provide the nose wheel well with a fine coating of motor oil. Now for the frightening part. My through rod is secured like yours and others. It also hides behind the foot well interior lining. I think I will pull the lining back and take a look at what is happening with the rod at the termination points. Uh, it will be a good way to finish up my annual even though I signed it off just last week. Scott Krueger AKA Grayhawk Lancair N92EX IO320 SB 89/96 Aurora, IL (KARR) Darwinian culling phrase: Watch This! ************************************** See what's free at http://www.aol.com. -------------------------------1177261529 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
In a message dated 4/22/2007 10:37:31 A.M. Central Daylight Time,=20 LHenney@charter.net writes:
<= FONT=20 style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size= =3D2>
The T Bo= ss attach=20 point appears to be the primary initiator of the failure=20 sequence.  Upon close inspection, the 3/8" pivot rod had been=20 rotating with the moving piece (read, lack of lube).  The cotter key=20= in=20 cockpit was found in pieces (under the EAR stick on insulation- who knows=20= why=20 I tolerated that invisibility.... out of site out of mind..) Anyway, the r= od=20 appears to have been easing it's way West for several gear cycles.  T= he=20 little bump into the irrigation line trench appears to have been the last=20 straw allowing the East end of the rod to swing freely with the help of th= e=20 nitrogen strut and bend the 3/8" pivot, unleashing all manor of devilish=20 forces.
 
The fix.= ... =20 May be nothing in your case.  I believe larger cotter keys, inspectio= n,=20 and annual lubrication would have eliminated the problem. =20= I=20 seem to remember not knowing much about drilling stainless back in the=20 day.  My cotter key was a wee little piece.  However, there are=20= at=20 least two additional things I am going to do to repair mine.  First,=20= I'll=20 add a grease zirt to the T Boss part so I can get lube to the 3/8"=20 bushings.  Additionally, I'll use a roll pin on one end of the 3= /8"=20 pivot rod.  In conjunction with the roll pin will be a slotted mating= =20 piece of phenolic.  This will eliminate any possibility of the a= xle=20 ever turning.
Larry,
 
Sorry for the results you suffered from the inactivity of your=20 HOA.  Surely they have dirty hands in this cruel mishap.  Oops, I=20 didn't want to sling mud into an open wound.
 
Your analysis and descriptions are very useful - and frightening. = =20 Interestingly, during the last century when I was building, I also though th= at a=20 Zerk fitting would be an important addition to that crucial pivot.  Ala= s,=20 the thing would have required disassembly and I didn't know about McMaster-C= arr=20 at the time.  What I did notice was the thru rod binding because of the= =20 welding distortions on the T-pivot piece tube.  I sort of reamed m= ine=20 out to reduce the binding.  Gulp! I have not lubricated that area in th= e=20 last 5 years.  Of course, my engine does have just enough lea= ks=20 to provide the nose wheel well with a fine coating of motor oil.
 
Now for the frightening part.  My through rod is secured like your= s=20 and others.  It also hides behind the foot well interior lining. =20= I=20 think I will pull the lining back and take a look at what is happening with=20= the=20 rod at the termination points.  Uh, it will be a good way to finish up=20= my=20 annual even though I signed it off just last week.=20
 
Scott Krueger=20 AKA Grayhawk
Lancair N92EX IO320 SB 89/96
Aurora, IL=20 (KARR)

Darwinian culling phrase: Watch=20 This!



See wha= t's free at AOL.co= m.
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