X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Mon, 16 Aug 2010 08:43:24 -0400 Message-ID: X-Original-Return-Path: Received: from asmtpout022.mac.com ([17.148.16.97] verified) by logan.com (CommuniGate Pro SMTP 5.3.8) with ESMTP id 4431899 for lml@lancaironline.net; Sun, 15 Aug 2010 19:04:23 -0400 Received-SPF: pass receiver=logan.com; client-ip=17.148.16.97; envelope-from=steve.veach@mac.com MIME-version: 1.0 Content-type: multipart/alternative; boundary="Boundary_(ID_tdqepFJGaF+iHuw5Dun9CA)" Received: from [192.168.1.66] (adsl-21-212-13.mem.bellsouth.net [66.21.212.13]) by asmtp022.mac.com (Sun Java(tm) System Messaging Server 6.3-8.01 (built Dec 16 2008; 32bit)) with ESMTPSA id <0L7700EFKUPX7400@asmtp022.mac.com> for lml@lancaironline.net; Sun, 15 Aug 2010 16:03:35 -0700 (PDT) X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 ipscore=0 phishscore=0 bulkscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx engine=6.0.2-1004200000 definitions=main-1008150178 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.0.10011,1.0.148,0.0.0000 definitions=2010-08-15_08:2010-08-15,2010-08-15,1970-01-01 signatures=0 X-Original-Message-id: From: Steve Veach X-Original-To: lml@lancaironline.net Subject: LNC2 Over Center Link X-Original-Date: Sun, 15 Aug 2010 18:03:33 -0500 X-Mailer: Apple Mail (2.936) --Boundary_(ID_tdqepFJGaF+iHuw5Dun9CA) Content-type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Content-transfer-encoding: 7BIT Thanks Grayhawk, Would you say most guys leave the gear down when they're in the pattern? Steve Steve, There are many 320/360 Lancairs operating with the original link. Assuming the nose gear mounting blocks and spacer allow proper operation, the main problem can occur at the nose-gear-tab and final over-center-link connecting bolt since the bolt-tab-link are bearing surfaces. The problem shows itself as looseness of this connection that can lead to failure. Think about operating on rough surfaces and the beating that this connection would take as it becomes looser and looser. 0. Rigging - the gas spring should exert enough pressure that one should have to muscle the last half inch of the raising the link assembly to allow the bolt to go through it and the tab. The nose gear actuator must reach its own physical stop without putting undue pressure on the link - it should just stop the link from coming undone when over center. Excess pressure can lead to failure - especially at the top of the nose gear wheel well where the actuator is attached. 1. At each annual the looseness condition can be checked while the aircraft is on jacks by wiggling the nose gear fwd and aft. It shouldn't wiggle. 2. The bolt length specified by Lancair is too short and bolt threads can quickly wear down against the tab hole. Using extra washers, make sure the body of the bolt is bearing on both tabs. Replace this bolt if it becomes worn (excessive practice landings ;-)). 3. Of course, one should be using a drilled bolt and castle nut since the bolt may turn. It should be only tightened enough that there is no added friction between the tab and link. 4. Keep this joint lubricated -- I am fortunate (?) that my engine produces a minor nuisance oil leak - just enough to keep the nose gear system oily. Grayhawk --Boundary_(ID_tdqepFJGaF+iHuw5Dun9CA) Content-type: text/html; charset=US-ASCII Content-transfer-encoding: quoted-printable

Thanks Grayhawk,

Would you say most guys = leave the gear down when they're in the pattern?

Steve

Steve,

There are many = 320/360 Lancairs operating with the original link. Assuming = the nose gear mounting blocks and spacer allow proper operation, the = main problem can occur at the nose-gear-tab and final = over-center-link connecting bolt since the bolt-tab-link are bearing = surfaces. The problem shows itself as looseness of this = connection that can lead to failure. Think about operating on = rough surfaces and the beating that this connection would take = as it becomes looser and looser.

0. Rigging - the gas spring should exert enough = pressure that one should have to muscle the last half inch of the = raising the link assembly to allow the bolt to go through it and = the tab. The nose gear actuator must reach its own physical = stop without putting undue pressure on the link - it should just stop = the link from coming undone when over center. Excess pressure can = lead to failure - especially at the top of the nose gear wheel well = where the actuator is attached.

1. At each annual the looseness condition = can be checked while the aircraft is on jacks by wiggling the nose = gear fwd and aft. It shouldn't = wiggle.

2. The bolt length specified by = Lancair is too short and bolt threads can quickly wear = down against the tab hole. Using extra washers, make sure the = body of the bolt is bearing on both tabs. Replace this bolt if it = becomes worn (excessive practice landings = ;-)).

3. Of course, one should = be using a drilled bolt and castle nut since the bolt may = turn. It should be only tightened enough that there is no added = friction between the tab and link.

4. = Keep this joint lubricated -- I am fortunate (?) that my engine = produces a minor nuisance oil leak - just enough to keep the nose gear = system = oily.

Grayhawk

= --Boundary_(ID_tdqepFJGaF+iHuw5Dun9CA)--