X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 20 Feb 2013 08:21:32 -0500 Message-ID: X-Original-Return-Path: Received: from mail-wg0-f45.google.com ([74.125.82.45] verified) by logan.com (CommuniGate Pro SMTP 6.0.1) with ESMTPS id 6072917 for lml@lancaironline.net; Tue, 19 Feb 2013 20:54:45 -0500 Received-SPF: pass receiver=logan.com; client-ip=74.125.82.45; envelope-from=indigoaviation@gmail.com Received: by mail-wg0-f45.google.com with SMTP id dq12so6219092wgb.24 for ; Tue, 19 Feb 2013 17:54:11 -0800 (PST) MIME-Version: 1.0 X-Received: by 10.180.103.161 with SMTP id fx1mr31084468wib.25.1361325251652; Tue, 19 Feb 2013 17:54:11 -0800 (PST) Received: by 10.194.177.234 with HTTP; Tue, 19 Feb 2013 17:54:11 -0800 (PST) In-Reply-To: References: X-Original-Date: Tue, 19 Feb 2013 20:54:11 -0500 X-Original-Message-ID: Subject: Re: [LML] Re: IV nose gear From: swaid rahn X-Original-To: Lancair Mailing List Content-Type: multipart/alternative; boundary=f46d044288920c6dba04d61e3c67 --f46d044288920c6dba04d61e3c67 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable Probably an unrelated problem but something that should be checked. At one of the annuals the gear would not fully lock on an emer. extension. We have the larger long cyl. accumulator and I found that it was over serviced with Nitrogen to 800psi. Once I lowered it to 600psi it started working properly. I'm guessing that the higher psi would not let enough fluid in the cyl. and therefore ran out of fluid on the extension push. Swaid On Tue, Feb 19, 2013 at 6:35 PM, Robert R Pastusek wrot= e: > Carl wrote: **** > > ** ** > > Today on takeoff from Leesburg Fl on a trip back to Ann Arbor MI the towe= r > controller informed me that one of my landing gear was not retracted. > Checked the indicator lights and sure enough the nose gear light was > indicating down and locked- but the mains had retracted normally. I cycle= d > the gear down at about 150 kts (3 green), then back up as I climbed out. > Still nose gear down and locked=85 Slowed to 125, my usual gear down spe= ed, > cycled the gear down, 3 green. Retracted gear, all three came up as usual= . > **** > > ** ** > > Anyone had a problem like this before? I checked over the gear after > landing and everything looks normal. Plan to put it on jacks and swing th= e > gear before flying again but any ideas on this one would be appreciated. = * > *** > > ** ** > > We replaced the gas strut at annual in October, simply because it had bee= n > in use for about 10 years. We also replaced the hydraulic cylinder end an= d > did the over center link mod per service bulletin SB074-0111. Did gear > swing after that work, all fine. Have done about 15 landings since the > October annual.**** > > ** ** > > Carl Loomis**** > > ** ** > > Carl,**** > > ** ** > > I have not heard of this occurrence before, but it sounds like either a > restricted/galled nose actuator or significant friction/binding in the no= se > gear retract mechanism. Bending of the linkage/actuator rod/etc is a > classic cause of this, but is not common at all within the IV-IV/P fleet. > In any case, this is not something to mess around with=97if any of these > things are the cause, a failure to extend is as likely as a failure to > retract! By the way, increased airspeed will slow/can limit the extension > of your gear, especially emergency extension, but not retraction. Ditto f= or > a defective gas spring/air strut. **** > > **** > > If it were mine, I=92d put the plane on jacks, disconnect the gas spring = and > the actuator cylinder and check the hinges/folding links for binding. You > can also raise/lower the gear while on jacks and with the nose gear > actuator disconnected, but for a completely valid check, I=92d then remov= e > the actuator and inspect the inside carefully after the functional test. > I=92ll send you Chris Zavatson=92s excellent article about > disassembling/servicing the actuator by separate email.**** > > **** > > I can=92t think of any other possibilities, given that it=92s worked befo= re, > and did so again after three tries=85 During normal operation, my nose ge= ar > always extends and retracts first, with the mains being slower to both > extend fully and to retract fully. > > Bob**** > > ** ** > --f46d044288920c6dba04d61e3c67 Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: quoted-printable
Probably an unrelated problem but something that should be checked. At= one of the annuals the gear would not fully lock on an emer. extension. We= have the larger long cyl. accumulator and=A0I found that it was over servi= ced with Nitrogen to 800psi. Once I lowered it to 600psi it started working= properly. I'm guessing that the higher psi would not let enough fluid = in the cyl. and therefore ran out of fluid on the extension push.
Swaid

On Tue, Feb 19, 2013 at = 6:35 PM, Robert R Pastusek <rpastusek@htii.com> wrote:
<= blockquote style=3D"margin:0px 0px 0px 0.8ex;padding-left:1ex;border-left-c= olor:rgb(204,204,204);border-left-width:1px;border-left-style:solid" class= =3D"gmail_quote">

Carl wrote:

=A0

Today on takeoff from Leesburg Fl on a trip back to = Ann Arbor MI the tower controller informed me that one of my landing gear w= as not retracted. Checked the indicator lights and sure enough the nose gea= r light was indicating down and locked- but the mains had retracted normally. I cycled the gear down at about 150 = kts (3 green), then back up as I climbed out. Still nose gear down and lock= ed=85=A0 Slowed to 125, my usual gear down speed, cycled the gear down, 3 g= reen. Retracted gear, all three came up as usual.

=A0

Anyone had a problem like this before? I checked ove= r the gear after landing and everything looks normal. Plan to put it on jac= ks and swing the gear before flying again but any ideas on this one would b= e appreciated.

=A0

We replaced the gas strut at annual in October, simp= ly because it had been in use for about 10 years. We also replaced the hydr= aulic cylinder end and did the over center link mod per service bulletin SB= 074-0111. Did gear swing after that work, all fine. Have done about 15 landings since the October annual.

=A0

Carl Loomis

=A0

Carl,=

=A0

I have not hear= d of this occurrence before, but it sounds like either a restricted/galled = nose actuator or significant friction/binding in the nose gear retract mech= anism. Bending of the linkage/actuator rod/etc is a classic cause of= this, but is not common at all within the IV-IV/P fleet. In any case, this= is not something to mess around with=97if any of these things are the caus= e, a failure to extend is as likely as a failure to retract! By the way, increased airspeed will = slow/can limit the extension of your gear, especially emergency extension, = but not retraction. Ditto for a defective gas spring/air strut.

=A0

If it were mine= , I=92d put the plane on jacks, disconnect the gas spring and the actuator = cylinder and check the hinges/folding links for binding. You can also raise= /lower the gear while on jacks and with the nose gear actuator disconnected, but = for a completely valid check, I=92d then remove the actuator and inspect th= e inside carefully after the functional test. I=92ll send you Chris Zavatson=92s excellent article about disassembling/servicing t= he actuator by separate email.

=A0

I can=92t think= of any other possibilities, given that it=92s worked before, and did so ag= ain after three tries=85 During normal operation, my nose gear always exten= ds and retracts first, with the mains being slower to both extend fully and to re= tract fully.

Bob

=A0


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