X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Sun, 03 May 2009 17:00:52 -0400 Message-ID: X-Original-Return-Path: Received: from imr-d01.mx.aol.com ([205.188.157.39] verified) by logan.com (CommuniGate Pro SMTP 5.2.14) with ESMTP id 3620284 for lml@lancaironline.net; Sat, 02 May 2009 07:42:28 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.188.157.39; envelope-from=Sky2high@aol.com Received: from imo-ma03.mx.aol.com (imo-ma03.mx.aol.com [64.12.78.138]) by imr-d01.mx.aol.com (v107.10) with ESMTP id RELAYIN3-449fc315a8c; Sat, 02 May 2009 07:41:15 -0400 Received: from Sky2high@aol.com by imo-ma03.mx.aol.com (mail_out_v40_r1.5.) id q.c90.4145728a (29679) for ; Sat, 2 May 2009 07:40:59 -0400 (EDT) From: Sky2high@aol.com X-Original-Message-ID: X-Original-Date: Sat, 2 May 2009 07:40:59 EDT Subject: Re: [LML] LNC2 gear X-Original-To: lml@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-----------------------------1241264459" X-Mailer: AOL 9.1 sub 5006 X-Spam-Flag:NO X-AOL-IP: 64.12.78.138 -------------------------------1241264459 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Terrence, The new information does not change my analysis. The following would be added to it: If the dump valve is closed (no cross connection between the up-side and the down-side), then any attempt to hand raise the nose would mean that pressure would be placed on the down-side since there is no place for that fluid to go - Indeed, the down-side pressure would be increased on the main gear actuators rather than decreased. Any fluid needed to fill the up-side would come thru the pump and reservoir since that is the only possible source - assuming everything is as designed. Once you open the dump valve, I stand by my analysis. If you think that your action while the dump valve was closed (pushing on the nose over center link) caused the main over center links to come unlocked, you have a serious problem with your hydraulic system and the springs that hold the main gear over center links in place. Scott Krueger In a message dated 5/1/2009 3:27:54 P.M. Central Daylight Time, troneill@charter.net writes: Typo one-=line correction to my last on the gar... line 5... correction underlined. ----- Original Message ----- From: _terrence o'neill_ (mailto:troneill@charter.net) To: _lml@lancaironline.net_ (mailto:lml@lancaironline.net) Sent: Thursday, April 30, 2009 18:55 Subject: [LML] LNC2 gear Here's an interesting quirk of the retract system, I think.... Yesterday, spurred by a helpful LML suggestion to increase the preload in my nose strut, I chocked the mains, weighted the tail, and supported the nose with the nosewheel an inch off the ground, in order to rotate the nosegear up a little in order to get an air chuck on the schroeder valve less than an inch behnd #3 exhaust tube. So I pushed up the over- -center brace and pushed back the strut which moved back a little... which reisted .... still locked up. So I opened the free-fall valve. Pushed back the nose strut, chucked my new $22. / 300 psi made-in-china strut pump, on, and put in the max. Then lowered the nosewheel to over-center lock, lowered the nose, removed the weight on the tail, and observed 3 inches of strut! So I pulled the plane out to run an engine idle check, and glanced at the right wing, was shocked to see the gear leaning inward about 10 degrees. ! I managed to get the jack in place and raise the wing enough to push the gear in place and pull the over-center strut to lock. Checked the left gear... and found its over-center strut pushed up, unlocked, too! Jacked and pulled it down, and then put the plane back in the hangar and ran a retract-extend check -- after putting the free-fall valve back in closed position. My guess is that with the hydraulic system closed/normal, in pushing the nosegear over-center lock up and pushing back on the nosewheel I also hydraulic-pressured the main cylinders to pull their over-center locks up. So, if this is true, then here's a scenario to consider: Gear down, no nose green light. System pump or solenoid CB pops. SO, pull the pump CB, gear switch in Down, valve to free-fall. Still can't get a nose green light. Just the mains. To land, should the free-fall valve be left open, or moved to closed? If it is moved to closed, and the nosegear is not locked over-center... will aft pressure on touchdown unlock the mains too, damaging not only the prop/engine but also the gear and fuselage? Terrence L235/320 N211AL No virus found in this outgoing message Checked by PC Tools AntiVirus (5.0.0.22 - 10.100.057). _http://www.pctools.com/free-antivirus/_ (http://www.pctools.com/free-antivirus/) No virus found in this incoming message Checked by PC Tools AntiVirus (5.0.0.22 - 10.100.057). _http://www.pctools.com/free-antivirus/_ (http://www.pctools.com/free-antivirus/) No virus found in this outgoing message Checked by PC Tools AntiVirus (5.0.0.22 - 10.100.057). _http://www.pctools.com/free-antivirus/_ (http://www.pctools.com/free-antivirus/) **************Eat Great & Lose Weight FASTER! Start the South Beach Diet Online - FREE Profile! (http://pr.atwola.com/promoclk/100126575x1221822996x1201398599/aol?redir=http:%2F%2Fad.doubleclick.net%2Fclk%3B213623126%3B35100424% 3Bk) -------------------------------1241264459 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
Terrence,
 
The new information does not change my analysis.  The following= would be added to it:
 
If the dump valve is closed (no cross connection between the up-side= and the down-side), then any attempt to hand raise the nose would mean that pr= essure would be placed on the down-side since there is no place for that fluid to= go - Indeed, the down-side pressure would be increased on the main gear actuato= rs rather than decreased.  Any fluid needed to fill the up-sid= e would come thru the pump and reservoir since that is the only possible sou= rce - assuming everything is as designed.
 
Once you open the dump valve, I stand by my analysis.
 
If you think that your action while the dump valve was closed (pushin= g on the nose over center link) caused the main over center links to come= unlocked, you have a serious problem with your hydraulic system and the sp= rings that hold the main gear over center links in place.
 
Scott Krueger
 
In a message dated 5/1/2009 3:27:54 P.M. Central Daylight Time, troneill@charter.net writes:
Typo one-=3Dline co= rrection to my last on the gar... line 5... correction underlined.
----- Original Message -----
Sent: Thursday, April 30, 2009= 18:55
Subject: [LML] LNC2 gear

Here's an interes= ting quirk of the retract system, I think....
Yesterday, spurre= d by a helpful LML suggestion to increase the preload in my nose strut, I cho= cked the mains, weighted the tail, and supported the nose with the nosewhee= l an inch off the ground, in order to rotate the nosegear up a little in or= der to get an air chuck on the schroeder valve less than an inch behnd= #3 exhaust tube.
So I pushed up th= e over- -center brace and pushed back the strut which moved back a little..= . which reisted .... still locked up. So I opened the free= -fall valve. Pushed back the nose strut, chucked my new $22. / 300 psi= made-in-china strut pump, on, and put in the max. 
Then lowered the= nosewheel to over-center lock, lowered the nose, removed the weight on the tail, and= observed 3 inches of strut!
So I pulled the= plane out to run an engine idle check, and glanced at the right wing, was shocke= d to see the gear leaning inward about 10 degrees. !
 
I managed to get= the jack in place and raise the wing enough to push the gear in place and pull= the over-center strut to lock.
Checked the left= gear... and found its over-center strut pushed up, unlocked,  too!=
Jacked and pulled= it down, and then put the plane back in the hangar and ran a retract-extend che= ck -- after putting the free-fall valve back in closed position.
My guess is that= with the hydraulic system closed/normal, in pushing the nosegear over-= center lock up and pushing back on the nosewheel I also hydraulic-pressured= the main cylinders to pull their over-center locks up.
 
So, if this= is true, then here's a scenario to consider:
Gear down, no nos= e green light.
System pump= or solenoid CB pops. 
SO, pull the pump= CB, gear switch in Down, valve to free-fall.
Still can't get= a nose green light. Just the mains.
 
To land, should= the free-fall valve be left open,  or moved to closed? 
 
If it is moved to= closed, and the nosegear is not locked over-center... will aft= pressure on touchdown unlock the mains too, damaging not only the prop/engine but also the gear and fuselage?
 
Terrence
L235/320 N211AL


No virus found in this outgoing message
Checked by PC Tools AntiVirus (5.0.0.22 - 10.100.057).
<= A title=3Dhttp://www.pctools.com/free-antivirus/ href=3D"http://www.pctools.com/free-antivirus/">http://www.pctools.com= /free-antivirus/


No virus found in this incoming message
Checked by PC Tools AntiVirus= (5.0.0.22 - 10.100.057).
http://www.pctools.com= /free-antivirus/


No virus found in this outgoing message
Checked by PC Tools AntiVirus (5.0.0.22 - 10.100.057).
http://www.pctools.com/f= ree-antivirus/

Eat Great & Lose Weight FASTER! Start the South Beach Diet= Online - FREE Profile! -------------------------------1241264459--