X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml Date: Sun, 10 Sep 2006 12:39:15 -0400 Message-ID: X-Original-Return-Path: Received: from web61318.mail.yahoo.com ([209.73.179.72] verified) by logan.com (CommuniGate Pro SMTP 5.1c.3) with SMTP id 1372694 for lml@lancaironline.net; Sun, 10 Sep 2006 12:09:02 -0400 Received-SPF: none receiver=logan.com; client-ip=209.73.179.72; envelope-from=charliekohler@yahoo.com Received: (qmail 47204 invoked by uid 60001); 10 Sep 2006 16:08:22 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=Message-ID:Received:Date:From:Reply-To:Subject:To:In-Reply-To:MIME-Version:Content-Type; b=RdbjcuhaY3IF6Wg+dx5AgMSrgpl44F9lul5I94KsMNUDwfb9wrhVzvmra8BvYwmNvKEPmJOrT0qT0T+tUh/4vLwN9tVMJtcGAlalahyO1gZdoYbNC8r7OLc2N/ao7prfdIeFVKOpr1TkdYJHVT2frMs/k6nscVJ16gtGoCzehFE= ; X-Original-Message-ID: <20060910160822.47202.qmail@web61318.mail.yahoo.com> Received: from [68.202.95.219] by web61318.mail.yahoo.com via HTTP; Sun, 10 Sep 2006 09:08:21 PDT X-Original-Date: Sun, 10 Sep 2006 09:08:21 -0700 (PDT) From: Charlie Kohler Reply-To: Charlie Kohler Subject: Re: [LML] Landing Gear retract X-Original-To: Lancair Mailing List In-Reply-To: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="0-1748963885-1157904501=:45302" --0-1748963885-1157904501=:45302 Content-Type: text/plain; charset=us-ascii Hi Art, The cause of the main landing gear not coming up --99% of the time-- is that the door is not open far enough to clear the brake pad bolts. And the door is flexible enough to bend outwardly until the tip of the door will touch the brake pad bolts. You can see if this is the case by looking for nicks in the door composite material at the very tip of the door. If the material is chipped--look no further. But if it's inconclusive I would suggest putting a layer of duct tape or wide masking tape around the edge of that door and flying the airplane. If the gear does not come up it should leave an indelible impression in the tape so that you know exactly where it is hitting. You can also test on the ground by doing a retraction test and bringing the gear up to the point where it is about 2 feet out of the well. At that point--by hand with the pump off-- push the gear door outward-- as hard as you can-- and retracting (pushing) the gear up to see if it will hang up on the bolts mentioned. If it does then you would not need to fly it. The cure; Number 1- stiffen the door. More carbon in the slider strip mount. Check the service bulletin on the subject. Aluminum tube bedded in carbon works well. Just make sure there's no interference with the gear up. Number 2 -- open the door further by increasing the height of the poly slider strip. This may cause a problem by the two doors hitting and the trap door interfering with the other gear door. #3 -- if you have Clearence between the tire and the outer fuselage skin as the wheel goes into the wheel well, you can put a spacer shim under the axle to move the tire outboard. This is the least likely option, because the tire will arc out beyond the edge of the fuselage. But it would be my first choice IF there is room. Send some pictures and I'll help you further if you like. Charlie K. Charlie K. ----- Original Message ---- From: Art Bertolina To: Lancair Mailing List Sent: Saturday, September 9, 2006 11:38:55 PM Subject: [LML] Landing Gear retract I have a total of 45 hrs on my L IV and in that time(accumulated since July 8th this year) I have on several occasions had the gear not come up after take-off I was under the assumption that it was probable because I was a little over 120kts and slowed down and recycled the gear and they would come up fine. On Sept. 1st took-off to fly to Redmond and the gear would not come up after 3 tries, I landed and put the plane away and drove. On my return I jacked the plane up and cycled the gear 6 times and they worked fine, someone listening to the hydraulic pump said it sounded like it was not producing enough pressure so I turned up the pressure until I could hear the pump lug down more toward the end of the cycle and it ran longer as well. I flew again today to test the gear and the gear would not come up my 3 green gear down lights went out (where as on the 1st the left main gear light stayed on) but was confirmed from the ground that the nose gear did retract but the main just seem to hang straight down but would not come up into the wheel wells. I would appreciate any ideas or thoughts. Regards Art --0-1748963885-1157904501=:45302 Content-Type: text/html; charset=us-ascii

Hi Art,

The cause of the main landing gear not coming up --99% of the time-- is that the door is not open far enough to clear the brake pad bolts. And the door is flexible enough to bend outwardly until the tip of the door will touch the brake pad bolts. You can see if this is the case by looking for nicks in the door composite material at the very tip of the door. If the material is chipped--look no further. But if it's inconclusive I would suggest putting a layer of duct tape or wide masking tape around the edge of that door and flying the airplane. If the gear does not come up it should leave an indelible impression in the tape so that you know exactly where it is hitting.

You can also test on the ground by doing a retraction test and bringing the gear up to the point where it is about 2 feet out of the well. At that point--by hand with the pump off-- push the gear door outward-- as hard as you can-- and retracting (pushing) the gear up to see if it will hang up on the bolts mentioned. If it does then you would not need to fly it.

The cure;

Number 1- stiffen the door. More carbon in the slider strip mount. Check the service bulletin on the subject. Aluminum tube bedded in carbon works well. Just make sure there's no interference with the gear up.

Number 2 -- open the door further by increasing the height of the poly slider strip. This may cause a problem by the two doors hitting and the trap door interfering with the other gear door.

#3 -- if you have Clearence between the tire and the outer fuselage skin as the wheel goes into the wheel well, you can put a spacer shim under the axle to move the tire outboard. This is the least likely option, because the tire will arc out beyond the edge of the fuselage. But it would be my first choice IF there is room.

Send some pictures and I'll help you further if you like.

Charlie K.


 
Charlie K.


----- Original Message ----
From: Art Bertolina <artbertolina@earthlink.net>
To: Lancair Mailing List <lml@lancaironline.net>
Sent: Saturday, September 9, 2006 11:38:55 PM
Subject: [LML] Landing Gear retract

I have a total of 45 hrs on my L IV and in that time(accumulated since July 8th this year) I have on several
occasions had the gear not come up after take-off I was
under the assumption that it was probable because I was
a little over 120kts and slowed down and recycled the
gear and they would come up fine. On Sept. 1st took-off
to fly to Redmond and the gear would not come up after
3 tries, I landed and put the plane away and drove. On my
return I jacked the plane up and cycled the gear 6 times
and they worked fine, someone listening to the hydraulic
pump said it sounded like it was not producing enough
pressure so I turned up the pressure until I could hear the
pump lug down more toward the end of the cycle and it
ran longer as well. I flew again today to test the gear and
the gear would not come up my 3  green gear down lights
went out (where as on the 1st the left main gear light stayed
on) but was confirmed from the ground that the nose gear 
did retract but the main just seem to hang straight down but would not come up into the wheel wells. I would
appreciate any ideas or thoughts.
Regards
Art  
        

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