Return-Path: Sender: (Marvin Kaye) To: lml Date: Mon, 16 Dec 2002 21:00:10 -0500 Message-ID: X-Original-Return-Path: Received: from tomts23-srv.bellnexxia.net ([209.226.175.185] verified) by logan.com (CommuniGate Pro SMTP 4.0.2) with ESMTP id 1912622 for lml@lancaironline.net; Mon, 16 Dec 2002 10:59:02 -0500 Received: from a ([67.69.55.127]) by tomts23-srv.bellnexxia.net (InterMail vM.5.01.04.19 201-253-122-122-119-20020516) with SMTP id <20021216155900.UANY22723.tomts23-srv.bellnexxia.net@a> for ; Mon, 16 Dec 2002 10:59:00 -0500 X-Original-Message-ID: <005501c2a51c$a91b4840$7f374543@a> From: "Ian B. Crowe" X-Original-To: "Lancair Mailing List" Subject: LNC Main gear unlocking during taxi X-Original-Date: Mon, 16 Dec 2002 11:03:22 -0500 Organization: Corvi Trade Consultants Inc MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0052_01C2A4F2.BFF153E0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2600.0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 This is a multi-part message in MIME format. ------=_NextPart_000_0052_01C2A4F2.BFF153E0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable Hollis, write in and tell us exactly what you mean by "the main gear = unlocking". I have a feeling you mean something much less disastrous = than the gear over centre link popping up (unlocking) and the gear = folding into the well or partially so. I know that the pump can give the odd burp now and again to maintain the = pressure. This can be due to internal or external leaks, spool valves = in the wrong way or maybe some air in the system. But in my experience = it does not mean that the gear overcentre link has become unlocked, = which would allow the gear to fold. The rat trap spring has to fail to = allow this to happen. I have gauges on my hydraulic system and from my observations it is very = difficult to establish what is happening. Most of the time my system = will behave perfectly, as evidenced by observation of the gear going up = and down. However the odd time, the hydraulic system will push the gear = down perfectly, the pump stops,the low pressure gauge will show a = pressure of 650psi and then it starts to bleed off. The pump cuts in = for less than a second, restores the pressure and the cycle repeats.=20 We had a long discussion on this on the LML. I decided to do nothing = about it as it was not dangerous even if inconvenient and the problem = appears to have faded into the back ground. No burps over the last = month in the hangar or on the taxiway/runway. Maybe it was air or the = infamous back to front shuttle valve. Please tell us Hollis in words of one syllable, if possible, just what = happened when your gear "unlocked". We all badly need to understand = this and must assume the worst until you tell us otherwise. Regards Ian Crowe ------=_NextPart_000_0052_01C2A4F2.BFF153E0 Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable

Hollis, write in and tell us exactly what you mean = by "the=20 main gear unlocking". I have a feeling you mean something much = less=20 disastrous than the gear over centre link popping up = (unlocking) and the=20 gear folding into the well or partially so.

I know that the pump can give the odd burp now and = again to=20 maintain the pressure. This can be due to internal or external = leaks,=20 spool valves in the wrong way or maybe some air in the system. But = in my=20 experience it does not mean that the gear overcentre link has become = unlocked,=20 which would allow the gear to fold. The rat trap spring has to = fail to=20 allow this to happen.

I have gauges on my hydraulic system and from my = observations=20 it is very difficult to establish what is happening. Most of the = time my=20 system will behave perfectly, as evidenced by observation of the gear = going up=20 and down. However the odd time, the hydraulic system will push the = gear=20 down perfectly, the pump stops,the low pressure gauge will show a = pressure of=20 650psi and then it starts to bleed off. The pump cuts in for less = than a=20 second, restores the pressure and the cycle repeats.

We had a long discussion on this on the LML. I = decided=20 to do nothing about it as it was not dangerous even if inconvenient and = the=20 problem appears to have faded into the back ground. No burps over = the last=20 month in the hangar or on the taxiway/runway. Maybe it was air or = the=20 infamous back to front shuttle valve.

Please tell us Hollis in words of one syllable, if = possible,=20 just what happened when your gear "unlocked". We all badly need to = understand this and must assume the worst until you tell us=20 otherwise.

Regards

Ian Crowe

------=_NextPart_000_0052_01C2A4F2.BFF153E0--