X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Tue, 16 Jun 2009 19:15:46 -0400 Message-ID: X-Original-Return-Path: Received: from mailrelay.embarq.synacor.com ([208.47.184.3] verified) by logan.com (CommuniGate Pro SMTP 5.2.14) with ESMTP id 3683965 for lml@lancaironline.net; Tue, 16 Jun 2009 07:24:54 -0400 Received-SPF: pass receiver=logan.com; client-ip=208.47.184.3; envelope-from=liegner@embarqmail.com X-Original-Return-Path: X-BINDING: X-Spam-Rating: None X_CMAE_Category: 0,0 Undefined,Undefined X-CNFS-Analysis: v=1.0 c=1 a=7y-PJpYwLlYA:10 a=M9rYfVNsTseKEFYX9CUA:9 a=gi2IW8lNtACDl8pl4Oc0bBimfMQA:4 a=8s33dsPJhHHVEMXb4dkA:9 a=HEtXtAtgWazce0fjF5EA:7 a=DSodc7A5b-H43MzAH3ILNMXf8agA:4 X-CM-Score: 0 X-Scanned-by: Cloudmark Authority Engine Authentication-Results: smtp02.embarq.synacor.com smtp.user=liegner@embarqmail.com; auth=pass (LOGIN) Received: from [65.41.246.32] ([65.41.246.32:14283] helo=[172.16.1.2]) by mailrelay.embarq.synacor.com (envelope-from ) (ecelerity 2.2.2.40 r(29895/29896)) with ESMTPA id 30/CA-25045-2E0873A4; Tue, 16 Jun 2009 07:24:19 -0400 Mime-Version: 1.0 X-Sender: liegner@embarqmail.com@pop.embarqmail.com X-Original-Message-Id: In-Reply-To: References: X-Original-Date: Tue, 16 Jun 2009 06:43:04 -0400 X-Original-To: "Lancair Mailing List" From: "Jeffrey Liegner, MD" Subject: Re: Continuous running hydraulic pump Content-Type: multipart/alternative; boundary="============_-966971037==_ma============" --============_-966971037==_ma============ Content-Type: text/plain; charset="us-ascii" ; format="flowed" More observation: If I leave my flap lever in the neutral position, the hydralic reservoir remains fully pressurized, and next time I fly there's no need for the pump to come on during power up to recharge the system. I understand that some planes/pilots must leave their flap lever in the UP position, or the DOWN position to retain hydralic pressure until the next flight. If I did this, all pressure would be released. Why the difference with what is the same valve? I also have seen the flaps move (briefly) in the opposite direction if lever is positioned just slightly off of neutral, during routine operations; I agree that this is a quirk in the internal valve. Jeff Liegner LIVP >This is case of creating a problem that wasn't there. My experience >might ease someone's tension in the future. > >While practicing an approach I got a "check engine" from the >Chelton. The indication was low voltage. I quickly saw the >hydraulic pump was running continuously. I pulled the hydraulic >pump breaker. I got a "gear transition" light so I suspected no >hydraulic pressure which was confirmed when I looked at the gauge. > >I figured the best thing to do was to leave everything as it was and >hand pump the gear down and land. This worked just fine. > >Now the problem was that for the first time in over 600 hours of >flying this thing, when I had set the flaps at 10 degrees I had left >the flap handle a little out of the detent and the valve was just >dumping the high side pressure to the low side and just kept the >hydraulic pump running. > >Some days I think that if every thing is going well I just create a >problem for the practice. At least my rebuild of the gear hand pump >worked well. > >Dan Reagan >IVP 650 hours --============_-966971037==_ma============ Content-Type: text/html; charset="us-ascii" Re: Continuous running hydraulic pump
More observation:
If I leave my flap lever in the neutral position, the hydralic reservoir remains fully pressurized, and next time I fly there's no need for the pump to come on during power up to recharge the system.

I understand that some planes/pilots must leave their flap lever in the UP position, or the DOWN position to retain hydralic pressure until the next flight.  If I did this, all pressure would be released.  Why the difference with what is the same valve?

I also have seen the flaps move (briefly) in the opposite direction if lever is positioned just slightly off of neutral, during routine operations; I agree that this is a quirk in the internal valve.

Jeff Liegner
LIVP


This is case of creating a problem that wasn't there.  My experience might ease someone's tension in the future.
 
While practicing an approach I got a "check engine" from the Chelton.  The indication was low voltage.  I quickly saw the hydraulic pump was running continuously.  I pulled the hydraulic pump breaker.  I got a "gear transition" light so I suspected no hydraulic pressure which was confirmed when I looked at the gauge.
 
I figured the best thing to do was to leave everything as it was and hand pump the gear down and land.  This worked just fine.
 
Now the problem was that for the first time in over 600 hours of flying this thing, when I had set the flaps at 10 degrees I had left the flap handle a little out of the detent and the valve was just dumping the high side pressure to the low side and just kept the hydraulic pump running.
 
Some days I think that if every thing is going well I just create a problem for the practice.  At least my rebuild of the gear hand pump worked well.
 
Dan Reagan
IVP 650 hours

--============_-966971037==_ma============--