X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 21 Aug 2013 08:10:51 -0400 Message-ID: X-Original-Return-Path: Received: from omr-m06.mx.aol.com ([64.12.143.80] verified) by logan.com (CommuniGate Pro SMTP 6.0.6) with ESMTPS id 6435586 for lml@lancaironline.net; Wed, 21 Aug 2013 08:09:32 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.12.143.80; envelope-from=vtailjeff@aol.com Received: from mtaout-db05.r1000.mx.aol.com (mtaout-db05.r1000.mx.aol.com [172.29.51.197]) by omr-m06.mx.aol.com (Outbound Mail Relay) with ESMTP id 2BDF670000095 for ; Wed, 21 Aug 2013 08:08:58 -0400 (EDT) Received: from [10.150.104.173] (unknown [166.205.67.46]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by mtaout-db05.r1000.mx.aol.com (MUA/Third Party Client Interface) with ESMTPSA id E0839E0000C1; Wed, 21 Aug 2013 08:08:54 -0400 (EDT) References: In-Reply-To: Mime-Version: 1.0 (1.0) Content-Type: multipart/alternative; boundary=Apple-Mail-EF514418-372E-4946-8959-A3D55CF26B67 X-Original-Message-Id: <59ECAE34-535D-4102-8A49-810AEC2FE6BC@aol.com> Content-Transfer-Encoding: 7bit X-Mailer: iPad Mail (9B206) From: vtailjeff@aol.com Subject: Re: [LML] Re: Prop governor's X-Original-Date: Wed, 21 Aug 2013 06:53:33 -0500 X-Original-To: Lancair Mailing List x-aol-global-disposition: G x-aol-sid: 3039ac1d33c55214add61258 X-AOL-IP: 166.205.67.46 --Apple-Mail-EF514418-372E-4946-8959-A3D55CF26B67 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii Thank you Paul!=20 For the rest...refer to your propeller owner's manual... Not Glenda the Good= Witch of the Wind. Jeff ;) Sent from my iPad On Aug 21, 2013, at 6:40 AM, Paul Miller wrote: > Maybe we should refer to the manuals on how props go to low pitch. It ain= 't relative wind or any other kind of wind. It is a "really big spring" in t= he hub. =46rom Hartzell: >> (2) Centrifugal twisting moment acting on the blades moves the blades to a= low blade angle (low pitch) to increase RPM. Since the centrifugal twisting= moment is only present when the propeller is rotating, a mechanical spring i= s installed within the propeller to assist movement of the blades to a lower= pitch position as RPM decays, and to reduce the propeller pitch to the low p= itch stop when the propeller is static. With the blades at low pitch, the lo= ad on the starter when starting the engine is reduced significantly.=20 >> (3) Oil pressure opposes the spring and centrifugal twisting moment to mo= ve the blades to a high blade angle (high pitch), reducing engine RPM.=20 >> (4) If oil pressure is lost at any time, the propeller will move to low p= itch. This occurs because the spring and blade centrifugal twisting moment a= re no longer opposed by hydraulic oil pressure. The propeller will then redu= ce blade pitch to the low pitch stop. > On 2013-08-20, at 1:45 PM, Jack Morgan wrote: >=20 >> If oil pressure fails, standard CS props are driven flat by the relative w= ind ... --Apple-Mail-EF514418-372E-4946-8959-A3D55CF26B67 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=utf-8

Thank you Paul!

For the rest...refer to your propeller owner's manual..= . Not Glenda the Good Witch of the Wind.

Jeff ;)
Sent from my iPad

On Aug 21, 2013, at 6:40 AM, Paul Mille= r <pjdmiller@gmail.com> wro= te:

Maybe we should r= efer to the manuals on how props go to low pitch. It ain't relative wi= nd or any other kind of wind. It is a "really big spring" in the hub. &= nbsp;=46rom Hartzell:
(2) Centrifugal twi= sting moment acting on the blades moves the blades to a low blade angle (low= pitch) to increase RPM. Since the centrifugal twisting moment is only prese= nt when the propeller is rotating, a mechanical spring is installed within t= he propeller to assist movement of the blades to a lower pitch position as R= PM decays, and to reduce the propeller pitch to the low pitch stop when the p= ropeller is static. With the blades at low pitch, the load on the starter wh= en starting the engine is reduced significantly.
(3) Oil pressure opposes the spring and centrifugal twisting moment to= move the blades to a high blade angle (high pitch), reducing engine RPM.&nb= sp;
(4) If oil pressure is lost at any time, the p= ropeller will move to low pitch. This occurs because the spring and blade ce= ntrifugal twisting moment are no longer opposed by hydraulic oil pressure. T= he propeller will then reduce blade pitch to the low pitch stop.
<= /blockquote>
On 2013-08-20, at 1:45 PM, Jack Morgan <jmorgan1023@comcast.net> wrote= :

If oil pressure fails, standard CS props are d= riven flat by the relative wind ...

= --Apple-Mail-EF514418-372E-4946-8959-A3D55CF26B67--