X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Mon, 21 Apr 2014 11:43:52 -0400 Message-ID: X-Original-Return-Path: Received: from ndjsnpf01.ndc.nasa.gov ([198.117.1.121] verified) by logan.com (CommuniGate Pro SMTP 6.0.9e) with ESMTP id 6833176 for lml@lancaironline.net; Fri, 18 Apr 2014 11:58:44 -0400 Received-SPF: pass receiver=logan.com; client-ip=198.117.1.121; envelope-from=valin.b.thorn@nasa.gov Received: from ndmsppt102.ndc.nasa.gov (ndmsppt102.ndc.nasa.gov [198.117.0.67]) by ndjsnpf01.ndc.nasa.gov (Postfix) with ESMTP id B9291D0454 for ; Fri, 18 Apr 2014 10:54:57 -0500 (CDT) Received: from NDMSCHT113.ndc.nasa.gov (ndmscht113-pub.ndc.nasa.gov [198.117.0.213]) by ndmsppt102.ndc.nasa.gov (8.14.5/8.14.5) with ESMTP id s3IFvjKS024287 for ; Fri, 18 Apr 2014 10:57:45 -0500 Received: from NDMSMBX402.ndc.nasa.gov ([169.254.2.252]) by NDMSCHT113.ndc.nasa.gov ([198.117.0.213]) with mapi id 14.03.0174.001; Fri, 18 Apr 2014 10:57:45 -0500 From: "Thorn, Valin B. (JSC-VA411)" X-Original-To: Lancair Mailing List X-Original-CC: "Thorn, Valin B. (JSC-VA411)" Subject: Re: Hartzell Prop Governor Low RPM Capability Thread-Topic: Hartzell Prop Governor Low RPM Capability Thread-Index: Ac9bHuA4BN9ynFnPRwOKQgZpTvRqqw== X-Original-Date: Fri, 18 Apr 2014 15:57:44 +0000 X-Original-Message-ID: <0705A91F9164914998F23A2F0BB661A912C2EB@NDMSMBX402.ndc.nasa.gov> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [66.35.45.94] Content-Type: multipart/alternative; boundary="_000_0705A91F9164914998F23A2F0BB661A912C2EBNDMSMBX402ndcnasa_" MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.11.96,1.0.14,0.0.0000 definitions=2014-04-18_01:2014-04-18,2014-04-18,1970-01-01 signatures=0 --_000_0705A91F9164914998F23A2F0BB661A912C2EBNDMSMBX402ndcnasa_ Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable For Legacy flyers, what rate of descent do you see in engine out scenarios,= at best glide speed (120 KIAS), in a clean configuration, with your prop p= ulled all the way back for minimum drag? Particularly curious for those with feathering props, what descent rate do = you have in this configuration with your prop feathered? Thanks, Valin Thorn From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of Vali= n & Allyson Thorn Sent: Monday, March 24, 2014 8:06 PM To: lml@lancaironline.net Subject: [LML] Hartzell Prop Governor Low RPM Capability I was surprised to learn recently that the Hartzell propeller governor (S S= eries) cannot adjust the blade pitch with an engine speed below about 1800 = rpm. Seems like that could be a problem in an engine out glide scenario, w= here the prop stays at flat pitch, high drag. I talked to a guy at Hartzell Technical Support and he confirmed that's how= their S series governors work. He said it's not a problem and that they a= re on all the Cirrus airplanes. But, with the Cirrus' single lever control= linkage, I don't think Cirrus pilots can adjust the blade pitch in an engi= ne out scenario anyway. For the Legacy flyers out there flying with the Hartzell governor, when you= 're at best glide speed of 120 KIAS, are you able to get enough engine rpm = to get maximum blade pitch (low drag) or not...? Thanks, Valin Thorn Legacy Project Boulder, Colorado USA --_000_0705A91F9164914998F23A2F0BB661A912C2EBNDMSMBX402ndcnasa_ Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

For Legacy flyers,= what rate of descent do you see in engine out scenarios, at best glide spe= ed (120 KIAS), in a clean configuration, with your prop pulled all the way back for minimum drag? 

 <= /span>

Particularly curio= us for those with feathering props, what descent rate do you have in this c= onfiguration with your prop feathered?

 <= /span>

Thanks,=

 <= /span>

Valin Thorn

 <= /span>

 <= /span>

 <= /span>

From: Lancair = Mailing List [mailto:lml@lancaironline.net] On Behalf Of Valin & Allyson Thorn
Sent: Monday, March 24, 2014 8:06 PM
To: lml@lancaironline.net
Subject: [LML] Hartzell Prop Governor Low RPM Capability<= /span>

 

I was surprised to= learn recently that the Hartzell propeller governor (S Series) cannot adju= st the blade pitch with an engine speed below about 1800 rpm.  Seems like that could be a problem in an engine out glide scena= rio, where the prop stays at flat pitch, high drag.

 <= /span>

I talked to a guy = at Hartzell Technical Support and he confirmed that’s how their S ser= ies governors work.  He said it’s not a problem and that they are on all the Cirrus airplanes.  But, with the Cirrus’ single = lever control linkage, I don’t think Cirrus pilots can adjust the bla= de pitch in an engine out scenario anyway.

 <= /span>

For the Legacy fly= ers out there flying with the Hartzell governor, when you’re at best = glide speed of 120 KIAS, are you able to get enough engine rpm to get maximum blade pitch (low drag) or not…?

 <= /span>

Thanks,=

 <= /span>

Valin Thorn

Legacy Project

Boulder, Colorado = USA

 <= /span>

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