X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Fri, 25 Jun 2010 20:04:26 -0400 Message-ID: X-Original-Return-Path: Received: from mail-vw0-f52.google.com ([209.85.212.52] verified) by logan.com (CommuniGate Pro SMTP 5.3.8) with ESMTP id 4371072 for lml@lancaironline.net; Fri, 25 Jun 2010 18:36:32 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.212.52; envelope-from=mehapgood@gmail.com Received: by vws3 with SMTP id 3so71284vws.25 for ; Fri, 25 Jun 2010 15:35:57 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:message-id:from:to:in-reply-to:content-type :content-transfer-encoding:x-mailer:mime-version:subject:date :references; b=i+wv1FcSj3z3j3ZBsA3eb8AV0r5nnNXVoKunI94MlpIuQoB5bQ2QyttLyYmU4scqPE mNrHxzoBAWLK7pEICUAmOJRoeJKA70/09Y6XVgKSy8uf8eAVNxt+YNcHn66W0VgfMGYr QrNjs8KV7rQm2RkIHx5TzcReVdegg86jtOLfo= Received: by 10.229.181.13 with SMTP id bw13mr938782qcb.38.1277505357482; Fri, 25 Jun 2010 15:35:57 -0700 (PDT) X-Original-Return-Path: Received: from [192.168.1.15] (ool-45781c73.dyn.optonline.net [69.120.28.115]) by mx.google.com with ESMTPS id v20sm18189125qce.34.2010.06.25.15.35.55 (version=TLSv1/SSLv3 cipher=RC4-MD5); Fri, 25 Jun 2010 15:35:56 -0700 (PDT) X-Original-Sender: Matt Hapgood X-Original-Message-Id: From: Matt Hapgood X-Original-To: Lancair Mailing List In-Reply-To: Content-Type: multipart/alternative; boundary=Apple-Mail-53-697899765 Content-Transfer-Encoding: 7bit X-Mailer: iPad Mail (7B367) Mime-Version: 1.0 (iPad Mail 7B367) Subject: Re: [LML] Re: LNC2/320 Cruise Speed X-Original-Date: Fri, 25 Jun 2010 18:35:26 -0400 References: --Apple-Mail-53-697899765 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable My experience is that I LOSE MP with increased RPM (all other things = held equal).=20 Matt On Jun 25, 2010, at 6:29 PM, Sky2high@aol.com wrote: > Matt, > =20 > If Lorn is using ram air, the increase in IAS from 139 to 152 would = increase the ram pressure (theoretical is about .22" Hg for that speed = change) and the prop going by more often might also be a slight boost to = inlet ram pressure. He didn't mention any throttle change. His AOA = would have decreased a bit too. > =20 > Grayhawk > =20 > In a message dated 6/25/2010 3:49:00 P.M. Central Daylight Time, = matt.hapgood@alumni.duke.edu writes: > Why did MP change with fuel/RPM change? >=20 > Matt >=20 > On Jun 25, 2010, at 1:59 PM, Lorn H Olsen wrote: >=20 > > 06/22/10 I was flying from Detroit to Ft Lauderdale at 11,000. With = nothing else to do, I thought that I would take a few measurements. > >=20 > > Condition LOP Lo ROP Hi > > --------- -------- --------- > > 11,000 IA 2,350RPM 2,700 RPM > > 13,000 DA 19.3"MP 19.8"MP > > 30.08 "Hg 6.0 GPH 8.6 GPH > > 12=C2=B0C temp 139 kts IAS 152 kts IAS > > 35=C2=B0F dewpt? 168 kts TAS 183 kts TAS > > 1,670 lbs > >=20 > > For a 43% increase in fuel, a 9% increase in airspeed doesn't sound = like much. However, 183 kts airspeed at 13,000 ft density altitude, no = matter how you do it, is great. > >=20 > > The LOP reading at .435 BSFC comes out to HP =3D 36 * 6 * .435 =3D = 94.0 HP or 94.0 / 160 =3D 59% power. > >=20 > > Comments appreciated. > >=20 > > Lorn > >=20 > > -- > > Lorn H. 'Feathers' Olsen, MAA, ASMEL, ASES, Comm, Inst > > DynaComm, Corp., 248-345-0500, mailto:lorn@dynacomm.us > > LNC2, FB90/92, O-320-D1F, 1,700 hrs, N31161, Y47, SE Michigan > >=20 > >=20 > > -- > > For archives and unsub = http://mail.lancaironline.net:81/lists/lml/List.html >=20 > -- > For archives and unsub = http://mail.lancaironline.net:81/lists/lml/List.html --Apple-Mail-53-697899765 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable
My experience is that I LOSE MP = with increased RPM (all other things held = equal). 

Matt

On Jun 25, 2010, at 6:29 PM, Sky2high@aol.com = wrote:

Matt,
 
If Lorn is using ram air, the increase in IAS from 139 to 152 would=20= increase the ram pressure (theoretical is about .22" Hg for that speed=20= change) and the prop going by more often might also be a = slight=20 boost to inlet ram pressure.  He didn't mention any throttle=20= change.  His AOA would have decreased a bit too.
 
Grayhawk
 
In a message dated 6/25/2010 3:49:00 P.M. Central Daylight Time,=20 matt.hapgood@alumni.duke.edu<= /a> writes:
Why did=20 MP change with fuel/RPM change?

Matt

On Jun 25, 2010, at = 1:59=20 PM, Lorn H Olsen <lorn@dynacomm.us> = wrote:

> 06/22/10 I was=20 flying from Detroit to Ft Lauderdale at 11,000. With nothing else to = do, I=20 thought that I would take a few measurements.
> =
>  =20 Condition   LOP Lo      ROP = Hi
>  =20 ---------   --------    = ---------
>  =20 11,000 IA   2,350RPM    2,700 = RPM
>  =20 13,000 DA   19.3"MP     = 19.8"MP
>  =20 30.08 "Hg   6.0 GPH     8.6 = GPH
>  =20 12=C2=B0C temp   139 kts IAS 152 kts IAS
>   = 35=C2=B0F dewpt?=20 168 kts TAS 183 kts TAS
>   1,670 lbs
>
> = For a=20 43% increase in fuel, a 9% increase in airspeed doesn't sound like = much.=20 However, 183 kts airspeed at 13,000 ft density altitude, no matter how = you do=20 it, is great.
>
> The LOP reading at .435 BSFC comes out = to HP =3D=20 36 * 6 * .435 =3D 94.0 HP or 94.0 / 160 =3D 59% power.
> =
> Comments=20 appreciated.
>
> Lorn
>
> --
> Lorn H.=20= 'Feathers' Olsen, MAA, ASMEL, ASES, Comm, Inst
> DynaComm, = Corp.,=20 248-345-0500, mailto:lorn@dynacomm.us
> = LNC2, FB90/92, O-320-D1F, 1,700=20 hrs, N31161, Y47, SE Michigan
>
>
> --
> For=20= archives and unsub=20 http://mail.= lancaironline.net:81/lists/lml/List.html

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