X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [24.25.9.101] (HELO ms-smtp-02-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 5.0.4) with ESMTP id 891364 for flyrotary@lancaironline.net; Wed, 21 Dec 2005 12:35:16 -0500 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.101; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-025-165.carolina.res.rr.com [24.74.25.165]) by ms-smtp-02-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id jBLHYT4p025334 for ; Wed, 21 Dec 2005 12:34:29 -0500 (EST) Message-ID: <001301c60654$cece1670$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Tracy, Ed, delta T Date: Wed, 21 Dec 2005 12:34:33 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0010_01C6062A.E5A6E130" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_0010_01C6062A.E5A6E130 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Tracy, to compare apples and apples, I would recommend the same IAS, = that way the dynamic pressure on the cores should be about the same at = both altitudes. Ed A ----- Original Message -----=20 From: Tracy Crook=20 To: Rotary motors in aircraft=20 Sent: Wednesday, December 21, 2005 10:33 AM Subject: [FlyRotary] Re: Tracy, Ed, delta T Good question Monty but I don't know. Only looked at it down low on = hot days. I'l try the following experiment next time I fly: Set fuel burn at a constant value (for roughly the same BTU rejection = in both cases). Measure delta T at 1000 ft then at 8000 ft. Airspeed = should also be similar. Do you think IAS or TAS should be the target? Tracy=20 ----- Original Message -----=20 From: Monty Roberts=20 To: Rotary motors in aircraft=20 Sent: Tuesday, December 20, 2005 8:36 PM Subject: [FlyRotary] Tracy, Ed, delta T Tracy and Ed, I was looking at an earlier post where Tracy listed air delta T = across his evap cores in cruise as 70-80F. How much increase in DeltaT = do you see with altitude? I would assume it would increase since the air = is both colder, and thinner. A 10 deg deltaT change makes a substantial = difference when sizing an intake. Monty ------=_NextPart_000_0010_01C6062A.E5A6E130 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Tracy, to compare apples and apples, I = would=20 recommend the same IAS, that way the dynamic pressure on the cores = should be=20 about the same at both altitudes.
 
Ed A
 
----- Original Message -----
From:=20 Tracy = Crook
Sent: Wednesday, December 21, = 2005 10:33=20 AM
Subject: [FlyRotary] Re: Tracy, = Ed, delta=20 T

Good question Monty but I don't know.  Only looked at it = down low on=20 hot days.  I'l try the following experiment next time I = fly:
 
Set fuel burn at a constant value (for roughly the same BTU = rejection in=20 both cases).  Measure delta T at 1000 ft then at 8000 ft.  = Airspeed=20 should also be similar.  Do you think IAS or TAS should be the=20 target?
 
Tracy
----- Original Message -----
From: Monty=20 Roberts
To: Rotary motors in = aircraft=20
Sent: Tuesday, December 20, = 2005 8:36=20 PM
Subject: [FlyRotary] Tracy, = Ed, delta=20 T

Tracy and Ed,
 
I was looking at an earlier post = where Tracy=20 listed air delta T across his evap cores in cruise as 70-80F. How = much=20 increase in DeltaT do you see with altitude? I would assume it would = increase since the air is both colder, and thinner. A 10 deg deltaT = change=20 makes a substantial difference when sizing an intake.
 
Monty
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