Return-Path: <13brv3@bellsouth.net> Received: from imf19aec.mail.bellsouth.net ([205.152.59.67] verified) by logan.com (CommuniGate Pro SMTP 4.1.8) with ESMTP id 2777710 for flyrotary@lancaironline.net; Sat, 29 Nov 2003 20:55:42 -0500 Received: from rad ([68.212.0.112]) by imf19aec.mail.bellsouth.net (InterMail vM.5.01.06.05 201-253-122-130-105-20030824) with ESMTP id <20031130015538.JDMA1942.imf19aec.mail.bellsouth.net@rad> for ; Sat, 29 Nov 2003 20:55:38 -0500 From: "Russell Duffy" <13brv3@bellsouth.net> To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Re: Brief flight report Date: Sat, 29 Nov 2003 19:55:38 -0600 Message-ID: <000001c3b6e5$0db61a70$6001a8c0@rad> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0001_01C3B6B2.C31BAA70" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.4510 Importance: Normal In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 This is a multi-part message in MIME format. ------=_NextPart_000_0001_01C3B6B2.C31BAA70 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable What maximum power are you willing to run continuously? 7-8 gph =20 =20 Do you want to optimize the prop for cruise, or climb? Cruise=20 =20 =20 If this were a Lycoming, and we were trying to find the best cruise = speed, we'd go to 8000 ft, and apply full throttle. Since we know that's about = 75% power for a NA engine, the goal would be to pitch the prop for the = redline RPM at that altitude. Simple. =20 Unfortunately, we don't have book numbers to look up, and we can't even = go by the 75% rule, since we aren't all making the same 100% power. For example, Tracy is making 190+, but others are below 150, so 75% power = for Tracy, may be more than someone else can make at 100%. I'm willing to = run my engine at 150 HP continuous, which makes it the equivalent of a 200 = HP Lycoming in cruise. I can't say what that is in gph though. =20 =20 Like everyone has said, it's a balance between climb and cruise, and = since we can't look up numbers in a book, we have to figure this out experimentally. Now that you've defined your limits, you can experiment with pitch until you can satisfy your needs. Or you can just buy the in-flight adjustable option and save us all a bunch of typing :-) =20 Have fun, Rusty (flying tomorrow for sure) =20 =20 =20 =20 =20 ------=_NextPart_000_0001_01C3B6B2.C31BAA70 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Message
 What maximum power are you = willing to=20 run continuously?  = 7-8 gph  
 
 Do you want to optimize the prop = for=20 cruise, or climb? Cruise 
 
 
If this were a = Lycoming, and=20 we were trying to find the best cruise speed, we'd go to 8000 ft, = and apply=20 full throttle.  Since we know that's about 75% power for a NA = engine,=20 the goal would be to pitch the prop for the redline RPM at that=20 altitude.  Simple.
 
Unfortunately, we don't = have book=20 numbers to look up, and we can't even go by the 75% rule, since we = aren't all=20 making the same 100% power.  For example, Tracy is making 190+, but = others=20 are below 150, so 75% power for Tracy, may be more than someone else can = make at=20 100%.  I'm willing to run my engine at 150 HP continuous, = which makes=20 it the equivalent of a 200 HP Lycoming in cruise.  I can't say what = that is=20 in gph though.  
 
Like everyone has said, = it's a=20 balance between climb and cruise, and since we can't look up numbers in = a book,=20 we have to figure this out experimentally.  Now that you've = defined=20 your limits, you can experiment with pitch until you can satisfy = your=20 needs.  Or you can just buy the in-flight adjustable option = and save=20 us all a bunch of typing :-)
 
Have=20 fun,
Rusty (flying tomorrow = for=20 sure)     

 

 

 

 

------=_NextPart_000_0001_01C3B6B2.C31BAA70--