X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from fed1rmmtao103.cox.net ([68.230.241.43] verified) by logan.com (CommuniGate Pro SMTP 5.2.13) with ESMTP id 3576516 for flyrotary@lancaironline.net; Fri, 10 Apr 2009 11:04:50 -0400 Received-SPF: none receiver=logan.com; client-ip=68.230.241.43; envelope-from=alventures@cox.net Received: from fed1rmimpo03.cox.net ([70.169.32.75]) by fed1rmmtao103.cox.net (InterMail vM.7.08.02.01 201-2186-121-102-20070209) with ESMTP id <20090410150321.SOWB4363.fed1rmmtao103.cox.net@fed1rmimpo03.cox.net> for ; Fri, 10 Apr 2009 11:03:21 -0400 Received: from BigAl ([72.192.135.181]) by fed1rmimpo03.cox.net with bizsmtp id dr3M1b0083uzsQg04r3Mek; Fri, 10 Apr 2009 11:03:21 -0400 X-Authority-Analysis: v=1.0 c=1 a=g9my-20mbB0A:10 a=Bj78yBxbUTUA:10 a=Ia-xEzejAAAA:8 a=LHAjlbFdwWuxfutzWgEA:9 a=GyKd-CLMgjUMNFhzVy4A:7 a=zFP012BSIEnodX23EAcHKgGsv_YA:4 a=sNEyDEdYjLsA:10 a=EzXvWhQp4_cA:10 a=Lw8yylRUm9eCI49W:21 a=uMGW7BTxndtyHnox:21 a=Pqy5teFHlx4-l6z2LdUA:9 a=J74SkTp0e3IMZ6v-9ycA:7 a=hvx9DeKPzc1mV1znbg8lZ-_dFdYA:4 a=37WNUvjkh6kA:10 X-CM-Score: 0.00 From: "Al Gietzen" To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Re: [Lancair_ES] Re: Rotary Engines Date: Fri, 10 Apr 2009 08:03:46 -0800 Message-ID: <0B477D263A414407B7A90416579A05CD@BigAl> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0008_01C9B9B2.DFCD70F0" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.6838 Importance: Normal X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 Thread-Index: Acm54AS7/aqQ/Gp6Qgi6bMmDg/ZQiwAFCskg In-Reply-To: This is a multi-part message in MIME format. ------=_NextPart_000_0008_01C9B9B2.DFCD70F0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Good response, Mark. =20 Aside from whatever the details are; I was up at 14,500' the other day, cruising along at 182 KTAS, in my comfortable 4-place airplane, burning about 10 gph of $2.17/ga fuel; and doing it very smo-o-o-othly. It's = the results that count. =20 Al (Velocity 20B) =20 -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Mark Steitle Sent: Friday, April 10, 2009 5:26 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: [Lancair_ES] Re: Rotary Engines =20 Gary,=20 =20 Thanks for adding a more technical tone to this discussion. Yes, I was = not accounting for all the misc pieces needed to make the rotary run, but = then I wasn't considering all the little pieces needed to make a conventional piston engine run either. Of the pieces that normally fail and end up poking out through the engine case, I think you'll agree that the rotary = has significantly fewer of those. In fact, I have never seen a rotary with = a thrown connecting rod. ;-) =20 Having a liquid cooling system is a two-edged sword, but its not = anything that can't be overcome with good engineering. For coolant lines on my installation I used aluminum tubing connected to the engine and radiator = via "Wiggins" couplings. I monitor coolant pressure, coolant level, and = coolant temperature. Of course, if I catch a Canadian goose in the radiator, it will likely loose its ability to cool the engine, but then you have the = same risk with an air-cooled engine. =20 As for the bsfc, do your numbers reflect the modern EFI systems, or carbureted engines. Tracy Crook realized a significant improvement in = bsfc when he switched from carburetors to EFI. The new "Renesis" rotary = engine has a better bsfc due to the side exhaust ports. Anyway, I prefer to consider it in "dollars per air-mile". By the time you factor in the = cost savings for purchasing and maintaining a rotary engine over a certified engine, and that the rotary runs happily (prefers) on 89 UL fuel (half = the cost of avgas), the cost per mile tips significantly in favor of the = rotary. (Reading the recent post about the $2300.00 oil pan practically brought tears to my eyes.) I guess its the German in me that caused me to seek = out something better, or different. =20 =20 Ahhhh... you mentioned the magic word, "turbo-charger". I built my = engine with the intention of turbo-charging as it was initially turbo-charged = in its former life. After much thought, I decided to follow the KISS = principle and go N/A. But there's a little voice in my head that keeps whispering "turbo-charge". With the rotary's high energy exhaust gasses, turbo's = are a natural solution. Yes they add weight, but not much more than my = current exhaust system. Stay tuned... =20 One thing that I hadn't mentioned that could be considered a negative = for the rotary engine is that very few A&P's know anything about rotary = engines. Heck, very few auto mechanics know how to work on a rotary engine. But, = if I'm there with my repairman's certificate in hand, who needs an A&P? = Also, rotary parts are less plentiful if you get stuck in some = hole-in-the-wall town. But there is always UPS overnight. =20 =20 Gary, thanks again for your thoughtful post. I'm not trying to convert anyone to a rotary engine, I only want to see it get a fair shake. =20 =20 Mark S. =20 P.S. I've CC'd the Fly Rotary group as they need something to talk = about (the list has been rather quiet lately). =20 =20 ------=_NextPart_000_0008_01C9B9B2.DFCD70F0 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Good response, = Mark.

 

Aside from whatever the details = are; I was up at 14,500’ the other day, cruising along at 182 KTAS, in my comfortable 4-place airplane, burning about 10 gph of $2.17/ga fuel; and = doing it very smo-o-o-othly.  It’s the results that = count.

 

Al (Velocity = 20B)

 

-----Original = Message-----
From: Rotary motors in = aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Mark Steitle
Sent: Friday, April 10, = 2009 5:26 AM
To: Rotary motors in = aircraft
Subject: [FlyRotary] Re: [Lancair_ES] Re: Rotary Engines

 

Gary,

 

Thanks for adding a more technical tone to = this discussion.  Yes, I was not accounting for all the misc pieces = needed to make the rotary run, but then I wasn't considering all the little pieces = needed to make a conventional piston engine run either.  Of the pieces = that normally fail and end up poking out through the engine case, I think = you'll agree that the rotary has significantly fewer of those.  In fact, I = have never seen a rotary with a thrown connecting rod.  = ;-)

 

Having a liquid cooling system is a two-edged = sword, but its not anything that can't be overcome with good = engineering.  For coolant lines on my installation I used aluminum tubing connected to = the engine and radiator via "Wiggins" couplings.  I monitor coolant pressure, coolant level, and coolant temperature. =  Of course, if I catch a Canadian goose in the radiator, it will likely = loose its ability to cool the engine, but then you have the same risk with an = air-cooled engine. 

As for the bsfc, do your numbers = reflect the modern EFI systems, or carbureted engines.  Tracy Crook = realized a significant improvement in bsfc when he switched from carburetors to EFI.  The new "Renesis" rotary engine has a = better bsfc due to the side exhaust ports.  Anyway, I prefer to consider it in "dollars per air-mile".  By the = time you factor in the cost savings for purchasing and maintaining a = rotary engine over a certified engine, and that the rotary runs happily = (prefers) on 89 UL fuel (half the cost of avgas), the cost per mile tips significantly in favor of the rotary.  (Reading the = recent post about the $2300.00 oil pan practically brought tears to my eyes.)  = I guess its the German in me that caused me to seek out something = better, or different. 

 

Ahhhh... you mentioned the magic word, "turbo-charger".  I built my engine with the = intention of turbo-charging as it was initially turbo-charged in its = former life.  After much thought, I decided to follow the = KISS principle and go N/A.  But there's a little voice in my head that keeps = whispering "turbo-charge".  With the rotary's high energy exhaust = gasses, turbo's are a natural solution.  Yes they add weight, but not = much more than my current exhaust system.  Stay = tuned...

 

One thing that I hadn't mentioned that could = be considered a negative for the rotary engine is that very few A&P's = know anything about rotary engines.  Heck, very few auto mechanics know = how to work on a rotary engine.  But, if I'm there with my repairman's certificate in hand, who needs an A&P?  Also, rotary parts are = less plentiful if you get stuck in some hole-in-the-wall town.  But = there is always UPS overnight. 

 

Gary, thanks again for your thoughtful = post.  I'm not trying to convert anyone to a rotary engine, I only = want to see it get a fair shake.  

 

Mark S.

 

P.S.  I've CC'd the Fly Rotary group as = they need something to talk about (the list has been rather quiet = lately).

 

 

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