X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from an-out-0708.google.com ([209.85.132.244] verified) by logan.com (CommuniGate Pro SMTP 5.2.12) with ESMTP id 3527332 for flyrotary@lancaironline.net; Wed, 04 Mar 2009 15:36:25 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.132.244; envelope-from=msteitle@gmail.com Received: by an-out-0708.google.com with SMTP id b38so2029645ana.7 for ; Wed, 04 Mar 2009 12:35:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:content-type; bh=GWtM2yzqWCQYTBx8aS1QiZH5WRz9RIxQNo1+e+jDupg=; b=iXydzDceAlD9M3Vt4ElGQrmpLGBFiLaivB+nwOCzIU+jjmlQlI73jclG2EJJKz3rmt OQmUsRRWdq8sDJFeIeDcF4yQQugBsBYbz+ikkMouS37fEAmo4NVOOEauM5VJGRNqZgGA NGiPatY9492A9uSr23T4p7Nt+qexDRiO2te04= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=qEG9N32p5vvPSOOF9Iz9+JGTHv2CilmFUu7+uWJcev75L5CqMO6zJRDUkyfjznOyAS hR/K3yyI99UDR96aQOjseue+jaIqh72NHsKMhGWF7a2LOEmUWkwXulqGVQntbc6Tbkkq Z7KxwG5xoLpexN09TBvOemj5h40+FailoKMxk= MIME-Version: 1.0 Received: by 10.100.154.9 with SMTP id b9mr291134ane.64.1236198949789; Wed, 04 Mar 2009 12:35:49 -0800 (PST) In-Reply-To: References: Date: Wed, 4 Mar 2009 14:35:49 -0600 Message-ID: <5cf132c0903041235h432f585bwe96b697f7b717ef1@mail.gmail.com> Subject: Re: [FlyRotary] Re: Questions on buying a rotary plane From: Mark Steitle To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=0016e644c5e2462297046450ff23 --0016e644c5e2462297046450ff23 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable Yes, I have an alcohol tester and I'm not afraid to use it. So far, I haven't detected any alcohol in any of the fuel I have purchased locally. So, Y'all come to Lockhart, TX and fill 'er up with mogas. ;-) I have a 5= 0 gallon fuel trailer with a heavy duty 12v electric pump and Vallero is just 1 mile up the road. Not a big deal. Mark On Wed, Mar 4, 2009 at 1:33 PM, William Wilson wrote= : > More car gas is polluted with alcohol nowadays because the distributors > don't always want to maintain separate facilities for everything, even wh= ere > alcohol is not required in fuel, it can be easier for them to just sell i= t > anyway. Of course if you have an airport selling mogas it won't have > alcohol but if you self fuel from the local gas station you may find ther= e > is alcohol even if your state doesn't mandate it. Would be good to doubl= e > check. > > Since the rotary runs perfectly fine in cars with alcohol, so long as you= r > fuel tanks and plumbing can handle it without falling apart, you shouldn'= t > have a problem. Alcohol may have a bit less power but not enough to be > unsafe. Important thing for combustion properties is the octane of the f= uel > which alcohol does not reduce. > > Rumors of alcohol causing frozen fuel are just FUD. No one has ever seen > it happen and the chemistry does not make it particularly likely. Ethano= l > freezes at -114C! > > On Wed, Mar 4, 2009 at 5:21 AM, Mark Steitle wrote: > >> Mike, >> >> I agree with you that some of the Lycomings can burn mogas, but few >> actually do it. I belong to the Lancair list and they are constantly >> debating how to (or not to) run their engines so as to not damage them. >> Most are just plain scared to run their engines lean of peak where they = are >> able to get close to the "advertised" bsfc. They're willing to burn mor= e >> fuel in order to sleep better at night. But the rotary is designed to r= un >> on mogas. So, why not do it? Alcohol and possible vapor lock are the o= nly >> issues I know of, and with a properly designed EFI fuel system, vapor lo= ck >> isn't an issue. As long as they don't start blending alcohol in the fue= l in >> my neck of the woods, I'll keep burning mogas and pocketing the differen= ce. >> >> >> You stated, "But really the biggest motivation was to do something a >> little different." As for that statement... I couldn't agree more, but = how >> do you quantify something like that? And I believe that it isn't just >> different, but in a lot of ways the rotary is definitely better. >> Mark S. >> On Tue, Mar 3, 2009 at 9:55 PM, Mike Wills wrote: >> >>> Glad I woke you guys up! :-) >>> >>> While it may appear from my post that I was trying to discourage this g= uy >>> and am not happy with my rotary powered airplane that is not the case. = I'm >>> very happy with it. Will be even happier once I get all of the little >>> glitches fixed so I can just fly it. >>> >>> I simply wanted to make sure William understands what he's getting int= o. >>> What appears to be a fairly straight forward mod is a lot more complica= ted >>> than it appears and there are potential pitfalls that are not necessari= ly >>> obvious. >>> >>> My bad on the misread regarding fuel efficiency - he was talking >>> about homebuilt aircraft versus factory built planes, not rotaries vers= us >>> certified engines. I think he's still way off base here which was why >>> I replied to his post. >>> >>> Al, I dont know anyone who actually KNOWS what BSFC they acheive with >>> their Lyc/Cont. I know that low .40s is a published number that is stuc= k in >>> my head. I know what kind of fuel consumption I got with my Lyc powered >>> RV-6A at cruise and I know there are certainly enough flying Lyc powere= d RVs >>> to pretty firmly establish a cruise performance baseline. Since there a= re >>> more flying rotary powered RVs than other types, seems like we should b= e >>> able to get at least an idea of how they compare. Lets challenge the ro= tary >>> RV fliers here to post real cruise performance (altitude, TAS, fuel >>> consumption) and answer the question. Or give me a year and 100 hours a= nd >>> I'll let you know how my RV-4 stacks up against the -6A for a data poin= t. >>> >>> As for your performance against conventional powered Velocities, thats >>> great news. I think thats one of the significant short comings of our l= ittle >>> group here. Common perception is that rotaries are gas hogs and we dont= do >>> anything to accurately document and advertise our performance. >>> >>> Mark, I agree that burning Mogas definitely makes a big difference >>> economy-wise. But that's a red herring. You could legally burn Mogas in= a >>> Lyc/Cont also - just that most guys who are too conservative to choose = an >>> auto conversion are also too conservative to burn Mogas. Burning Mogas = isnt >>> the exclusive territory of the rotary. I personally know a guy with a 2= 00HP >>> Lyc in an RV-8 who has burned Mogas exclusively for years. Really what = it >>> comes down to is convenience and comfort. Lets be fair, compare apples = to >>> apples, and while we're at it throw in the additional cost and hassle o= f >>> having to pour in 2 stroke oil for your rotary (assuming you do that as= most >>> seem to do). >>> >>> I do totally agree with you on the price of parts. And that was one of >>> my huge motivations for going this route. But really the biggest motiva= tion >>> was to do something a little different. When my RV-4 finally makes it's >>> appearance at a fly-in (hopefully this year) it's not going to be lost = in >>> the sea of belly button RVs that show up. >>> >>> Mike Wills >>> RV-4 N144MW >>> >>> >>> >>> ----- Original Message ----- >>> *From:* Al Gietzen >>> *To:* Rotary motors in aircraft >>> *Sent:* Monday, March 02, 2009 9:51 PM >>> *Subject:* [FlyRotary] Re: Questions on buying a rotary plane >>> >>> I dont know where you got the idea that rotaries are more fuel >>> efficient. Lycosaurs/Continentals typically have BSFCs in the low .40s.= The >>> commonly accepted number for a rotary is about .50. Some here seem to d= o >>> better, others worse. >>> >>> >>> >>> Mike; >>> >>> >>> >>> I=92m not disagreeing with the points in your message; but I am wonderi= ng >>> if you know anybody actually flying a Lyc/Cont and achieving BSFC in th= e low >>> 40=92s. I see numbers like .43 or .45 bandied about, but I guess no on= e leans >>> enough when flying to get that for fear of burning out a valve =96 or w= orse. >>> I=92ve yet to hear from anyone flying a Velocity like mine with a Lyc w= ho >>> can surpass the speed/fuel burn that I get with the 20B. I don=92t know= why =96 >>> it surprised me; but there it is. >>> >>> >>> >>> I think in the real world operation the BSFCs are comparable. I may ha= ve >>> a bit lower drag because of smaller cowl; or other factors. >>> >>> >>> >>> Al >>> >>> >> > --0016e644c5e2462297046450ff23 Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: quoted-printable
Yes, I have an alcohol tester and I'm not afraid to use it.=A0 So = far, I haven't detected any alcohol in any of the fuel I have purchased= locally.=A0 So, Y'all come to Lockhart, TX and fill 'er=A0up with = mogas.=A0 ;-)=A0 I have a 50 gallon fuel trailer with a heavy duty 12v elec= tric pump=A0and Vallero is just 1 mile up the road.=A0 Not a big deal.
=A0
Mark

On Wed, Mar 4, 2009 at 1:33 PM, William Wilson <= span dir=3D"ltr"><fluffysheap@g= mail.com> wrote:
More car gas is polluted with al= cohol nowadays because the distributors don't always want to maintain s= eparate facilities for everything, even where alcohol is not required in fu= el, it can be easier for them to just sell it anyway.=A0 Of course if you h= ave an airport selling mogas it won't have alcohol but if you self fuel= from the local gas station you may find there is alcohol even if your stat= e doesn't mandate it.=A0 Would be good to double check.

Since the rotary runs perfectly fine in cars with alcohol, so long as y= our fuel tanks and plumbing can handle it without falling apart, you should= n't have a problem.=A0 Alcohol may have a bit less power but not enough= to be unsafe.=A0 Important thing for combustion properties is the octane o= f the fuel which alcohol does not reduce.

Rumors of alcohol causing frozen fuel are just FUD.=A0 No one has ever = seen it happen and the chemistry does not make it particularly likely.=A0 E= thanol freezes at -114C!

On Wed, Mar 4, 2009 at 5:21 AM, Mark Steitle <= msteitle@gmail.com> wrote:
Mike,
=A0
I agree with you that=A0some of the=A0Lycomings can=A0burn mogas,=A0bu= t=A0few actually do it.=A0 I belong to the Lancair list and they are consta= ntly debating how to (or not to) run their engines so as to not damage them= .=A0 Most are just plain scared to run their engines lean of peak where the= y are able to get close to the "advertised"=A0bsfc.=A0 They'r= e willing to burn more fuel in order to sleep better at night.=A0 But the r= otary is designed to run on mogas.=A0 So, why not do it?=A0 Alcohol=A0and p= ossible vapor lock=A0are the only issues I know of, and=A0with a properly d= esigned EFI fuel system, vapor lock isn't an issue.=A0=A0As long as the= y don't start blending alcohol in the fuel=A0in my neck of the woods, I= 'll keep=A0burning mogas and pocketing the difference.=A0
=A0
You stated, "But really the biggest motivation was to do somethin= g a little different."=A0 As for that statement... I couldn't agre= e more, but how do you quantify something like that?=A0 And I believe that = it isn't just different, but in a lot of ways=A0the rotary is definitel= y=A0better.=A0 =A0
Mark S.
On Tue, Mar 3, 2009 at 9:55 PM, Mike Wills <rv-4= mike@cox.net> wrote:
Glad I woke you guys up! :-)
=A0
While it may appear from my post that = I was trying to discourage this guy and am not happy with my rotary powered= airplane that is not the case. I'm very happy with it. Will be even ha= ppier once I get all of the little glitches fixed so=A0I can just fly it.
=A0
=A0I simply wanted to make sure Willia= m understands what he's getting into. What appears to be a fairly strai= ght forward mod is a lot more complicated than it appears and there are pot= ential pitfalls that are not necessarily obvious.
=A0
=A0My bad on the misread regarding fue= l efficiency - he=A0was talking about=A0homebuilt aircraft versus factory b= uilt planes, not rotaries versus certified engines. I=A0think he's stil= l way off base here which was why I=A0replied to his post.
=A0
=A0Al, I dont=A0know anyone who actual= ly KNOWS what BSFC they acheive with their Lyc/Cont. I know that low .40s i= s a published number that is stuck in my head.=A0I know what kind of fuel c= onsumption I got with my Lyc powered RV-6A at cruise=A0and I know there are= certainly enough flying Lyc powered RVs to pretty firmly establish a=A0cru= ise performance baseline. Since there are more flying rotary powered RVs th= an other types, seems like we should be able to get at least an idea of how= they compare.=A0Lets challenge the rotary RV fliers here to post real crui= se performance (altitude, TAS, fuel consumption) and answer the question. O= r give me a year and 100 hours and I'll let you know how my RV-4 stacks= up against the -6A for a data point.
=A0
=A0As for your performance against con= ventional powered Velocities, thats great news. I think thats one of the si= gnificant short comings of our little group here. Common perception is that= rotaries are gas hogs and we dont do anything to accurately document and a= dvertise our performance.
=A0
=A0Mark, I agree that burning Mogas de= finitely makes a big difference economy-wise. But that's a red herring.= You could legally burn Mogas in a Lyc/Cont also - just that most guys who = are too conservative to choose an auto conversion are also too conservative= to burn Mogas. Burning Mogas isnt the exclusive territory of the rotary.= =A0I personally know a guy with a 200HP Lyc in an RV-8 who has burned Mogas= exclusively for years. Really what it comes down to is convenience and com= fort.=A0Lets be fair,=A0compare apples to apples, and while we're at it= throw in the additional cost and hassle of having to pour in 2 stroke oil = for your rotary (assuming you do that as most seem to do).
=A0
=A0I do totally agree with you on the = price of parts. And that was one of my huge motivations for going this rout= e. But really the biggest motivation was to do something a little different= . When my RV-4 finally makes it's appearance at a fly-in (hopefully thi= s year) it's not going to be lost in the sea of belly button RVs that s= how up.
=A0
Mike Wills
RV-4 N144MW
=A0
=A0
----- Original Message -----
To: Rotary motors in aircraft
Sent: Monday, March 02, 2009 9:51 PM
Subject: [FlyRotary] Re: Questions on buying a rotary plane

=A0I dont know where you got the i= dea that rotaries are more fuel efficient. Lycosaurs/Continentals typically= have BSFCs in the low .40s. The commonly accepted number for a rotary is a= bout .50. Some here seem to do better, others worse.

=A0

Mike;

=A0

I=92m not disagreeing with the = points in your message; but I am wondering if you know anybody actually fly= ing a Lyc/Cont and achieving BSFC in the low 40=92s.=A0 I see numbers like = .43 or .45 bandied about, but I guess no one leans enough when flying to ge= t that for fear of burning out a valve =96 or worse.=A0 I=92ve yet to hear = from anyone flying a Velocity like mine = with a Lyc who can surpass the speed/fuel burn that I get with the 20B. I d= on=92t know why =96 it surprised me; but there it is.

=A0

I think in the real world opera= tion the BSFCs are comparable.=A0 I may have a bit lower drag because of sm= aller cowl; or other factors.

=A0

Al =A0

<= /div>



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