X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-ey0-f180.google.com ([209.85.215.180] verified) by logan.com (CommuniGate Pro SMTP 5.3.10) with ESMTP id 4573163 for flyrotary@lancaironline.net; Tue, 09 Nov 2010 22:49:16 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.215.180; envelope-from=dmlobner@gmail.com Received: by eyx24 with SMTP id 24so97746eyx.25 for ; Tue, 09 Nov 2010 19:48:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:in-reply-to :references:date:message-id:subject:from:to:content-type; bh=I/nJfavraNNHWwrRfP29muJ6+vPvgjs7mUAfjp14rBE=; b=ie7BQqMo2DD90nfDL2YIO/6AcQNDJsuhMXA/BBMQO/uvJm1COsJvz8VvxppfMnhD+O SGLGJCIV85ndg8zMVZHFACADIKjwj/h1NJ9+XfEsuMDERL5qQwBftFImMzbGizfAw0iK njRpEs75b7/c3+GYhIj1uvORPejbHPpBrFTFI= 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=Yd702SC1YimXKOTw33EPlNuyHswnvIW0eUyd6Pju36DM0+gQFE3YMv7Y8s2RwXZnJT QB0snUVaP/ZIfBsliAGl4yVPIVggN2/6bgGeo8xYZkbe0IWGS0xLQNSbVpaQpm4V6+92 biMnS1j9qOEO2bsibY/N2FMLC5VUal71AOlhk= MIME-Version: 1.0 Received: by 10.213.4.12 with SMTP id 12mr72200ebp.39.1289360919495; Tue, 09 Nov 2010 19:48:39 -0800 (PST) Received: by 10.213.12.205 with HTTP; Tue, 9 Nov 2010 19:48:39 -0800 (PST) In-Reply-To: References: Date: Tue, 9 Nov 2010 21:48:39 -0600 Message-ID: Subject: Re: [FlyRotary] Re: Current "state of the art" in rotaries - potential Bearhawk install From: Dustin Lobner To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=001517478bf09805950494aabb09 --001517478bf09805950494aabb09 Content-Type: text/plain; charset=ISO-8859-1 Dwayne, Thanks for the reply (and everyone else out there!) I do eventually plan on putting it on floats. Not initially, but that is the eventual plan. I read Tracy's comments on the redrive...from a gutcheck, I prefer what Performance did by tightening tolerances instead of loosening them, but a) I'm not an ME, so what do I know? and 2) if Tracy's works, that's proof right there, isn't it? Not to mentio the cost difference. Fuel system-wise I have a pretty good system in my head right now (I think), I'll get it onto paper soon. I'm on the Bearhawk Yahoo group, haven't been on lately though. I'll certainly try and make it to the cookout, please shoot me an email if you think about it when it comes around. TIG weld? Everything! (steel and aluminum alike). I'm a metallurgist, I prefer TIG for a variety of reasons (cleanliness, controllability, repeatability, can do it on aluminum). Not to mention, I have fairly extensive experience with TIG (GTAW nowadays) one steel and aluminum (and stainless) and zero with flame...it's a comfort factor thing. Dustin On Mon, Nov 8, 2010 at 12:51 PM, Dwayne Parkinson wrote: > Dustin, > > I don't know your goals or motivation for 300 hp, but there are usually two > reasons for lots of HP in a Bearhawk, floats and/or speed. > > Using some rather loose math here's how I think the Bearhawk works. The > cruise speeds posted by Pat Fagan and others using the O-540 are based on a > 250 HP O-540. They're flying at 65% so using simple math that's 162 HP in > cruise to get 165 MPH or almost 1 to 1 ratio of HP to MPH. A 180 HP engine > running at 65% is producing around 117 HP and is getting around 135 MPH or > about a 1.15 ratio. I don't recall the exact numbers but someone also > posted cruise speeds at 75% and 85% as well. When charting everything > together, what's interesting is that as you increase HP beyond 162 there is > a rapid decrease in the MPH returned per HP, mostly due to the draggy nature > of the airplane. My observation here is that reducing drag will yield a > bigger pay back than increasing HP once we get beyond 162 HP. > Now let's look at a rotary and see how it changes the game. First, you'll > need either a three rotor, a turbo two rotor or (hopefully) the new 16X to > get a reasonable and reliable 162 HP in cruise. Now assuming you put some > wheel pants on the plane, the game changer in terms of drag is the cooling > drag. The rotary allows some design flexibility to reduce that. Compare > the slippery nose of a Cirrus or a Corvalis to the nose of traditional > Bearhawk designs including the big square oil cooler hanging down. There > are some serious gains to be made there. So assuming you take advantage of > that, the same 162 HP produced by a rotary and an O-540 will result in a > higher cruise speed for the rotary. > > Now if we look at floats, it's a similar and much simpler story. We want > to add as much HP per weight as possible. The three rotor solution comes in > at about the same weight and slightly higher HP than an O-540. BTW - I > think the weight limit is 500 lbs on a Bearhawk for the engine. If you're > open to rotary engines then the three rotor is the winner because of the > higher HP. > > Now on to your questions: > > 1a) Bruce Turrentine comes highly rated as a builder but I haven't worked > with him. http://www.rotaryaviation.com/custom_mazda_engines.html > 1b) The all aluminum concept sure sounds appealing but what are we trying > to achieve? Is it more power for less weight? Consider that in all > likelihood, Mazda will release their 16X before you're ready for an > engine. http://www.mazda.com/mazdaspirit/rotary/16x/ One less rotor, > less oil consumption, aluminum side housings, better fuel consumption and > most importantly it theoretically delivers that O-540 level of 162 HP in > cruise yet it weighs in at less than an IO-360. > 2) I'd be careful regarding redrives and get as much info as possible. I'm > no expert but I found Tracy's "design philosophy" part 1, 2 and 3 very > interesting info. http://www.rotaryaviation.com/psru_development.htm You've > probably already read it, but at the very least, other manufacturers ought > to speak to the same points of concern before their parts get the privilege > of becoming a critical component of your airplane. > 3) Regarding reliability, my concern would be focused less on the engine > and more on the fact that experimental airplane crashes are most often > caused by fuel system and cooling failures. Fuel system and cooling are > common topics of discussion here for a reason. Draw your own conclusions, > but if you're going with an experimental engine I'd be very very diligent with > these two areas. > > Finally two other things: > > 1) As a fellow Bearhawk builder, I'd like to officially invite you to the > Upper Midwest Bearhawk BBQ and Cheese Extravaganza. It's just a get > together of builders and flying Bearhawks here in the Upper Midwest. It's > in Medford, WI at KMDZ. The official time and date will get posted on the > Bearhawk group. I host it usually the first week of October because the > leaves are turning and the weather is still good, but I had to delay it this > year due to my wife's pregnancy and some complications. Look for the new > date soon! http://groups.yahoo.com/group/Bearhawk/ > > 2) Whacha gonna Tig weld? Most builders are using gas for the reasons > specified here: http://www.tinmantech.com/html/faq__why_gas_over_tig_.php If > you want to use TIG it's up to you. I was just curious. > > Best of luck. Feel free to e-mail me off the list for any Bearhawk stuff > not related to the Mazda engine. > > Dwayne > > ------------------------------ > *From:* Dustin Lobner > *To:* Rotary motors in aircraft > *Sent:* Mon, November 8, 2010 7:52:42 AM > > *Subject:* [FlyRotary] Re: Current "state of the art" in rotaries - > potential Bearhawk install > > Barnstormers and trade-a-plane. By "decent" I mean "still has about 500 > hours before TBO"... I've also been looking into Continental O-470s because > 540s are harder to find as that's what the RV-10 crowd uses. > > Dustin > > On Mon, Nov 8, 2010 at 12:45 AM, Jeff Luckey wrote: > >> Dustin, >> >> >> >> Where did you find a decent O-540 for $15k? I have not looked in a while >> but you may find a decent O-360 in that price range, but an O-540 will >> probably be twice that??? >> >> >> >> >> ------------------------------ >> >> *From:* Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] *On >> Behalf Of *Tracy >> *Sent:* Sunday, November 07, 2010 11:13 >> *To:* Rotary motors in aircraft >> *Subject:* [FlyRotary] Re: Current "state of the art" in rotaries - >> potential Bearhawk install >> >> >> >> Hi Dustin, >> Answering the broad "what should I do " question is always a tall >> order. But in general, if you want a reliable 300HP your only option is a >> 20B. The 'all aluminum' version would be great (if it's real) but I doubt >> you could hit your target of $15K with that. Forget about 90+% of the car >> racer mods and just go with mild street porting. The peak loads we place >> on the engine are way less than a drag race application so the extra dowels >> are not necessary. The 20B in my RV-8 was built from mostly 13B parts >> except for the 20B center housing, crank and tension bolts. No other >> significant mods other than mild street port. Ceramic coating of the rotors >> is fine if done right but it has nothing to do with avoiding detonation. >> Use the 89 - 91 13B 9.7 : 1 CR rotors if possible. >> >> Tracy >> >> On Sun, Nov 7, 2010 at 1:15 PM, Dustin Lobner wrote: >> >> Hi everyone! >> >> This is my first message here. My name is Dustin, I live in the Rockford >> area in Illinois. I'm going to be starting a Bearhawk in the next couple of >> months and am strongly considering a rotary conversion for it...it'll be a >> few years before I'm at the "need an engine" point, but I want to know what >> I want to do before I get there, hence research now. The three sentence >> background on the Bearhawk: It's a 4-place utility/STOL aircraft that's >> pretty much my dream plane. Typical engine installs are O-360s and O-540, >> max HP set at 260HP due to the weight of a 300 HP Lycoming. I'd be >> comfortable running about 300HP on it, with a max complete engine weight of >> 400 pounds. >> >> I'm a metallurgical engineer at an aerospace company here in town. This, >> along with family, keep me very busy. As such, I'm interested in as close >> to a "turnkey" option that I can get (without forking over $+60k for >> something like a Mistral). I have extensive experience working on cars and >> motorcycles (and several friends who have a lot more), none working on a >> rotary though. I also have welding experience and will be buying a TIG >> welder as part of this project. >> >> With all that in mind, how I want this to work out is to buy the big >> pieces and bolt them together and work out things like intake, exhaust, >> etc. I'm an engineer, I do like figuring out how to do stuff and >> engineering solutions to problems...but I worry about never finishing, hence >> wanting people who know what they are doing to make the big parts. >> >> On with the questions... >> >> #1a) I'd like to have an engine builder build me a "core engine", minus >> EFI, intake, exhaust, etc. Any recommended builders out there? >> #1b) I emailed the folks at www.rotaryengine.com. I laid out my >> requirements and asked "what do you think I should do?" They aren't an >> aviation engine builder, so it'll be interesting to see what they come back >> with. In particular, they have all-aluminum engines (they bill themselves >> as the "home of the 3 rotor all-aluminum engine"). Any thoughts on them as >> a company or on the all-aluminum concept? >> #2) I was planning on using Tracy's ECI3/EMS3/RD-1C reduction drive. I >> see that Tracy is active here, which is awesome. (Tracy, you seem like a >> nice guy, so no offense intended on the next statement here): Are there any >> other viable options for a rotary reduction or ECI/EMS system out there? >> #3) Are there any recommended modifications to the engine to make it more >> reliable? There are a ton of things recommended by www.rotarengine.com(who sells the stuff, so take it with a pound of salt). These things >> include ceramic coatings of rotors to prevent detonation, various porting >> mods, oil-flow enhancement, cooling flow enhancement, installation of more >> dowel pins, etc. >> >> I had (somewhat arbitrarily) set the cost I was willing to spend at $15k, >> about the cost of a decent used Lycoming O-540. If the cost of this can >> stay below that, awesome. I'd rather spend a bit more and get something >> "done right" than skimp and then have an engine or redrive blow up on me. >> >> Tracy, I sent you an email with most of the above laid out. Feel free to >> ignore it, reply here if you wish. >> >> Thanks in advance for any replies! >> >> Dustin >> >> >> > > > --001517478bf09805950494aabb09 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Dwayne,

Thanks for the reply (and everyone else out there!)

I= do eventually plan on putting it on floats.=A0 Not initially, but that is = the eventual plan.

I read Tracy's comments on the redrive...from= a gutcheck, I prefer what Performance did by tightening tolerances instead= of loosening them, but a) I'm not an ME, so what do I know? and 2) if = Tracy's works, that's proof right there, isn't it?=A0 Not to me= ntio the cost difference.

Fuel system-wise I have a pretty good system in my head right now (I th= ink), I'll get it onto paper soon.

I'm on the Bearhawk Yahoo= group, haven't been on lately though.=A0 I'll certainly try and ma= ke it to the cookout, please shoot me an email if you think about it when i= t comes around.

TIG weld?=A0 Everything! (steel and aluminum alike).=A0 I'm a metal= lurgist, I prefer TIG for a variety of reasons (cleanliness, controllabilit= y, repeatability, can do it on aluminum).=A0 Not to mention, I have fairly = extensive experience with TIG (GTAW nowadays) one steel and aluminum (and s= tainless) and zero with flame...it's a comfort factor thing.

Dustin



On Mon, Nov 8, 2010 at= 12:51 PM, Dwayne Parkinson <dwayneparkinson@yahoo.com> wrote:
Dustin,

I don't know your goals or motivation for 300 hp,= but there are usually two reasons for lots of HP in a Bearhawk, floats and= /or speed. =A0

Using some rather loose math here's h= ow I think the Bearhawk works. =A0The cruise speeds posted by Pat Fagan and= others using the O-540 are based on a 250 HP O-540. =A0They're flying = at 65% so using simple math that's 162 HP in cruise to get 165 MPH or almost = 1 to 1 ratio of HP to MPH. =A0A 180 HP engine running at 65% is producing a= round 117 HP and is getting around 135 MPH or about a 1.15 ratio. =A0 I don= 't recall the exact numbers but someone also posted cruise speeds at 75= % and 85% as well. =A0When charting everything together, what's interes= ting is that as you increase HP beyond 162 there is a rapid decrease in the= MPH returned per HP, mostly due to the draggy nature of the airplane. =A0M= y observation here is that reducing drag will yield a bigger pay back than = increasing HP once we get beyond 162 HP. =A0
Now let's look at a rotary and see how it changes the game.= =A0First, you'll need either a three rotor, a turbo two rotor or (hope= fully) the new 16X to get a reasonable and reliable 162 HP in cruise. =A0No= w assuming you put some wheel pants on the plane, the game changer in terms of drag is th= e cooling drag. =A0The rotary allows some design flexibility to reduce that= . =A0Compare the slippery nose of a Cirrus or a Corvalis to the nose of tra= ditional Bearhawk designs including the big square oil cooler hanging down.= =A0There are some serious gains to be made there. =A0So assuming you take = advantage of that, the same 162 HP produced by a rotary and an O-540 will r= esult in a higher cruise speed for the rotary.

Now if we look at floats, it's a simi= lar and much simpler story. =A0We want to add as much HP per weight as poss= ible. =A0The three rotor solution comes in at about the same weight and sli= ghtly higher HP than an O-540. =A0BTW - I think the weight limit is 500 lbs on a Bearhawk for =A0the engine. =A0If you're open to rotary engin= es then the three rotor is the winner because of the higher HP.

Now on to your questions:

1a) =A0Bruce Turrentine comes highly rated as a builder but I h= aven't worked with him. =A0http://www.rotaryaviation.com/cus= tom_mazda_engines.html
1b) =A0The all aluminum concept sure sounds appealing but what are we trying to achieve? =A0Is it more power for less = weight? =A0Consider that in all=A0l= ikelihood, Mazda will release their= 16X before you're ready for an engine. =A0=A0http= ://www.mazda.com/mazdaspirit/rotary/16x/=A0=A0One less rot= or, less oil consumption, aluminum side housings, better fuel consumption a= nd most importantly it=A0theoretica= lly=A0delivers that O-540 level of 162 HP in cruise yet it weighs in at less than an IO-360.
2) I'd be careful regarding redrives and= get as much info as possible. =A0I'm no expert but I found Tracy's= "design philosophy" part 1, 2 and 3 very interesting info. =A0http://w= ww.rotaryaviation.com/psru_development.htm=A0=A0You've probably already read it, but = at the very least, other manufacturers ought to speak to the same points of= concern before their parts get the privilege of becoming a critical compon= ent of your airplane. =A0
3) Regarding reliability, my concern would be focused les= s on the engine and more on the fact that experimental airplane crashes are= most often caused by fuel system and cooling failures. =A0Fuel system and = cooling are common topics of discussion here for a reason. =A0Draw your own= conclusions, but if you're going with an experimental engine I'd b= e very very=A0diligent=A0with these two areas.=A0

Finally two other things:

<= /div>
1) =A0As a fellow Bearhawk builder, I'd like to = officially invite you to the Upper Midwest Bearhawk BBQ and Cheese Extravag= anza. =A0It's just a get together of builders and flying Bearhawks here= in the Upper Midwest. =A0It's in Medford, WI at KMDZ. =A0The official = time and date will get posted on the Bearhawk group. =A0I host it usually t= he first week of October because the leaves are turning and the weather is = still good, but I had to delay it this year due to my wife's pregnancy = and some complications. =A0Look for the new date soon! =A0 =A0http= ://groups.yahoo.com/group/Bearhawk/=A0=A0

2) =A0Whacha gonna Tig weld? =A0Most= builders are using gas for the reasons specified here: =A0http://www.tinmantech.com/html/faq__why_gas_over_tig_.php= =A0=A0If you want to use TIG it's up to you. =A0I was just curious.

Best of luck. =A0Feel free to e-mail me off the li= st for any Bearhawk stuff not related to the Mazda engine.

Dwayne

From: Dustin Lobner <dmlobner@gmail= .com>
To: Rotary= motors in aircraft <flyrotary@lancaironline.net>
Sent: Mon, November 8, 201= 0 7:52:42 AM

Subject: [FlyRotary] Re: Current "state of the= art" in rotaries - potential Bearhawk install

Barnstormers and trade-a-plane.=A0 By "decent" I mean "still= has about 500 hours before TBO"...=A0 I've also been looking into= Continental O-470s because 540s are harder to find as that's what the = RV-10 crowd uses.

Dustin

On Mon, Nov 8, 2010 at 12:45 A= M, Jeff Luckey <JLuckey@pacbell.ne= t> wrote:

Dustin,=

=A0

Where did you = find a decent O-540 for $15k?=A0 I have not looked in a while but you may find a decent O-360 in that price range, but an O-540 will probably be twice that???

=A0

=A0

From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Tracy
Sent: Sunday, November 07,= 2010 11:13
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: C= urrent "state of the art" in rotaries - potential Bearhawk install

=A0

Hi Dustin,
=A0=A0 Answering the broad=A0 "what should I do " question is always a tall order. =A0 But in general, if you want a reliable 300HP your only option is a 20B.=A0 The 'all aluminum' version would be g= reat (if it's real) but I doubt you could hit your target of=A0 $15K with that.= =A0 Forget about 90+% of the car racer mods and just go with mild street portin= g. =A0 The peak loads we place on the engine are way less than a drag race application so the extra dowels are not necessary.=A0=A0 The 20B in my RV-8 was built from mostly 13B parts except for the 20B center housing, cra= nk and tension bolts.=A0 No other significant mods other than mild street port.=A0 Ceramic coating of the rotors is fine if done right but it has nothing to do with avoiding detonation.=A0=A0 Use the 89 - 91 13B=A0 9.7 : 1 CR rotors if possible.

Tracy

On Sun, Nov 7, 2010 at 1:15 PM, Dustin Lobner <dmlobner@gmail.com> wrote:

Hi everyone!

This is my first message here.=A0 My name is Dustin, I live in the Rockford= area in Illinois.=A0 I'm going to be starting a Bearhawk in the next couple of months and am strongly considering a rotary conversion for it...it'll be a few years = before I'm at the "need an engine" point, but I want to know what I = want to do before I get there, hence research now.=A0 The three sentence background on the Bearhawk: It's a 4-place utility/STOL aircraft that's pretty= much my dream plane.=A0 Typical engine installs are O-360s and O-540, max HP set at 260HP due to the weight of a 300 HP Lycoming.=A0 I'd be comfortable run= ning about 300HP on it, with a max complete engine weight of 400 pounds.

I'm a metallurgical engineer at an aerospace company here in town.=A0 T= his, along with family, keep me very busy.=A0 As such, I'm interested in as = close to a "turnkey" option that I can get (without forking over $+60k = for something like a Mistral).=A0 I have extensive experience working on cars and motorcycles (and several friends who have a lot more), none working on = a rotary though.=A0 I also have welding experience and will be buying a TIG welder as part of this project.

With all that in mind, how I want this to work out is to buy the big pieces= and bolt them together and work out things like intake, exhaust, etc.=A0 I'= m an engineer, I do like figuring out how to do stuff and engineering solutions = to problems...but I worry about never finishing, hence wanting people who know what they are doing to make the big parts.

On with the questions...

#1a) I'd like to have an engine builder build me a "core engine&qu= ot;, minus EFI, intake, exhaust, etc.=A0 Any recommended builders out there?
#1b) I emailed the folks at www.rotaryengine.com.=A0 I laid out my requ= irements and asked "what do you think I should do?"=A0 They aren't an avia= tion engine builder, so it'll be interesting to see what they come back with= .=A0 In particular, they have all-aluminum engines (they bill themselves as the "home of the 3 rotor all-aluminum engine").=A0 Any thoughts on them as a company or on the all-aluminum concept?
#2) I was planning on using Tracy's ECI3/EMS3/RD-1C reduction drive.=A0 I see that Tracy is active here, which = is awesome.=A0 (Tracy, you seem like a nice guy, so no offense intended on the next statement here): A= re there any other viable options for a rotary reduction or ECI/EMS system out there?
#3) Are there any recommended modifications to the engine to make it more reliable?=A0 There are a ton of things recommended by www.rotarengine.com (who sells the stuff, so take it with a pound of salt).=A0 These things include ceramic coatings of rotors to prevent detonation, various porting mods, oil-flow enhancement, cooling flow enhancement, installation of more dowel pins, etc.

I had (somewhat arbitrarily) set the cost I was willing to spend at $15k, a= bout the cost of a decent used Lycoming O-540.=A0 If the cost of this can stay below that, awesome.=A0 I'd rather spend a bit more and get something "done right" than skimp and then have an engine or redrive blow u= p on me.

Tracy, I sent you an email with most of the above laid out.=A0 Feel free to ignore it, reply here if you wish.

Thanks in advance for any replies!

Dustin

=A0




--001517478bf09805950494aabb09--