Return-Path: Received: from fed1rmmtao04.cox.net ([68.230.241.35] verified) by logan.com (CommuniGate Pro SMTP 4.2b8) with ESMTP id 337189 for flyrotary@lancaironline.net; Wed, 28 Jul 2004 15:31:04 -0400 Received-SPF: error receiver=logan.com; client-ip=68.230.241.35; envelope-from=daveleonard@cox.net Received: from davidandanne ([68.111.224.107]) by fed1rmmtao04.cox.net (InterMail vM.6.01.03.02.01 201-2131-111-104-103-20040709) with SMTP id <20040728193033.DRGJ11386.fed1rmmtao04.cox.net@davidandanne> for ; Wed, 28 Jul 2004 15:30:33 -0400 From: "DaveLeonard" To: "Rotary motors in aircraft" Subject: RE: [FlyRotary] Re: Dave's Turbo info Date: Wed, 28 Jul 2004 12:30:38 -0700 Message-ID: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_008A_01C4749E.B04A4A50" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1441 In-Reply-To: Importance: Normal This is a multi-part message in MIME format. ------=_NextPart_000_008A_01C4749E.B04A4A50 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit RE: [FlyRotary] Dave's Turbo infoYea, I just wanted to get those hours done so I could get back to the workshop. Now I can make the little changes that I would probably have otherwise done during the fly off period. Yes, I just let the flapper float. Exhaust gasses easily push it all the way open. I can make seemingly as much boost as I can handle. At 7.5k feet the wastgate is pretty much fully open above 25" MAP anyway. So I think I will put the actuator back on for now. Going to see a man about a TO4 manifild today. Dave Leonard Geez Dave, you've been one busy flyin' son-of-a-gun. This is great info. How many psi of boost were you able to produce with the wastegate disconnected? Did you just disconnect the wastegate linkage and let the flapper float freely? A few days ago I disconnected my broken actuator and wired the flapper wide open. Static ground runs showed that I could achieve 4 psi of boost at WOT. I'd planned to test in flight, but a fast approaching line of thunder cells, caused me to head home for the day and haven't been back up since. I'm too busy today and I expect in the next few days I should receive my new used actuator (thanks Bob) and e-Boost controller, so I'll probably install these before I fly it again. Keep the info coming. S. Todd Bartrim (I hope this kid isn't going to keep me waiting much longer?) Turbo 13B RX-9endurance C-FSTB http://www3.telus.net/haywire/RV-9/C-FSTB.htm "Imagination is more important than knowledge" -Albert Einstein -----Original Message----- From: Rotary motors in aircraft [SMTP:flyrotary@lancaironline.net] Sent: Sunday, July 25, 2004 8:20 PM To: Rotary motors in aircraft Subject: [FlyRotary] I just completed my 40 hr. exile to the desert and finally returned back to the workshop and home airport. What a relief and a great feeling. I also took my wife up for her first ride. Her major complaints were: it sounds funny, it kinda smells like gas (left over from an old fuel leak), its too bumpy, and it goes too fast :-). The last couple flights I took some more turbo data that is interesting. I went to 7500 (density alt 10800) with the stock waste gate actuator connected and collected data in level flight. I set a constant MAP and recorded the RPM and IAS. Then I increased MAP by 1" and waited for steady state and recorded again. I did this up to max prop RPM (2800), which was 30" MAP, 151 KIAS (173 KTAS), but only 168 Kts on the GPS (193mph). (Based on multi-direction GPS testing I think my ASI is reading about 5 Kts high). Anyway, then I disconnected the waste gate actuator and repeated the testing (waste gate is then always fully open). My theory is that back pressure from the turbo is making the engine work significantly harder than a n.a engine, and I hope to see higher RPM for a given MAP The good news is that I had more RPM and IAS at any given MAP. The difference was more pronounced at the lower MAPs, but generally there was about 1" MAP improvement in RPM up to about 26" where the two graphs merged. I guess this is about where the waste gate would be fully open even with the actuator. At the lower MAPs there seemed to be improved cooling as well. Now the bad news. It became very difficult to run lean of peak with the lack of an automatic waste gate actuator. Since boost is very dependant on RPM, even the small of pitch changes required to maintain level flight caused enough variation in RPM to significantly change the boost - i.e. slow down just a little, boost drops, less RPM, less boost etc.. and in about a second the engine quits running. Slightly increasing the mixture is not enough to get it back as by then the RPM s have really dropped. It usually took a significant increase in mixture to start the engine again. I'm even starting to get used to the sensation of my engine stopping (watch out Ed, I'm gaining on you in glider time). It was essentially impossible to run significantly lean of peak. Even at the higher manifold pressures the automatic (stock) wastegate controller did a much better job of smoothing out the variations in boost. With the waste gate actuator attached I can run WOT at 14.5k 150 deg lean of peak showing about 29" MAP. It is equally easy to control boost pressure (prevent over boost) with the throttle in either configuration. Also, when running rich of peak this rapid loss of power does not occur. The questions at this point are which configuration is better and is there a way to fix the leaning issue? Also, how much more improvement could I get by opening up the waste gate a little more? Perhaps removing the flapper valve? The answer to the configuration issue is found in the purpose of each flight. Local flights full of sightseeing and aerobatics would be better with the actuator off. Cross country would do better with the ability to aggressively lean at altitude. Perhaps I will eventually make it cockpit adjustable or better yet, just do it right and put on a huge turbo and wastegate. I already bought a TO4 from Bill.... Now to just make it all fit. Separate e-mail to follow with separate issues. David Leonard The Rotary Roster http://members.aol.com\_ht_a\rotaryroster\index.html << File: ATT1916502.txt >> ------=_NextPart_000_008A_01C4749E.B04A4A50 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable RE: [FlyRotary] Dave's Turbo info
Yea, = I just wanted=20 to get those hours done so I could get back to the workshop.  Now I = can=20 make the little changes that I would probably have otherwise done during = the fly=20 off period.
 
Yes, = I just let the=20 flapper float.  Exhaust gasses easily push it all the way = open.  I can=20 make seemingly as much boost as I can handle.  At 7.5k feet the = wastgate is=20 pretty much fully open above 25" MAP anyway.  So I think I will put = the=20 actuator back on for now.
 
Going = to see a man=20 about a TO4 manifild today.
 
Dave=20 Leonard

Geez Dave, you've = been one busy=20 flyin' son-of-a-gun. This is great info. How many psi of boost were = you able=20 to produce with the wastegate disconnected? Did you just disconnect = the=20 wastegate linkage and let the flapper float freely?

        A few days ago I disconnected my broken actuator = and wired=20 the flapper wide open. Static ground runs showed that I could achieve = 4 psi of=20 boost at WOT. I'd planned to test in flight, but a fast approaching = line of=20 thunder cells,  caused me to head home for the day and haven't = been back=20 up since. I'm too busy today and I expect in the next few days I = should=20 receive my new used actuator (thanks Bob) and e-Boost controller, so = I'll=20 probably install these before I fly it again.

        Keep the info coming.

S. Todd Bartrim=20         (I hope this kid isn't = going to=20 keep me waiting much longer?)
Turbo 13B
RX-9endurance
C-FSTB
http://www3.telus.= net/haywire/RV-9/C-FSTB.htm=20

        "Imagination is more important than = knowledge"=20
       =20        =20        =20        =20         -Albert=20 Einstein


    -----Original=20 Message-----
    From:   Rotary motors in=20 aircraft [SMTP:flyrotary@lancaironline.net]
    Sent:   Sunday, July 25, 2004 8:20 PM =
    To:    =20 Rotary motors in aircraft =
    Subject:        = [FlyRotary]

    I just completed = my 40 hr. exile=20 to the desert and finally returned back to
    the workshop and home = airport.  What=20 a relief and a great feeling.  I also
    took my wife up for her = first ride. =20 Her major complaints were: it sounds
    funny, it kinda smells like = gas (left=20 over from an old fuel leak), its too
    bumpy,  and it goes = too fast=20 :-).   

    The last couple = flights I took=20 some more turbo data that is interesting.

    I went to 7500 = (density alt=20 10800) with the stock waste gate actuator
    connected and collected = data in level=20 flight.  I set a constant MAP and
    recorded the RPM and = IAS.  Then I=20 increased MAP by 1" and waited for steady
    state and recorded = again.  I did=20 this up to max prop RPM (2800), which was
    30" MAP, 151 KIAS (173 = KTAS), but only=20 168 Kts on the GPS (193mph).  (Based
    on multi-direction GPS = testing I think my=20 ASI is reading about 5 Kts high).


    Anyway, then I = disconnected the=20 waste gate actuator and repeated the testing
    (waste gate is then always = fully=20 open).  My theory is that back pressure
    from the turbo is making = the engine work=20 significantly harder than a n.a
    engine, and I hope to see higher RPM for a = given=20 MAP

    The good news is = that I had more=20 RPM and IAS at any given MAP.  The
    difference was more = pronounced at the=20 lower MAPs, but generally there was
    about 1" MAP improvement in RPM up to about = 26" where the=20 two graphs merged.
    I guess this is about where the waste gate would be fully = open even=20 with the
    actuator.  At the lower MAPs there seemed to be = improved cooling=20 as well.

    Now the bad = news.  It=20 became very difficult to run lean of peak with the =
    lack of an automatic waste = gate=20 actuator.  Since boost is very dependant on =
    RPM, even the small of = pitch changes=20 required to maintain level flight
    caused enough variation in RPM to = significantly change the=20 boost - i.e. slow
    down just a little, boost drops, less RPM, less boost etc.. = and in=20 about a
    second=20 the engine quits running.  Slightly increasing the mixture is=20 not
    enough to get=20 it back as by then the RPM s have really dropped.  It=20 usually
    took a=20 significant increase in mixture to start the engine again.  I'm = even
    starting to=20 get used to the sensation of my engine stopping (watch out = Ed,=20
    I'm gaining on = you in glider=20 time).  It was essentially impossible to run =
    significantly lean of = peak.  Even at=20 the higher manifold pressures the
    automatic (stock) wastegate controller did a = much better=20 job of smoothing
    out the variations in boost.  With the waste gate = actuator=20 attached I can
    run WOT at 14.5k 150 deg lean of peak showing about 29" = MAP.  It=20 is equally
    easy=20 to control boost pressure (prevent over boost) with the throttle=20 in
    either=20 configuration.  Also, when running rich of peak this rapid loss = of
    power does not=20 occur.

    The questions at = this point are=20 which configuration is better and is there a
    way to fix the leaning = issue?  Also,=20 how much more improvement could I get
    by opening up the waste = gate a little=20 more?  Perhaps removing the flapper
    valve?  The answer to = the=20 configuration issue is found in the purpose of =
    each flight.  Local = flights full of=20 sightseeing and aerobatics would be
    better with the actuator off.  Cross = country would do=20 better with the
    ability to aggressively lean at altitude.  Perhaps I = will=20 eventually make it
    cockpit adjustable or better yet, just do it right and put = on a huge=20 turbo
    and=20 wastegate.  I already bought a TO4 from Bill.... Now to just = make it=20 all
    fit.

    Separate e-mail to = follow with=20 separate issues.

    David = Leonard=20
    The Rotary = Roster=20
    http://memb= ers.aol.com\_ht_a\rotaryroster\index.html=20
     << = File:=20 ATT1916502.txt >> =

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