X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from cdptpa-omtalb.mail.rr.com ([75.180.132.120] verified) by logan.com (CommuniGate Pro SMTP 6.0.6) with ESMTP id 6460134 for flyrotary@lancaironline.net; Mon, 09 Sep 2013 10:03:51 -0400 Received-SPF: pass receiver=logan.com; client-ip=75.180.132.120; envelope-from=eanderson@carolina.rr.com Return-Path: X-Authority-Analysis: v=2.0 cv=N7qr5hBB c=1 sm=0 a=8784VxN1RgZhBaSzA3ibpA==:17 a=KWPSR_H0u7wA:10 a=InldE9ZqYiAA:10 a=05ChyHeVI94A:10 a=ayC55rCoAAAA:8 a=KGjhK52YXX0A:10 a=RjT5VLY-GEEA:10 a=3oc9M9_CAAAA:8 a=oCcaPWc0AAAA:8 a=aYBryqvIecPCllu-Ch0A:9 a=QEXdDO2ut3YA:10 a=U8Ie8EnqySEA:10 a=0q_9Y0hHjcwA:10 a=pGLkceISAAAA:8 a=Ia-xEzejAAAA:8 a=-ULVeYTQM7sFj6tUFRwA:9 a=_W_S_7VecoQA:10 a=MSl-tDqOz04A:10 a=EzXvWhQp4_cA:10 a=uLmefG2xzxLTYm-T:21 a=8784VxN1RgZhBaSzA3ibpA==:117 X-Cloudmark-Score: 0 X-Authenticated-User: X-Originating-IP: 174.110.171.30 Received: from [174.110.171.30] ([174.110.171.30:63156] helo=EdPC) by cdptpa-oedge04.mail.rr.com (envelope-from ) (ecelerity 2.2.3.46 r()) with ESMTP id A9/0B-21526-425DD225; Mon, 09 Sep 2013 14:03:16 +0000 Message-ID: <60D35DF8A41F4DE880ADE5CC61BFD053@EdPC> From: "Ed Anderson" To: "Rotary motors in aircraft" References: In-Reply-To: Subject: Re: [FlyRotary] Re: First Flight jitters Date: Mon, 9 Sep 2013 10:01:52 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_003D_01CEAD43.9B7B3480" X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 16.4.3508.205 X-MimeOLE: Produced By Microsoft MimeOLE V16.4.3508.205 This is a multi-part message in MIME format. ------=_NextPart_000_003D_01CEAD43.9B7B3480 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable What Tracy said about prop chord. Had a friend who spent months trying to get his Renesis above 5000 rpm = =E2=80=93 confirmed that he had a 74x88 prop =E2=80=93 same as mine. = Later on during my first visit =E2=80=93 it was very clear what the = problem was. His diameter and pitch were the same, however his prop = chord was on the order of 8=E2=80=9D whereas mine was around 5 = 1/4=E2=80=9D. We put my prop on his engine and he had no problem = getting 6000 + rpm. So measure your chord and let us know. Ed From: Tracy=20 Sent: Monday, September 09, 2013 4:57 AM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: First Flight jitters You are either over propped or something is wrong with the engine or = tuning. At 37" mp you should be in the 5500-6000 rpm range. You = didn't give the rpm at 16" mp and 11 deg BTDC so I can't tell if timing = is in the ballpark or not. Is that the same rpm as your hat blew off = (3000)? If so, you may be too retarded. And of course we need your prop numbers to make a guess about anything. = Prop chord at 70% on blade is good to know too. Do you have one of = those wide chord airboat type props? Tracy Sent from my iPad On Sep 9, 2013, at 0:47, shipchief@aol.com wrote: I've been slowly building my RV-8 with 13BT engine for about 14 = years...! On June 13th 2013 it received the coveted Airworthiness Certificate. = That same day I detonated my engine due to the trailing spark plug holes = being machined oversize in an attempt to improve the single spark plug = power, should the leading plug ignition fail. This, and possibly = advanced ignition, and possibly over-boost detonated my engine on it's = first high power taxi test. That took about 2.5 seconds. Now I've rebuilt the engine with new unmodified rotor housings, and it = runs better than ever. I've re-marked the timing marks on the pulley, = and reset the timing, though not to 4000 RPM yet. today I checked it. At = 3000 RPM my hat and hearing protection blew off. 11 degrees BTDC, and = 16" manifold pressure. I've been taxiing around at modest RPM, it's great. I've consistently = been idling at about 1600 RPM, (730 prop RPM) and sometimes as low as = 1490, (680 Prop RPM) smoothly. That is slow enough to keep the brakes = from getting too hot. I've done run ups and brief bursts of power to 4200 Engine RPM, (1917 = Prop RPM) which is about 32" manifold pressure, and seen 37" manifold = pressure briefly. I know this is not enough power to take off, although = I have done a Pre-take off to 50 MPH with this power before powering = down with roll out to the end of the runway. I suppose it would fly off = and maybe clear the trees at this power. I've lifted the tail, and = rocked the wings with the ailerons. It steers well and the brakes work.=20 The water level in the engine stays up between flights as does the = oil, and the water temp today was consistent 163 F oil about 173 with = the highest observed 183F. I did about 4 pre-take off passes with taxi = back, with excellent temperature control and throttle response.=20 A couple of oil fitting were tightened looking for an oil seep. 7.3 hours engine running time on the EM2, about 2 hours since the = engine overhaul. I don't think I'm at all ready to fly this thing. I'm missing = something, so offer up some advice, I'm all ears! No virus found in this message. Checked by AVG - www.avg.com Version: 2013.0.3392 / Virus Database: 3222/6649 - Release Date: = 09/09/13 ------=_NextPart_000_003D_01CEAD43.9B7B3480 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
What Tracy said about prop chord.
 
Had a friend who spent months trying to get his Renesis above 5000 = rpm =E2=80=93=20 confirmed that he had a 74x88 prop =E2=80=93 same as mine.  Later = on during my=20 first visit =E2=80=93 it was very clear what the problem was.  His = diameter and=20 pitch were the same, however his  prop chord was on the order of = 8=E2=80=9D whereas=20 mine was around 5 1/4=E2=80=9D.  We put my prop on his engine and = he had no problem=20 getting 6000 + rpm.  So measure your chord and let us know.
 
Ed
 
From: Tracy
Sent: Monday, September 09, 2013 4:57 AM
Subject: [FlyRotary] Re: First Flight = jitters
 
You are either over propped or something is wrong with the engine = or=20 tuning.   At 37" mp you should be in the 5500-6000  rpm=20 range.   You didn't give the rpm at 16" mp and 11 deg BTDC so = I can't=20 tell if timing is in the ballpark or not.  Is that the same rpm as = your hat=20 blew off (3000)?  If so, you may be too retarded.
 
And of course we need your prop numbers to make a guess about=20 anything.  Prop chord at 70% on blade is good to know too.  Do = you=20 have one of those wide chord airboat type props?
 
Tracy

Sent from my iPad

On Sep 9, 2013, at 0:47, shipchief@aol.com = wrote:

I've been slowly = building my=20 RV-8 with 13BT engine for about 14 years...!
On June 13th 2013 it received the coveted Airworthiness = Certificate. That=20 same day I detonated my engine due to the trailing spark plug holes = being=20 machined oversize in an attempt to improve the single spark plug = power, should=20 the leading plug ignition fail. This, and possibly advanced ignition, = and=20 possibly over-boost detonated my engine on it's first high power taxi = test.=20 That took about 2.5 seconds.
Now I've rebuilt the engine with new unmodified rotor housings, = and it=20 runs better than ever. I've re-marked the timing marks on the pulley, = and=20 reset the timing, though not to 4000 RPM yet. today I checked it. At = 3000 RPM=20 my hat and hearing protection blew off. 11 degrees BTDC, and 16" = manifold=20 pressure.
I've been taxiing around at modest RPM, it's great. I've = consistently=20 been idling at about 1600 RPM, (730 prop RPM) and sometimes as low as = 1490,=20 (680 Prop RPM) smoothly. That is slow enough to keep the brakes from = getting=20 too hot.
I've done run ups and brief bursts of power to 4200 Engine RPM, = (1917=20 Prop RPM) which is about 32" manifold pressure, and seen 37" manifold = pressure=20 briefly. I know this is not enough power to take off, although I have = done a=20 Pre-take off to 50 MPH with this power before powering down with roll = out to=20 the end of the runway.  I suppose it would fly off and maybe = clear the=20 trees at this power. I've lifted the tail, and rocked the wings with = the=20 ailerons. It steers well and the brakes work.
The water level in the engine stays up between flights as does = the oil,=20 and the water temp today was consistent 163 F oil  about 173 with = the=20 highest observed 183F. I did about 4 pre-take off passes with taxi = back, with=20 excellent temperature control and throttle response.
A couple of oil fitting were tightened looking for an oil = seep.
7.3 hours engine running time on the EM2, about 2 hours since the = engine=20 overhaul.
I don't think I'm at all ready to fly this thing. I'm missing = something,=20 so offer up some advice, I'm all = ears!

No virus found in this=20 message.
Checked by AVG - www.avg.com
Version: 2013.0.3392 / = Virus=20 Database: 3222/6649 - Release Date: = 09/09/13

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