X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from cdptpa-omtalb.mail.rr.com ([75.180.132.122] verified) by logan.com (CommuniGate Pro SMTP 5.3.9) with ESMTP id 4508864 for flyrotary@lancaironline.net; Sat, 16 Oct 2010 21:40:16 -0400 Received-SPF: pass receiver=logan.com; client-ip=75.180.132.122; envelope-from=eanderson@carolina.rr.com Return-Path: X-Authority-Analysis: v=1.1 cv=lu/RhtYP0ChAeUxMEPBris12a71TWT5f9yvo3GNwP9w= c=1 sm=0 a=rPkcCx1H5rrOSfN0dPC7kw==:17 a=C_IRinGWAAAA:8 a=ayC55rCoAAAA:8 a=Ia-xEzejAAAA:8 a=O3mtLqp2xp1ufPlPv3IA:9 a=rjGDrIdIjcyh7fECOkQA:7 a=J5spw4sx4l5zSGwaQvIDaQ_uzJQA:4 a=QEXdDO2ut3YA:10 a=si9q_4b84H0A:10 a=EzXvWhQp4_cA:10 a=mHWwRimNM_aVwFie:21 a=ROk_bVRRSvJPnyEP:21 a=W46spJs-HjiCZVJDB1MA:9 a=-GWjUj0E93ivPqhOga4A:7 a=Uo4LGLpDCl5MCuTfsLRLCHE8tGMA:4 a=Z3CGPm3ChSEomOxI:21 a=rNeS5dTVR--iM9rF:21 a=rPkcCx1H5rrOSfN0dPC7kw==:117 X-Cloudmark-Score: 0 X-Originating-IP: 174.110.167.5 Received: from [174.110.167.5] ([174.110.167.5:50313] helo=EdPC) by cdptpa-oedge02.mail.rr.com (envelope-from ) (ecelerity 2.2.3.46 r()) with ESMTP id 7C/E3-14228-CD35ABC4; Sun, 17 Oct 2010 01:39:41 +0000 Message-ID: <7ACA19B1D3F14F8F915251F4510B8630@EdPC> From: "Ed Anderson" To: "Rotary motors in aircraft" References: In-Reply-To: Subject: Re: [FlyRotary] Re: Test Date: Sat, 16 Oct 2010 21:39:19 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_002B_01CB6D7A.9712CAE0" X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 14.0.8117.416 X-MimeOLE: Produced By Microsoft MimeOLE V14.0.8117.416 This is a multi-part message in MIME format. ------=_NextPart_000_002B_01CB6D7A.9712CAE0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable RPM/Manifold Pressure correlation is not necessarily something that = jumps out at you at first, David But, when I noticed I could get 5500 rpm (without a prop - NOT = recommended) at idle throttle setting with manifold pressure around the = 14-15" Hg area - it told me that RPM by ITSELF was definitely NOT a = valid indicator of power. But, on the other hand, if your throttle is = wide open with 29.9X " Hg showing AND you are getting 6000 rpm then = your engine is cooking up a lot of power. =20 The other indicator you want to notice is your fuel flow at static WOT. = A conservative rule of thumb is that you should be flowing approx 10 GPH = for each 100 HP (you can flow more through a rotary and not gain = commensurate increase in power - but, you can not flow less than that = and make the power indicated by the rule of thumb). So if you are getting say 5900 RPM at 29.92 and are flowing around 15.5 = -16 GPH you are likely to be producing close to 160 - 165 HP or perhaps = a bit more. In any case, clearly enough to go flying safely on. Other indicators (such as dragging the truck with its parking brake on = {:>)) are just confirmation of what the data are telling you - or is it = vice versa? =20 It certainly would be interesting if there were a scale handy that you = could tie into your hold-down line and get readings at various rpm. Ed From: hoursaway1@comcast.net=20 Sent: Saturday, October 16, 2010 7:41 PM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: Test Never thought of the scale to measure poundage of thrust or pull, I may = be able to do that, will ask around. Thanks again for the tips & now = that you mention it never really ac-cured to me to look for MAP/RPM = correlation to power/thrust output, was mainly going by feel/accell from = launch & pull on the truck feels like she wants to go. David. ----- Original Message ----- From: "Ed Anderson" To: "Rotary motors in aircraft" Sent: Friday, October 15, 2010 5:12:40 PM Subject: [FlyRotary] Re: Test I know you will, David, but felt I had to speak up. Can never be to careful at any time with this hobby, but particularly in = the early part where you are still learning the aircraft and engine. = Sounds like you are certainly getting plenty of RPM and good manifold = pressure. I usually caution folks with adjustable props to be careful - = in that you can set the pitch to get wild rpm but insufficient thrust. =20 A gent I was acquainted with back in the late 1990s (electronic whiz - = sold modified auto ECUs for aircraft use), set his adjustable such that = he got lots of rpm, but unfortunately not enough thrust to propel him = safely out of ground effect. Crashed into a cactus because He could = never climb out of ground effect. But if you are getting 5950 at a load of 29.5 (WOT) then that tells me = you have the engine well loaded. If it were 5950 at say 20-22 inches I = would say you need to increase the bite (pitch) of the blades. However, = with that high a manifold pressure things look good to me.=20 Now if you would just put a 1000 lb fish scale in that line you have = tied to the truck, we could get some real thrust measurements {:>) Looking forward to hearing the results Ed From: hoursaway1@comcast.net=20 Sent: Friday, October 15, 2010 2:52 PM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: Test Thanks Ed, will do. Am getting 5950 RPM, 29.5 MAP static (tied to PU = truck) Ivo Prop three blade 68" elect. adjusted to fine pitch ( I think = I miss-spoke earlyer, another post, prop dia. of 72", our is 68", I do = have a 72" two blade, not using ). David = R. Cook RV6A Rotary. ----- Original Message ----- From: "Ed Anderson" To: "Rotary motors in aircraft" Sent: Friday, October 15, 2010 11:53:11 AM Subject: [FlyRotary] Re: Test Enough to get the old heart a pumping - I still recall it like = yesterday. Be careful on high speed taxi - always make certain you and aircraft = are ready for flight - even unintended flight. Some folks advocate NOT = doing high speed taxi test due to increased risk during that phase. I = recall one accident - where individual had not removed control locks - = because he was not going to fly, only do taxi test, well he = unintentionally lifted off - fortunately only damage to the airplane. I = know you won't do that, David, but just be prepared for flight in any = case.=20 Good luck Ed From: hoursaway1@comcast.net=20 Sent: Friday, October 15, 2010 11:31 AM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: Test Ok I'll say something;;; Insurance coverage for N655HC will be bound on = the 18th of this mth. so high speed taxing will get started, are running = the eng. high power w/cowel all in place testing for any cooling = problems, that starts sat. or this evening, now I need to get me up to = speed/airworthy. David R. Cook RV6A Rotary = Lansing MI. ----- Original Message ----- From: "Tracy Hallock (RR)" To: "Rotary motors in aircraft" Sent: Friday, October 15, 2010 10:12:41 AM Subject: [FlyRotary] Re: Test Yep, it's quiet, but mail is getting through. From: Dennis Havarlah=20 Sent: Friday, October 15, 2010 8:55 AM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Test Test - too Quiet ------=_NextPart_000_002B_01CB6D7A.9712CAE0 Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable
RPM/Manifold Pressure correlation is not = necessarily=20 something that jumps out at you at first, David
 
But, when I noticed I could get 5500 rpm = (without a prop -=20 NOT recommended) at idle throttle setting with manifold = pressure around the 14-15" Hg area - it told me that RPM by=20 ITSELF was definitely=20 NOT a valid indicator of power.  = But, on=20 the other hand, if your throttle is wide  open with 29.9X " Hg = showing=20 AND you are getting 6000 rpm then your engine is = cooking up a=20 lot of power. 
 
The other indicator you want to notice is your = fuel flow=20 at static WOT.  A conservative rule of thumb is that you should be = flowing=20 approx 10 GPH for each 100 HP (you can flow more through a rotary and = not gain=20 commensurate increase in power - but, you can not flow less than that = and make=20 the power indicated by the rule of thumb).
 
So if you are getting say 5900 RPM at 29.92 and = are=20 flowing around 15.5 -16 GPH you are likely to be producing close to = 160 -=20 165 HP or perhaps a bit more.  In any case, clearly enough to go = flying=20 safely on.
 
Other indicators (such as dragging the truck = with its=20 parking brake on {:>)) are just confirmation of what the data are = telling you=20 - or is it vice versa? 
 
It certainly would be interesting if there were = a scale=20 handy that you could tie into your hold-down line and get readings at = various=20 rpm.
 
 
Ed
 

From: hoursaway1@comcast.net
Sent: Saturday, October 16, 2010 7:41 PM
To: Rotary motors in = aircraft
Subject: [FlyRotary] Re: Test

Never = thought=20 of the scale to measure poundage of thrust or pull, I may be able to do = that,=20 will ask around.  Thanks again for the tips & now that you = mention it=20 never really ac-cured to me to look for MAP/RPM correlation to = power/thrust=20 output, was mainly going by feel/accell from launch & pull on the = truck=20 feels like she wants to go. David.
----- Original Message = -----
From: "Ed=20 Anderson" <eanderson@carolina.rr.com>
To: "Rotary motors in = aircraft"=20 <flyrotary@lancaironline.net>
Sent: Friday, October 15, 2010 = 5:12:40=20 PM
Subject: [FlyRotary] Re: Test

I know you will, David, but felt I had to speak=20 up.
 
Can never be to careful at any time with this = hobby, but=20 particularly in the early part where you are still learning the aircraft = and=20 engine.  Sounds like you are certainly getting plenty of RPM and = good=20 manifold pressure.  I usually caution folks with adjustable props = to be=20 careful - in that you can set the pitch to get wild rpm but insufficient = thrust. 
 
A gent I was acquainted with back in the late = 1990s=20 (electronic whiz - sold modified auto ECUs for aircraft use), set his = adjustable=20 such that he got lots of rpm, but unfortunately not enough thrust to = propel him=20 safely out of ground effect.  Crashed into a cactus because He = could never=20 climb out of ground effect.
 
But if you are getting 5950 at a load of 29.5 = (WOT) then=20 that tells me you have the engine well loaded.  If it were 5950 at = say=20 20-22 inches I would say you need to increase the bite (pitch) of the=20 blades.  However, with that high a manifold pressure things look = good to=20 me.
 
Now if you would just put a 1000 lb fish scale = in that=20 line you have tied to the truck, we could get some real thrust = measurements=20 {:>)
 
Looking forward to hearing the = results
 
Ed

Sent: Friday, October 15, 2010 2:52 PM
Subject: [FlyRotary] Re: Test

Thanks Ed, will=20 do.   Am getting  5950 RPM, 29.5 MAP static (tied to PU=20 truck)  Ivo Prop three blade 68" elect. adjusted to fine pitch ( I = think I=20 miss-spoke earlyer, another post, prop dia. of 72", our is 68", I do = have a 72"=20 two blade, not using=20 ).            = ;            =        =20 David R. Cook    RV6A Rotary.
----- Original Message=20 -----
From: "Ed Anderson" <eanderson@carolina.rr.com>
To: "Rotary motors = in=20 aircraft" <flyrotary@lancaironline.net>
Sent: Friday, October = 15, 2010=20 11:53:11 AM
Subject: [FlyRotary] Re: Test

Enough to get the old heart a pumping - I still = recall it=20 like yesterday.
 
 Be careful on high speed taxi - always = make certain=20 you and aircraft are ready for flight - even unintended flight.  = Some folks=20 advocate NOT doing high speed taxi test due to increased risk during = that=20 phase.   I recall one accident - where individual had not = removed=20 control locks - because he was not going to fly, only do taxi test, well = he  unintentionally lifted off - fortunately only damage to the=20 airplane.  I know you won't do that, David, but just be prepared = for flight=20 in any case.
 
Good luck
 
Ed
 
 

From: hoursaway1@comcast.net=20
Sent: Friday, October 15, 2010 11:31 AM
Subject: [FlyRotary] Re: Test

Ok = I'll say=20 something;;;  Insurance coverage for N655HC will be bound = on the=20 18th of this mth. so high speed taxing will get started, are running the = eng.=20 high power w/cowel all in place testing for any cooling problems, that = starts=20 sat. or this evening, now I need to get me up to=20 speed/airworthy.         &nb= sp;           &nbs= p; =20 David R. Cook  RV6A Rotary Lansing MI.
----- Original Message=20 -----
From: "Tracy Hallock (RR)" = <thallock2@austin.rr.com>
To:=20 "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Sent: = Friday,=20 October 15, 2010 10:12:41 AM
Subject: [FlyRotary] Re: Test

Yep, it's quiet, but mail is getting=20 through.
 
 

Sent: Friday, October 15, 2010 8:55 AM
Subject: [FlyRotary] Test

Test - too Quiet
 
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