Return-Path: Sender: "Marvin Kaye" To: lml@lancaironline.net Date: Fri, 04 Mar 2005 11:09:45 -0500 Message-ID: X-Original-Return-Path: Received: from lakermmtao12.cox.net ([68.230.240.27] verified) by logan.com (CommuniGate Pro SMTP 4.3c2) with ESMTP id 769916 for lml@lancaironline.net; Fri, 04 Mar 2005 09:48:07 -0500 Received-SPF: none receiver=logan.com; client-ip=68.230.240.27; envelope-from=Walter@advancedpilot.com Received: from [10.0.1.3] (really [68.227.132.71]) by lakermmtao12.cox.net (InterMail vM.6.01.04.00 201-2131-118-20041027) with ESMTP id <20050304144719.ZYOR2476.lakermmtao12.cox.net@[10.0.1.3]> for ; Fri, 4 Mar 2005 09:47:19 -0500 Mime-Version: 1.0 (Apple Message framework v619.2) In-Reply-To: References: Content-Type: multipart/alternative; boundary=Apple-Mail-3-643937615 X-Original-Message-Id: <6535aa44db58b2985f8a6b4dcc325e07@advancedpilot.com> From: W Atkinson Subject: Re: [LML] Re: FADEC Rough idle explanation X-Original-Date: Fri, 4 Mar 2005 08:47:20 -0600 X-Original-To: "Lancair Mailing List" X-Mailer: Apple Mail (2.619.2) --Apple-Mail-3-643937615 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=ISO-8859-1; format=flowed Matt: With all due respect, you have made some inaccurate assumptions. 1) I know how much fuel my tanks hold (usable) since I've run them dry=20= to find out. One needs to do this in flight to find out. 2) I have verified that my rate of burn is very accurate. It will=20 result in less than 1/2 gallon difference at any fill up. 3) I always plan a one hour reserve. I don't know too many pilots who=20= would chide me as being risky on that count. 4) My on-board totalizer is very accurate. 5) I know within a 1/2 gallon how much fuel is on board before I start=20= the flight. 6) I can check that the fuel burn IS what I think it is by running=20 tanks dry. 7) I cannot recall a flight in the last ten years where the fuel=20 remaining at landing was more than one gallon different than I=20 calculated it would be. You may not have that kind of accuracy. You may not trust it. YMMV,=20 but my experience confirms the accuracy of the information I have on=20 board. I get more use out of my airplane for my missions as a result.=20= This has been true in the last four airplanes I have owned. Walter On Mar 4, 2005, at 12:39 AM, Matt Hapgood wrote: Walter, =A0 You said that "[you] think that a good pilot always knows how much fuel=20= he has."=A0 =A0 I respectfully=A0disagree and I think YOU are on the slippery slope.=A0=A0= I=20 think a that a good pilot realizes that he DOESN'T=A0know=A0how much = fuel=20 he has, that he MAY have less than he thinks, and therefore plans=20 conservatively.=A0 =A0 It's the pilot who thinks he has better information than he really does=20= that is more likely to get dead than the conservative pilot.=A0=A0 In = fact,=20 I'm not sure I'd feel comfortable flying with someone who thinks they=20 have more accuracy in their remaining fuel=A0than=A0than they probably = do.=A0 =A0 Knowing how much fuel you have in flight requires knowing TWO things:=20 1) Burn rate, and 2) Starting usable fuel amount (and knowing how much=20= fuel a specific flight will require adds in many more variables). =A0 Unless=A0I have TOPPED my tanks on a completely LEVEL tarmac,=A0even=20 perfectly accurate fuel flow=A0doesn't really do much for me.=A0=20 Because=A0the bigger issue=A0is "How much fuel did I have to start with"=20= (does Tony D. come to mind?)?=A0 =A0 And here's the meat of the issue and where I think we really disagree:=A0=20= Measuring fuel flow to +/-=A0.2 GPH doesn't=A0do squat.=A0 5 hours in = the air=20 doesn't even equal a gallon.=A0=A0It would be a minor miracle if you = could=20 look in your tanks,=A0sitting on=A0an average tarmac, and be within even = 2=20 gallons of accuracy.=A0 And if you think your fuel flow is +/- 1%,=20 under=A0the range of conditions in which=A0you fly,=A0then I certainly = don't=20 want to fly with you.=A0 So, how accurate are YOU trying to be with fuel=20= fuel flow and remaining fuel? =A0 Go ahead and measure with a micrometer and cut with a hatchet.=A0 I = won't=20 hold the piece of wood.=A0 =A0 And I CERTAINLY didn't say I don't=A0CARE about how much fuel I have or=20= how much I burn (please reread my=A0post).=A0=A0I am just realistic in=20= recognizing that I don't have perfect information, so I'll be=20 conservative.=A0 =A0 So I'll stick with my comment, which was: =A0 "I personally don't really care whether I burn 8 GPH or 9 GPH in=20 cruise.=A0 I'm not going to fuel plan that precisely.=A0 I can't.=A0 I = don't=20 always know whether I will fly at 6,000' or 12,000' and that makes a=20 WHOLE lot larger difference in fuel planning than leaning.=A0=A0And just = as=20 in the car, I'd land and fuel up if I got lower on fuel than expected=20 on a trip." =A0 Maybe you turbo guys are different - no matter what altitude you fly=20 you maintain the same cruise power setting.=A0 It's just one number to=20= remember.=A0 But that's not the case for us normally aspirated guys.=A0 = My=20 fuel flows vary significantly on EVERY flight.=A0 I don't care to=20 memorize every burn rate at every power setting.=A0 I make conservative=20= estimates for flight planning.=A0 =A0 Don't ask me my Lancairs burn rate - unless you just want a rough=20 estimate, and I won't ask what the actual gas mileage of your SUV is=20 (you'll probably reply that you drive a Honda Insight and=A0I'll look=20 really stupid). =A0 If you don't want to fly with me, I'm not offended.=A0 Happy flying. Matt =A0 =A0 =A0 --Apple-Mail-3-643937615 Content-Transfer-Encoding: quoted-printable Content-Type: text/enriched; charset=ISO-8859-1 Matt: With all due respect, you have made some inaccurate assumptions. 1) I know how much fuel my tanks hold (usable) since I've run them dry to find out. One needs to do this in flight to find out. 2) I have verified that my rate of burn is very accurate. It will result in less than 1/2 gallon difference at any fill up. 3) I always plan a one hour reserve. I don't know too many pilots who would chide me as being risky on that count. 4) My on-board totalizer is very accurate. 5) I know within a 1/2 gallon how much fuel is on board before I start the flight. 6) I can check that the fuel burn IS what I think it is by running tanks dry. 7) I cannot recall a flight in the last ten years where the fuel remaining at landing was more than one gallon different than I calculated it would be. You may not have that kind of accuracy. You may not trust it. YMMV, but my experience confirms the accuracy of the information I have on board. I get more use out of my airplane for my missions as a result. This has been true in the last four airplanes I have owned. Walter On Mar 4, 2005, at 12:39 AM, Matt Hapgood wrote: = Arial0000,0000,FFFFWalter, = Arial0000,0000,FFFF =A0 = Arial0000,0000,FFFFYou said that "[you]Times New = Roman think that a good pilot always knows how much fuel he has."=A0 Times New Roman =A0 = Arial0000,0000,FFFFI respectfully=A0disagree and I think YOU are on the slippery slope.=A0=A0I think a that a good pilot realizes that he DOESN'T=A0know=A0how much = fuel he has, that he MAY have less than he thinks, and therefore plans conservatively.=A0 = Arial0000,0000,FFFF =A0 = Arial0000,0000,FFFFIt's the pilot who thinks he has better information than he really does that is more likely to get dead than the conservative pilot.=A0=A0 In fact, I'm not sure I'd feel comfortable flying with someone who thinks they have more accuracy in their remaining fuel=A0than=A0than they probably do.=A0 =A0 = Arial0000,0000,FFFFKnowing how much fuel you have in flight requires knowing TWO things: 1) Burn rate, and 2) Starting usable fuel amount (and knowing how much fuel a specific flight will require adds in many more = variables). =A0 = Arial0000,0000,FFFFUnless=A0I have TOPPED my tanks on a completely LEVEL tarmac,=A0even perfectly accurate fuel flow=A0doesn't really do much for me.=A0 Because=A0the = bigger issue=A0is "How much fuel did I have to start with" (does Tony D. come to mind?)?=A0 = Arial0000,0000,FFFF =A0 = Arial0000,0000,FFFFAnd here's the meat of the issue and where I think we really disagree:=A0 Measuring fuel flow to +/-=A0.2 GPH doesn't=A0do squat.=A0 5 hours in = the air doesn't even equal a gallon.=A0=A0It would be a minor miracle if you could look in your tanks,=A0sitting on=A0an average tarmac, and be = within even 2 gallons of accuracy.=A0 And if you think your fuel flow is +/- 1%, under=A0the range of conditions in which=A0you fly,=A0then I = certainly don't want to fly with you.=A0 So, how accurate are YOU trying to be with fuel fuel flow and remaining fuel? = Arial0000,0000,FFFF=A0 = Arial0000,0000,FFFFGo ahead and measure with a micrometer and cut with a hatchet.=A0 I won't hold the piece of wood.=A0 = Arial0000,0000,FFFF =A0 = Arial0000,0000,FFFFAnd I CERTAINLY didn't say I don't=A0CARE about how much fuel I have or how much I burn (please reread my=A0post).=A0=A0I am just realistic in recognizing that I don't have perfect information, so I'll be conservative.=A0 = Arial0000,0000,FFFF=A0 = Arial0000,0000,FFFFSo I'll stick with my comment, which was: =A0 = Arial0000,0000,FFFF"I personally don't really care whether I burn 8 GPH or 9 GPH in cruise.=A0 I'm not going to fuel plan that precisely.=A0 I can't.=A0 I don't always know whether I will fly at 6,000' or 12,000' and that makes a WHOLE lot larger difference in fuel planning than leaning.=A0=A0And just as in the car, I'd land and fuel up if I got lower on fuel than expected on a trip." =A0 = Arial0000,0000,FFFFMaybe you turbo guys are different - no matter what altitude you fly you maintain the same cruise power setting.=A0 It's just one number to remember.=A0 But that's not the case for us normally aspirated guys.=A0 = My fuel flows vary significantly on EVERY flight.=A0 I don't care to memorize every burn rate at every power setting.=A0 I make conservative estimates for flight planning.=A0 =A0 = Arial0000,0000,FFFFDon't ask me my Lancairs burn rate - unless you just want a rough estimate, and I won't ask what the actual gas mileage of your SUV is (you'll probably reply that you drive a Honda Insight and=A0I'll look really stupid). =A0 = Arial0000,0000,FFFFIf you don't want to fly with me, I'm not offended.=A0 Happy = flying. = Arial0000,0000,FFFFMatt =A0 =A0 =A0 --Apple-Mail-3-643937615--