X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Tue, 29 Dec 2009 12:53:38 -0500 Message-ID: X-Original-Return-Path: Received: from imr-ma03.mx.aol.com ([64.12.206.41] verified) by logan.com (CommuniGate Pro SMTP 5.3c4) with ESMTP id 4043015 for lml@lancaironline.net; Sun, 27 Dec 2009 16:40:59 -0500 Received-SPF: pass receiver=logan.com; client-ip=64.12.206.41; envelope-from=MikeEasley@aol.com Received: from imo-ma02.mx.aol.com (imo-ma02.mx.aol.com [64.12.78.137]) by imr-ma03.mx.aol.com (8.14.1/8.14.1) with ESMTP id nBRLeKmu010104 for ; Sun, 27 Dec 2009 16:40:20 -0500 Received: from MikeEasley@aol.com by imo-ma02.mx.aol.com (mail_out_v42.5.) id q.c99.5deac738 (37228) for ; Sun, 27 Dec 2009 16:40:16 -0500 (EST) Received: from MikeNotebook (c-75-71-55-189.hsd1.co.comcast.net [75.71.55.189]) by cia-ma06.mx.aol.com (v127.7) with ESMTP id MAILCIAMA065-916c4b37d43e89; Sun, 27 Dec 2009 16:40:15 -0500 X-Original-Date: Sun, 27 Dec 2009 14:40:14 -0700 From: mikeeasley Subject: Re: [LML] Re: Fuel Planning X-Original-To: "Lancair Mailing List" In-Reply-To: X-Original-Message-ID: <26ef15bd.a598.4cc1.81e6.bd704ef07a6f@aol.com> References: X-Mailer: Nexus Desktop Client 3.1.20.1 MIME-Version: 1.0 Content-Type: MULTIPART/alternative; BOUNDARY=84c00147-e25c-4134-b1a5-56ad870a4ad0 Content-Transfer-Encoding: 8bit X-AOL-IP: 75.71.55.189 X-Spam-Flag:NO X-AOL-SENDER: MikeEasley@aol.com --84c00147-e25c-4134-b1a5-56ad870a4ad0 Content-Type: TEXT/plain; charset=us-ascii I'll give you the "known quantity" definition. But just because the fuel is in your wing doesn't mean you are 100% sure it's available to burn, right? And a properly functioning, accurately calibrated capacitance probe and digital gage is significantly more accurate than the GA standard fuel gages I had in my 201. A couple things I do to confirm the functionality of my fuel gages is to do the math between the fuel flow reading, fuel tank levels, and how much fuel it takes to fill the tanks when I'm at the pump. Those little mental math exercises give me a reality check on a regular basis. For example: If I switch tanks in an hour, my left tank should be down to 30 gallons by then... If I switch tanks now, I should land with about 22 gallons in each tank... It should take about 35 gallons to fill the left tank and 30 gallons to fill the right tank... I completely lost my JPI EDM 900 a few years back, just went black about an hour into a flight. I landed and got it repaired before flying home. I knew I had a bunch of fuel on board and how long I'd been flying on the current tank because I keep good ol' tank switching notes on my flight plan sheet on my lap board. And I do visually check the fuel quantity in my tanks during my preflight, although I can't really tell very accurately how much I have unless the tanks are pretty full. Maybe a paint stick with some Sharpie marks might be a good thing to have for partially fueled flights. Mike Easley Colorado Springs In a message dated 12/27/09 10:51:27 Mountain Standard Time, gt_phantom@hotmail.com writes: I received two responses to my post; I am responding to both in this post. To both Grayhawk and Mike Easley I respectfully submit that you are asking for needless trouble. If you will refer to my original post, I did not say that "Full" was not the only POSSIBLE "known quantity, but rather that it was the only known quantity for each tank on most Lancairs. That is a FACTUAL statement, your arguments about the reliability of your respective fuel gauges notwithstanding. Do you visually confirm that the amount of fuel in each tank matches what the gauge says, and if so, how? Capacitance gauges, while very accurate today, do have failure modes. Do you know all of them? Do you know how to recognize them in the cockpit? Is it even POSSIBLE to recognize them all in the cockpit? Fuel starvation is one of the leading causes of accidents and is THE most preventable accident cause. The same type of gauges were used in the F-4 Phantoms I flew in my mis-spent youth. One day on a training flight after the external tanks were dry, I started noticing that my fuel quantity seemed to be going down more quickly than Lead's. Too, the gauge was "bouncing around more than normal." After a brief discussion with my back seater we decided we would rather be live sissies than end up walking home or worse, so we told Lead we were heading home. Lead, being a rather arrogant ass, asked us to repeat the diagnosis we had already performed and, in level flight, the gauge seemed to level out just a bit below Lead's reading. Logically, if we both started out with full tanks and there was no leakage, our fuel remaining should be about the same. Lead passed off the fluctuation as a simple gauge problem and said, "let's continue the mission and just keep an eye on it;" however, I told him to take the stick if he wanted to fly my airplane, otherwise we were going home with or without him. He grudgingly "led us back." On the way home, the gauge started falling at an increased pace, so much so that we had Lead drop back twice and look for fuel leaking. None. On short initial the Fuel Low Level light (which was independent from the gauge system) came on - this system was supposed to be "fool proof" and "absolutely reliable" and was supposed to indicate 2200-2300 pounds of fuel remaining (a good 10-12 minutes at reduced power setting). I pitched, throttled back, dropped gear and flaps, turned base, and landed in minimum time with minimum use of throttle. On touchdown I shut down one engine (standard practice); rolled to the end of the runway, turned off and pulled into my hanger (by happenstance the first hanger) all without touching the throttles again and then wrote up the plane for a faulty fuel gauge system. In order to inspect the fuel system gauges, it was necessary to remove the remaining fuel from the aircraft. Full internal fuel on the F-4 was about 12,500 lbs, or about 1900 gallons which represents a bit over an hour of flying time (~180 gallons = 6 minutes; 18 gallons = 0.6 minutes). When they defueled the aircraft, they only got 6 gallons, or less than 20 seconds of fuel remaining. Complacency is the single biggest killer in aircraft accidents. If you trust your newfangled gadgets without verifying, you are an accident statistic waiting to happen - period, and I make no apology for that statement. Now, having said that there ARE legitimate ways to insure there is a "KNOWN QUANTITY" of fuel. My particular Lancair has a header tank, so I can fill that and know I have enough fuel to ferry the aircraft to another airport for cheaper gas. I can (and have) fill a single wing tank, and accept that it will be wing-heavy on takeoff (I lost a gas cap on a cross country, and flew with two tanks rather than be stuck out for a day or more). For those builders who plan ahead ( or a clever person improvising after instruction), tabs can be installed inside the wing fill caps ala' Piper, so that if you "fill to the tabs" you have both a balanced and known quantity of fuel. Some people have carefully calibrated dip sticks to determine exactly how much fuel is in a given tank. All of these are acceptable and reliable practices. However, if you choose to steadfastly maintain that looking at your gauge is a "reliable way to determine your fuel" then all I can say is that when the day comes that I see "fuel starvation" as the cause of your accident, I will tell everyone at your funeral that you were provided with information that could have prevented it and that you knowingly chose to act in a dangerous fashion. Oh, and I'll nominate you for a Darwin Award, too... ;-) Best regards all, Happy New Year, and fly safe! Bill Reister --84c00147-e25c-4134-b1a5-56ad870a4ad0 Content-Type: TEXT/html; charset=utf-8 Content-Transfer-Encoding: 8BIT
I'll give you the "known quantity" definition.  But just because the fuel is in your wing doesn't mean you are 100% sure it's available to burn, right?
 
And a properly functioning, accurately calibrated capacitance probe and digital gage is significantly more accurate than the GA standard fuel gages I had in my 201.
 
A couple things I do to confirm the functionality of my fuel gages is to do the math between the fuel flow reading, fuel tank levels, and how much fuel it takes to fill the tanks when I'm at the pump.  Those little mental math exercises give me a reality check on a regular basis.  For example:
 
If I switch tanks in an hour, my left tank should be down to 30 gallons by then...
 
If I switch tanks now, I should land with about 22 gallons in each tank...
 
It should take about 35 gallons to fill the left tank and 30 gallons to fill the right tank...
 
I completely lost my JPI EDM 900 a few years back, just went black about an hour into a flight.  I landed and got it repaired before flying home.  I knew I had a bunch of fuel on board and how long I'd been flying on the current tank because I keep good ol' tank switching notes on my flight plan sheet on my lap board.  And I do visually check the fuel quantity in my tanks during my preflight, although I can't really tell very accurately how much I have unless the tanks are pretty full.
 
Maybe a paint stick with some Sharpie marks might be a good thing to have for partially fueled flights.
 
Mike Easley
Colorado Springs
 
 
 
 
 
In a message dated 12/27/09 10:51:27 Mountain Standard Time, gt_phantom@hotmail.com writes:
I received two responses to my post; I am responding to both in this post. 

To both Grayhawk and Mike Easley I respectfully submit that you are asking for needless trouble.

If you will refer to my original post, I did not say that "Full" was not the only POSSIBLE "known quantity, but rather that it was the only known quantity for each tank on most Lancairs.  That is a FACTUAL statement, your arguments about the reliability of your respective fuel gauges notwithstanding.

Do you visually confirm that the amount of fuel in each tank matches what the gauge says, and if so, how?  Capacitance gauges, while very accurate today, do have failure modes.  Do you know all of them?  Do you know how to recognize them in the cockpit?  Is it even POSSIBLE to recognize them all in the cockpit? 

Fuel starvation is one of the leading causes of accidents and is THE most preventable accident cause.

The same type of gauges were used in the F-4 Phantoms I flew in my mis-spent youth.  One day on a training flight after the external tanks were dry, I started noticing that my fuel quantity seemed to be going down more quickly than Lead's.  Too, the gauge was "bouncing around more than normal."  After a brief discussion with my back seater we decided we would rather be live sissies than end up walking home or worse, so we told Lead we were heading home.  Lead, being a rather arrogant ass, asked us to repeat the diagnosis we had already performed and, in level flight, the gauge seemed to level out just a bit below Lead's reading.  Logically, if we both started out with full tanks and there was no leakage, our fuel remaining should be about the same.  Lead passed off the fluctuation as a simple gauge problem and said, "let's continue the mission and just keep an eye on it;" however, I told him to take the stick if he wanted to fly my airplane, otherwise we were going home with or without him.  He grudgingly "led us back."

On the way home, the gauge started falling at an increased pace, so much so that we had Lead drop back twice and look for fuel leaking.  None.  On short initial the Fuel Low Level light (which was independent from the gauge system) came on - this system was supposed to be "fool proof" and "absolutely reliable" and was supposed to indicate 2200-2300 pounds of fuel remaining (a good 10-12 minutes at reduced power setting).  I pitched, throttled back, dropped gear and flaps, turned base, and landed in minimum time with minimum use of throttle.  On touchdown I shut down one engine (standard practice); rolled to the end of the runway, turned off and pulled into my hanger (by happenstance the first hanger) all without touching the throttles again and then wrote up the plane for a faulty fuel gauge system.

In order to inspect the fuel system gauges, it was necessary to remove the remaining fuel from the aircraft.  Full internal fuel on the F-4 was about 12,500 lbs, or about 1900 gallons which represents a bit over an hour of flying time (~180 gallons = 6 minutes; 18 gallons = 0.6 minutes).  When they defueled the aircraft, they only got 6 gallons, or less than 20 seconds of fuel remaining.

Complacency is the single biggest killer in aircraft accidents.  If you trust your newfangled gadgets without verifying, you are an accident statistic waiting to happen - period, and I make no apology for that statement.

Now, having said that there ARE legitimate ways to insure there is a "KNOWN QUANTITY" of fuel.  My particular Lancair has a header tank, so I can fill that and know I have enough fuel to ferry the aircraft to another airport for cheaper gas.  I can (and have) fill a single wing tank, and accept that it will be wing-heavy on takeoff (I lost a gas cap on a cross country, and flew with two tanks rather than be stuck out for a day or more).  For those builders who plan ahead ( or a clever person improvising after instruction), tabs can be installed inside t he wing fill caps ala' Piper, so that if you "fill to the tabs" you have both a balanced and known quantity of fuel.  Some people have carefully calibrated dip sticks to determine exactly how much fuel is in a given tank.

All of these are acceptable and reliable practices.  However, if you choose to steadfastly maintain that looking at your gauge is a "reliable way to determine your fuel" then all I can say is that when the day comes that I see "fuel starvation" as the cause of your accident, I will tell everyone at your funeral that you were provided with information that could have prevented it and that you knowingly chose to act in a dangerous fashion.  Oh, and I'll nominate you for a Darwin Award, too...  ;-)

Best regards all, Happy New Year, and fly safe!

Bill Reister
--84c00147-e25c-4134-b1a5-56ad870a4ad0--