---------------------------------------------------------- Kitfox-List Digest Archive --- Total Messages Posted Thu 10/16/08: 14 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 08:12 AM - Re: Aligning the wings (Tom Jones) 2. 08:46 AM - Re: Aligning the wings (Jim Feldmann) 3. 12:16 PM - Note on Ethanol (Rich L) 4. 01:35 PM - Re: Note on Ethanol (Frank Miles) 5. 04:57 PM - Re: Note on Ethanol (Tom Jones) 6. 05:05 PM - Header Tank Venting (SkySteve) 7. 06:05 PM - Re: Header Tank Venting (tc9008@aol.com) 8. 06:05 PM - Re: Header Tank Venting (tc9008@aol.com) 9. 06:10 PM - Re: Note on Ethanol (Rich L) 10. 06:16 PM - Re: Header Tank Venting (Dee Young) 11. 09:24 PM - Re: Re: Note on Ethanol (Paul A. Franz, P.E.) 12. 09:40 PM - Re: Header Tank Venting (Paul A. Franz, P.E.) 13. 10:18 PM - Re: Header Tank Venting (Lowell Fitt) 14. 11:03 PM - Re: Header Tank Venting (Guy Buchanan) ________________________________ Message 1 _____________________________________ Time: 08:12:53 AM PST US Subject: Kitfox-List: Re: Aligning the wings From: "Tom Jones" Jim Feldmann wrote: > I just bought my Kitfox and after I got it home, I discovered that the left wing is straight from root to tip, but the right wing is twisted leading-edge down (washed-out) about 2 degrees. I realize that this was probably done to make it fly level with only the pilot on board, but it is excessive and the plane has a built-in right roll, even flown solo. > > I am also concerned about a possible stall-spin problem from the different angle of attack from one side to the other. > > The Builders Manual that I got with the airplane does not discuss wing alignment. Can anyone tell me what the factory specs are? Should both wings be straight? Both washed-out a degree of so? I don't know whether I should eliminate the excess wash-out in the right wing, or twist in a little washout on the left wing, or both? > > Thanks. > > Jim Feldmann > 1994 Kitfox Speedster/Rotax 912 > Flying Jim, the wings are built upside down on saw horses with the saw horse tops level or parallel in relation to each other. A 1/2" block is placed under the tip end of the front spar to result in the finished wing having 1/2" of washout between the spars per 13 feet. The speedster wing spars are cut after the ribs are attached to achieve an accurate amount of twist. In other words, the speedster wings have the same twist per foot, but a hair less than 1/2" washout from root to tip. -------- Tom Jones Classic IV 503 Rotax, 72 inch Two blade Warp Ellensburg, WA Read this topic online here: http://forums.matronics.com/viewtopic.php?p 9034#209034 ________________________________ Message 2 _____________________________________ Time: 08:46:21 AM PST US Subject: Kitfox-List: Re: Aligning the wings From: "Jim Feldmann" Thanks very much guys. I will re-rig it per those specs and then see what straight and level flight trim looks like. -------- Jim Feldmann, 3rd owner 1994 Kitfox Speedster / 912 Flying Read this topic online here: http://forums.matronics.com/viewtopic.php?p 9041#209041 ________________________________ Message 3 _____________________________________ Time: 12:16:55 PM PST US Subject: Kitfox-List: Note on Ethanol From: "Rich L" This MS Word Document is from the Idaho Aviation Association (IAA). Thought it might be of interest. Rich L Read this topic online here: http://forums.matronics.com/viewtopic.php?p 9063#209063 Attachments: http://forums.matronics.com//files/discussion_of_ethanol_mandates_281.doc ________________________________ Message 4 _____________________________________ Time: 01:35:21 PM PST US From: "Frank Miles" Subject: RE: Kitfox-List: Note on Ethanol Rich, When was this article written? Last year? The date on the top is October 18. Two days from now. If so, a lot has happened since then. As I understand it the Idaho and Washington legislation that was passed regarding ethanol fuel mandated that "91 octane fuel is too made available for aviation and recreational use". I just dare you to find it and no distributor, that I can find, wants to talk about it. Oh yes, I dropped a note to the Idaho Dept. of Aviation about his matter and did not even get the courtesy of a response. Frank Miles Lewiston, Idaho -----Original Message----- From: owner-kitfox-list-server@matronics.com [mailto:owner-kitfox-list-server@matronics.com] On Behalf Of Rich L Sent: Thursday, October 16, 2008 12:16 PM Subject: Kitfox-List: Note on Ethanol This MS Word Document is from the Idaho Aviation Association (IAA). Thought it might be of interest. Rich L Read this topic online here: http://forums.matronics.com/viewtopic.php?p 9063#209063 Attachments: http://forums.matronics.com//files/discussion_of_ethanol_mandates_281.doc ________________________________ Message 5 _____________________________________ Time: 04:57:00 PM PST US Subject: Kitfox-List: Re: Note on Ethanol From: "Tom Jones" For what it's worth. I have been using Union 76 premium 92 octane in Ellensburg, WA. I have been testing for alcohol and as of 10-13 have not found any in 76's premium. I use the EAA recommended water in a jar test. I was using Chevron premium until the alcohol showed up about mid July this year. -------- Tom Jones Classic IV 503 Rotax, 72 inch Two blade Warp Ellensburg, WA Read this topic online here: http://forums.matronics.com/viewtopic.php?p 9098#209098 ________________________________ Message 6 _____________________________________ Time: 05:05:11 PM PST US Subject: Kitfox-List: Header Tank Venting From: "SkySteve" My header tank (located behind the seat) is vented back to both wing tanks via two vent lines (one to each wing tank). I was advised to install a shut off valve in each vent line and to open those vent lines when filling the fuel tanks, then shut the vent valves for flight. It was mentioned that in the past, there were several crashes due to fuel starvation when the wing tanks were full of fuel. Apparently air had mixed with the fuel in the vent lines and vapor lock stopped the fuel flow from the wing tanks to the header tank. The result was when the header tank ran out of fuel the engine stopped due to fuel starvation. Is this true? Should I install shut off valves in each of my two vent lines and close those valves for flight? -------- Steve Wilson Huntsville, UT Kitfox Model 134 - 85DD 912A / 3 Blade Warp Drive Convertible Nosewheel & Tailwheel Read this topic online here: http://forums.matronics.com/viewtopic.php?p 9099#209099 ________________________________ Message 7 _____________________________________ Time: 06:05:54 PM PST US Subject: Re: Kitfox-List: Header Tank Venting From: tc9008@aol.com I have flown a Kitfox IV? 582 since 2004 and have had a problem. Travis -----Original Message----- From: SkySteve Sent: Thu, 16 Oct 2008 8:04 pm Subject: Kitfox-List: Header Tank Venting My header tank (located behind the seat) is vented back to both wing tanks via two vent lines (one to each wing tank). I was advised to install a shut off valve in each vent line and to open those vent lines when filling the fuel tanks, then shut the vent valves for flight. It was mentioned that in the past, there were several crashes due to fuel starvation when the wing tanks were full of fuel. Apparently air had mixed with the fuel in the vent lines and vapor lock stopped the fuel flow from the wing tanks to the header tank. The result was when the header tank ran out of fuel the engine stopped due to fuel starvation. Is this true? Should I install shut off valves in each of my two vent lines and close those valves for flight? -------- Steve Wilson Huntsville, UT Kitfox Model 134 - 85DD 912A / 3 Blade Warp Drive Convertible Nosewheel & Tailwheel Read this topic online here: http://forums.matronics.com/viewtopic.php?p 9099#209099 ________________________________ Message 8 _____________________________________ Time: 06:05:59 PM PST US Subject: Re: Kitfox-List: Header Tank Venting From: tc9008@aol.com I have flown a Kitfox IV? 582 since 2004 and have had a problem. Travis -----Original Message----- From: SkySteve Sent: Thu, 16 Oct 2008 8:04 pm Subject: Kitfox-List: Header Tank Venting My header tank (located behind the seat) is vented back to both wing tanks via two vent lines (one to each wing tank). I was advised to install a shut off valve in each vent line and to open those vent lines when filling the fuel tanks, then shut the vent valves for flight. It was mentioned that in the past, there were several crashes due to fuel starvation when the wing tanks were full of fuel. Apparently air had mixed with the fuel in the vent lines and vapor lock stopped the fuel flow from the wing tanks to the header tank. The result was when the header tank ran out of fuel the engine stopped due to fuel starvation. Is this true? Should I install shut off valves in each of my two vent lines and close those valves for flight? -------- Steve Wilson Huntsville, UT Kitfox Model 134 - 85DD 912A / 3 Blade Warp Drive Convertible Nosewheel & Tailwheel Read this topic online here: http://forums.matronics.com/viewtopic.php?p 9099#209099 ________________________________ Message 9 _____________________________________ Time: 06:10:42 PM PST US Subject: Kitfox-List: Re: Note on Ethanol From: "Rich L" That note just came to me from the IAA. The October 18 is the date of the board meeting where this will be discussed. Some of the information was written up on the latest newsletter on the IAA web site. (www.flyidaho.org). Here are some of the local stations which sell non-contaminated premium fuel: Dykes Exon in Bonners Ferry has a Pacific Pride Pump in back. The Coop in Sandpoint. I saw a list of other stations mostly in southern Idaho . Read this topic online here: http://forums.matronics.com/viewtopic.php?p 9111#209111 ________________________________ Message 10 ____________________________________ Time: 06:16:42 PM PST US From: "Dee Young" Subject: Re: Kitfox-List: Header Tank Venting Steve on my model II I have one vent line that runs from the header tank. I run it up and ported it out thru a butt rib using a check valve. It allows air in but will not let fuel run out. It works very well and have no problems. If you go thru the archives you will find a number of discussions on fuel tanks, venting and porting etc. Dee Young Model II N345DY KFM 112 Do not archive ----- Original Message ----- From: SkySteve To: kitfox-list@matronics.com Sent: Thursday, October 16, 2008 6:04 PM Subject: Kitfox-List: Header Tank Venting > My header tank (located behind the seat) is vented back to both wing tanks via two vent lines (one to each wing tank). I was advised to install a shut off valve in each vent line and to open those vent lines when filling the fuel tanks, then shut the vent valves for flight. It was mentioned that in the past, there were several crashes due to fuel starvation when the wing tanks were full of fuel. Apparently air had mixed with the fuel in the vent lines and vapor lock stopped the fuel flow from the wing tanks to the header tank. The result was when the header tank ran out of fuel the engine stopped due to fuel starvation. Is this true? Should I install shut off valves in each of my two vent lines and close those valves for flight? -------- Steve Wilson Huntsville, UT Kitfox Model 134 - 85DD 912A / 3 Blade Warp Drive Convertible Nosewheel & Tailwheel Read this topic online here: http://forums.matronics.com/viewtopic.php?p 9099#209099 http://www.matronics.com/Navigator?Kitfox-List http://www.matronics.com/contribution ________________________________ Message 11 ____________________________________ Time: 09:24:04 PM PST US Subject: Re: Kitfox-List: Re: Note on Ethanol From: "Paul A. Franz, P.E." On Thu, October 16, 2008 4:56 pm, Tom Jones wrote: > > For what it's worth. I have been using Union 76 premium 92 octane in Ellensburg, WA. > I have been testing for alcohol and as of 10-13 have not found any in 76's premium. I > use the EAA recommended water in a jar test. I was using Chevron premium until the > alcohol showed up about mid July this year. I can verify that Chevron is using 10% Ethanol in Bellevue WA and possibly all of Western Washington. It even says so on the pumps. Chevron and Exxon-Mobil are building Bio-Diesel blending plants in Washington. The Exxon plant in Spokane will be fully operational in December. One thing good is that MTBE is dead. Estimates say E90 costs more and gives a uniform 8% reduction in fuel mileage. It has a lower flash point and higher vapor pressure than gasoline so this is genuine concern with operating altitude even if you've solved the problems with gaskets, seals and corrosion. Pipeline operators are not blending ethanol because they claim the corrosivity of ethanol threatens the integrity of the pipelines. As a result, ethanol is blended at the pipeline delivery points, chiefly Harbor Island in Seattle so it is likely that all gasoline has the 10% blend in Western Washington. -- Paul A. Franz, P.E. PAF Consulting Engineers Office 425.440.9505 Cell 425.241.1618 ________________________________ Message 12 ____________________________________ Time: 09:40:23 PM PST US Subject: Re: Kitfox-List: Header Tank Venting From: "Paul A. Franz, P.E." On Thu, October 16, 2008 5:04 pm, SkySteve wrote: > > My header tank (located behind the seat) is vented back to both wing tanks via two > vent lines (one to each wing tank). I was advised to install a shut off valve in each > vent line and to open those vent lines when filling the fuel tanks, then shut the vent > valves for flight. > > It was mentioned that in the past, there were several crashes due to fuel starvation > when the wing tanks were full of fuel. Apparently air had mixed with the fuel in the > vent lines and vapor lock stopped the fuel flow from the wing tanks to the header > tank. The result was when the header tank ran out of fuel the engine stopped due to > fuel starvation. > > Is this true? Should I install shut off valves in each of my two vent lines and close > those valves for flight? I'd have to see a drawing but that doesn't make sense as I understand the configuration. What will block the vent line is low points or multiple low points such that they act as a trap with fuel in it and air on both sides. It can't siphon and causes hydraulic blockage. As long as the vent line goes up continuously and terminates in an air gap, you should never get a condition where there is hydraulic blockage. -- Paul A. Franz, P.E. PAF Consulting Engineers Office 425.440.9505 Cell 425.241.1618 ________________________________ Message 13 ____________________________________ Time: 10:18:02 PM PST US From: "Lowell Fitt" Subject: Re: Kitfox-List: Header Tank Venting Steve, I don't understand the thinking on the double vent unless it was done to prevent the often seen uneven draining of the wing tanks. This phenomenon has been discussed very often on the list and in one instance in the wilds of Idaho it resulted in a panic stop to check for an obstruction in the fuel lines. After carefully measuring fuel flow from each tank, we were finally able to convince the troubled pilot that the fuel flow was fine and wasn't going to have to put it down over the Sawtooth Mountains because of the uneven fuel use from his wing tanks. Your double vents are a one off design change from the factory configuration. I don't think you will find any instances of full tank fuel starvation proper fuel line routing and with the vents in place and putting valves in the vent lines and closing them in flight is contrary to the current design. Putting valves in the vent lines would conceivably serve to make fuel system maintenance easier, but it is a lot of hardware to simply avoid clamping the lines if maintenence is necessary. Keep in mind, the following service letter should clear up the factory's view on the instances you refer to. http://www.kitfoxaircraft.com/support/service_letters/sl22.htmhttp://www.kitfoxaircraft.com/support/service_letters/sl22.htm The referenced Service Bulletin will continue the factory comments: http://www.kitfoxaircraft.com/support/service_bulletins/sb29.htmKeep It is a fact that lots of us have seen what we believe to be design weaknesses in the factory scheme and have modified according to our own perception of safe, but many of the modifications fly in the face of a fine history of reliability. I had 900 hours on my Model IV when I put it on the ground because of an oil pressure drop due to a blockage of the oil line to the pump - foreign object, and I have three friends who I flew with regularly that each had nearly 1000 hours on Model IVs. All with one vent line to the right wing tank, and all with no hint of fuel flow issues with the factory configuration. Keep in mind that in a fairly steep descent with the aft ported wing tanks, it is possible to unport the tanks if the fuel level is below a certain amount. I found that to be true during the 30 minute descent from 12,000 ft over the Sierras, to my field elevation of 1300 ft. With the factory design, the header tank immediately resumed filling from the wing tanks after reducing the descent for a time. And that was with four gallons remaining in each tank measured on the ground. I was descending at 400 fpm at just below redline on the ASI. My thought is to not close the valves in flight. I am curious about the source of the advice. Lowell ----- Original Message ----- From: "SkySteve" Sent: Thursday, October 16, 2008 5:04 PM Subject: Kitfox-List: Header Tank Venting > > My header tank (located behind the seat) is vented back to both wing tanks > via two vent lines (one to each wing tank). I was advised to install a > shut off valve in each vent line and to open those vent lines when filling > the fuel tanks, then shut the vent valves for flight. > > It was mentioned that in the past, there were several crashes due to fuel > starvation when the wing tanks were full of fuel. Apparently air had > mixed with the fuel in the vent lines and vapor lock stopped the fuel flow > from the wing tanks to the header tank. The result was when the header > tank ran out of fuel the engine stopped due to fuel starvation. > > Is this true? Should I install shut off valves in each of my two vent > lines and close those valves for flight? > > -------- > Steve Wilson > Huntsville, UT > Kitfox Model 134 - 85DD > 912A / 3 Blade Warp Drive > Convertible Nosewheel & Tailwheel > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p 9099#209099 > > > ________________________________ Message 14 ____________________________________ Time: 11:03:10 PM PST US From: Guy Buchanan Subject: Re: Kitfox-List: Header Tank Venting At 05:04 PM 10/16/2008, you wrote: >It was mentioned that in the past, there were several crashes due to >fuel starvation when the wing tanks were full of fuel. Apparently >air had mixed with the fuel in the vent lines and vapor lock stopped >the fuel flow from the wing tanks to the header tank. The result >was when the header tank ran out of fuel the engine stopped due to >fuel starvation. > >Is this true? Should I install shut off valves in each of my two >vent lines and close those valves for flight? Steve, Thanks for asking this question. I have finally convinced myself that this is possible. It's not vapor lock, but if your wing tank fuel feed line were to rise above the wing tank fuel level before travelling to the header tank, and the header was vented to atmosphere, the wing tank would stop feeding. (There would be no way to siphon from the wing tank because the header tank was vented to atmosphere.) Therefore you'd have to block the vent to force fuel to siphon from the wing tank. My system without the vent valve works because my wing tank feed lines run down-hill to the header tank; no siphon is necessary. (I could have a problem on an extremely long, extremely steep descent, because my fuel lines run aft from the wing tanks.) So I guess the answer becomes: either your wing tank fuel lines run down-hill, or you install the valves. Guy Buchanan San Diego, CA K-IV 1200 / 582-C / Warp / 100% done, thanks mostly to Bob Ducar. ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message kitfox-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Kitfox-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/kitfox-list Browse Digests http://www.matronics.com/digest/kitfox-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.