Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanks

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Original Posted By: "AircamperN11MS"
Hello good Piet-ple,Hope the sun was shining where you live. It was sure shining in Seattle the pastfew days...! [Rain for the next week however ]Mike from "ready Weld" made another visit and performed more of his craftsmanshipmagic. FYI my axle was moved 3 1/2" forward - to move the CG of the plane forward andmake the plane less likely to nose-over. (Hey, wasn't that topic discussed onthis message board recently...??) THANK YOU ALL for bringing that informationup for discussion.THE FUSELAGE FRAME IS NOT YET COMPLETE - AS I WILL BE ADDING AN ADDITIONAL CROSS-PIECEBETWEEN THE WING STRUTS. (Several owners have had the cross piece failin compression - so this additional structure NEEDS TO BE ADDED in order to preventthis situation.) I had cut the cross-piece tubing but since Mike had alreadyput in almost 12 hours we decided to weld them in next time.........I tried to take photos from angles that would be helpful.Please note that I have not yet completed or flown this plane so do not take anyof this info as proven...(!)Hope all of you are enjoying YOUR Pietenpol adventures/journeys...!!Jake--------Jake Schultz - curator,Newport Way Air Museum (OK, it's just my home)Read this topic online here:http://forums.matronics.com/viewtopic.p ... ttachments: http://forums.matronics.com//files/lg_1 ... ___Subject: Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanksvs. n

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Original Posted By: "jarheadpilot82"
I have a C-85 with a nose and center section tank. 10 in the nose and 12.5 in thecenter section. The carb on the cont engines are the lowest point of the engine.I have 3/8 fueline and the bottom of my nose tank is about 14 inches abovethe floorboards. This arrangement has worked very well on my plane for 42 yearsas well as J3 cubs. The pressure is not as important as the fuel flow. Putyour plane at what you believe is maximum climb angle and do a timed measurefuel rate test. My plane can burn as much as 5.8 gallons per hour. Based on thatnumber you will want to see a fuel delivery rate at 8.7 GPH. That is 1.5 timesthe 5.8 GPH I can burn. Good luck. You should not have any issues.--------Scott LiefeldFlying N11MS since March 1972Steel TubeC-85-12Wire WheelsBrodhead in 1996Read this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanksvs. n

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Original Posted By: "AircamperN11MS"
Mike,Thanks for bringing this up. I don't consider it as bringing up outdated ideasas much as a discussion of risk management. And discussing risk management isnever a bad thing. I have no dog in this hunt as I have yet to decide on fueltank position. I lean toward the Center Section tank, but am open to either location.So here are my questions for people smarter than I to answer-1. Maybe Jack or Ryan can chime in here since it is a CG question. How much movementof the CG would occur with a 200 pound pilot (I know I am not FAA-sized)in the "average" Pietenpol (yes, I know there is no such creature, but you knowwhat I am asking), if there was a 17 gallon fuel tank in the normal nose tanklocation. What would the change be from full (~17 gallons) to reserve (say,3-4 gallons remaining) to completely empty? I realize the center section tankhas much less effect on CG.My point in asking the question is this. In terms of risk management, how manyguys have had incidents involving takeoff or landing out of CG range, as opposedto guys that have landed and the center section gave way? are we creating onerisk management issue (flying out of CG range) by trying to prevent anotherone (the chance of fuel leak/spill in the event of a crash)?2. This is a tough one to ask, but I will ask it. Kevin Purtee is the only guyI know personally that has had an accident in his Pietenpol. We all have heardhis story, and I appreciate his sharing. I would ask him to share one more time.Kevin, do you think that your accident would have had any better or worseoutcome had you had a nose tank instead of a wing tank? What tank are you buildingthis time? Thanks for sharing. I really appreciate it.3. We have had quite a discussion lately on the wisdom of braided fuel lines overhard lines from the center section, so let me add one more thought for discussionof risk management. What about adding breakaway fuel fittings between thecenter section tank and the braided fuel line that would shutoff in the eventthe lines tore away in an accident? Race cars have them. We had them on ourhelicopters when I was in the Marine Corps. Anyone want to chime in on the useof such fittings? Don't tell me they are too expensive as , most likely, onlyone or two would be needed.4. Does anyone know which tank Mr. Pietenpol flew with most often? Just curious.--------Semper Fi,Terry HandAthens, GAUSMC, USMCR, ATPBVD DVD PDQ BBQRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanksvs. n

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Original Posted By: "jarheadpilot82"
Terry, I forgot to mention that my engine gets 100% of its fuel from the nose tank. Whenon a cross country flight I use the center section for the additional fuel.As I burn the fuel from the nose, I refill it from the center section tank througha shut off valve. Just like many other airplanes do.Yes there is a large change in cg if running only a nose tank. I try to keep mynose tank as fuel as I can by draining the CS into it. I weigh 225lbs. I do havea different wing but my cg range is nearly the same as the Piet wing. Thewing tank certainly helps with cg management. My cabains are verticle and I havethe long fuse.As far as which tank is safer??? I guess it would depend on how you crash it andif there is a passenger on board. You could get super crazy and build your tanklike a race car with foam inside. Just saying. You will need to decide whatrisks you are willing to take. I would build mine the same way again.Cheers,--------Scott LiefeldFlying N11MS since March 1972Steel TubeC-85-12Wire WheelsBrodhead in 1996Read this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanksvs. n

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Original Posted By: "Chris"
Good info, Scott. Thanks!--------Semper Fi,Terry HandAthens, GAUSMC, USMCR, ATPBVD DVD PDQ BBQRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________

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Original Posted By: "jarheadpilot82"
Chris,You are absolutely right. William is the first guy I know that had an accidentin his Pietenpol. Kevin is the second.My point was that Kevin is rebuilding his aircraft, so I was wondering what histhoughts were in the rebuild - what, if any changes he would make in the areaof his fuel tank. Did he feel it made any difference as t the cause or outcome.Or none at all.I have read William's postings about fuel lines and cabanes. In fact, I put a linkon this forum right after he wrote those two postings, as I thought they hadvalue for all of us Pietenpol builders and flyers alike.Thanks for reminding me.--------Semper Fi,Terry HandAthens, GAUSMC, USMCR, ATPBVD DVD PDQ BBQRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanksvs. n

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Original Posted By: Brian Kenney
Jack,Thanks for doing the leg work with the spreadsheet. I was hoping you would, sothat people who have not downloaded it, wold still get the info. Thanks.My point of the questions is exactly as you put it. I am not convinced that eitheris better than the other. They both have their risk management issues. I thinkthat the point should be this - make your decision based on an informed analysis,and not because one looks better than the other, or some other less informedreason.--------Semper Fi,Terry HandAthens, GAUSMC, USMCR, ATPBVD DVD PDQ BBQRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________

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Original Posted By: "tools"
etenpol-list(at)matronics.com>Subject: Pietenpol-List: what is reliable?http://www.eaa.org/news/2010/homebuilts ... nttaja.pdf Terry=97see page 6 which compares factory built engine failures to homebuilt engine failures then you decide which ismore reliable. You=92re a smart guy with 2 jobs and lots of time to read all this stuff so I won=92t take time to explain it.and also=85.Terry Hand writes:Mike,I know Mr. Pietenpol (I never knew him, so I respectfully call him Mr. Pietenpol) didn't use the word risk management as nobody did most likely in the 1930s. However I am sure he did use the word safe. I think he would be happy that people were talking about methods to build a "safer" airplane. So I don't think he would spit nickels over the idea of building safe airplanes, and talking about building safe airplanes.Well Terry you might read a lot but you completely misread what I wrote and misquoted me. What I said Bernie would spit nickelsabout is =91this kind of lingo=92 not building safe airplanes. See below. You=92d make a great journalist!Bernie would have spit nickels hearing this kind of ling.________________________________This e-mail message (including any attachments) is for the sole use ofthe intended recipient(s) and may contain confidential and privilegedinformation. If the reader of this message is not the intendedrecipient, you are hereby notified that any dissemination, distributionor copying of this message (including any attachments) is strictlyprohibited.If you have received this message in error, please contactthe sender by reply e-mail message and destroy all copies of theoriginal message (including attachments).________________________________________________________________________________Subject: Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanksvs. n

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Original Posted By: "taildrags"
Jake;Would you mind pointing out where this additional cross-piece will be added? Iguess I must have missed hearing about where compression failures may have occurredin a spot related to this cross-piece, and I can't visualize it from thenarrative that you provided. Thanks.--------Oscar ZunigaMedford, ORAir Camper NX41CC "Scout"A75 powerRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanksvs. n

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Original Posted By: "taildrags"
Terry: I'll tackle your Question No. 1 by plugging your numbers into the Excelspreadsheet that documents my W&B on 41CC, which I also sent to William shortlyafter a very competent EAA Tech Counselor, his experienced assistant, and Iconducted the W&B on race car scales and I documented it in my Excel spreadsheet(which cannot lie, you understand ;o). I believe 41CC was included in William'ssurvey of the geometries, weights, and axle locations of various Air Campersand variants thereof, which survey is presently being discussed and is makingthe rounds.You said to use a 200# pilot and to check the CG shift from 17 gallons in the nosetank down to about 3 gallons remaining in the tank. In my 633 lb. (empty)airplane in the given configuration, the CG shifts 2.3" from 19.1" to 21.4" aftof datum (out of the aft limit). This shift will be the same for any aircraftsince it represents a moment that is the result of a mass times a distance.The important thing, and Jack brought it out, is that in the wing centersectionthe weight changes with fuel burn but it's located essentially on the CGso nothing shifts. In the nose, the weight of the fuel is "hanging" out thereon a moment arm, so as the weight changes, so does the moment. The poor pilot,sitting out there on the other end of the teeter-totter, has no way to moveforward (or shed weight) to balance the lightening load of fuel, so the CG comescreeping aft to get him as punishment for drinking all that beer and eatingall that ice cream while watching TV at night ;o)*FULL DISCLOSURE; TRUTH IN ADVERTISING; ONE PERSON'S OBSERVATION ONLY; USE AT YOUROWN RISK; MAY BE TOTAL B.S. AND UNSAFE*: my airplane has flown in the latterconfiguration on many occasions and the handling was not reported as beingsquirrelly, uncomfortable, unstable, or uncontrollable. On several of those occasions,the pilot was an experienced test pilot, so it may be that his tolerancefor what constitutes "controllability" may be broader than that of the averagerecreational pilot. I am not sanctioning such operation though.--------Oscar ZunigaMedford, ORAir Camper NX41CC "Scout"A75 powerRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanksvs. n

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Original Posted By: "jarheadpilot82"
Airlion: I forgot to address your original question in this thread, but I willecho what was suggested. It's not so much the head of the fuel tank height abovethe carb as it is the fuel flow that you get. You can have a wing centersectiontank several feet above the carb float bowl, but if you use small diameterfuel tubing and a lot of fittings, the fuel flow may still be inadequate.1 ft. of water (static head) = 0.433 psi. This is one of the unbending mathematicallaws that William alluded to. It won't change, as long as Earth's gravitydoesn't. My Stromberg carb was designed for "gravity feed", less than 2 psifuel pressure, or about 4-1/2 ft of head. If you assume that pipe frictionand fittings add roughly 50% to the total head, that means about 3 feet of "gravity"head (elevation)... pretty much the height of a wing tank above a carb.Any more than that pretty much means that you have a "pressurized" system...a fuel pump. Some of the little electric Facet pumps can develop as much as15 psi... definitely a "pressurized" system. So if your system has a nose tank"down low", use good sized fuel lines and minimal fittings. If your tank is"up high", you have the luxury of adding some bends and fittings, and maybe usingslightly smaller tubing, but you're still better off if you keep the tubingsize generous and limit the sharp offset bends and fittings.I won't say what Tony Bingelis recommends for fuel tubing size.--------Oscar ZunigaMedford, ORAir Camper NX41CC "Scout"A75 powerRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanksvs. n

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Original Posted By: "jarheadpilot82"
Oscar,Thanks for the input. Your clear explanation was the reason for my question. Itsounds like running your nose tank low puts the non-standard weighing guy likeme in an aft CG condition that may put the aircraft beyond the recommended aftCG limit. I also get it that you have flown in that regime with little to noconsequence. But my question still boils down to risk management. Are we trading one risk (fuelin the center section, a potential risk in the event of a crash which onehopes never happens) for another risk (nose tank which has the capacity to affectevery flight, but definitely affects longer flights with greater fuel burn).That is not an area that in which I would want to fly on a regular basis.The nice thing about your long, clear explanation is that a beginning builder canwrite in and post this same question a year from now and someone can answerback, "Look it up. It is in the archives" [Wink]--------Semper Fi,Terry HandAthens, GAUSMC, USMCR, ATPBVD DVD PDQ BBQRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Steel-tube fuselage update - landing gear welded

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Original Posted By: "jarheadpilot82"
Mike,First of all, sarcasm is in the eye of the beholder. It usually works best whenspeaking with people who know your normal demeanor and attitude. I did not getthe sarcasm, and I am sure that I am not alone.Long and laborious posts with multiple web links is a problem? Then none of usshould point people toward westcoastpiet.com or any builders website. The truthis that I have all the time in the world to research construction practicesand design issues if it means I build a better airplane. I will take the time.I work 2 jobs, Mike, and I read a lot. It just means I don't watch Dancing WithThe Stars or Duck Dynasty.I think that you sell builders short by assuming that reading and studying as theybuild is just "too much". I am not trying to over complicate things, but Iam trying to research as much as I can. This is a first time build for me, andI don't want it to be my last. If writing a long post about safe constructionpractices or risk management turns people away from building a Pietenpol, thenthey did not need to be building one anyway.Fun can be had and still pass along good information. Give builders some credit,and let them decide to read or not to read.Gonna close, Mike, I am headed to the shop to work on my empennage. That is afterstudying and reading for quite a while yesterday so as to, hopefully avoidmistakes in building.--------Semper Fi,Terry HandAthens, GAUSMC, USMCR, ATPBVD DVD PDQ BBQRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanksvs. n

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Original Posted By: Kip and Beth Gardner
Brian,I am not getting your logic-"Your weight has nothing to do with it. You simply don't fly if there is an aftCG and having the fuel in the wing just makes the problem worse."Fuel in the wing makes it worse? How is that? Fuel in the wing sits closer to theCG than fuel in the nose, and the burn off affects CG less, not more the closerit is to the aircraft's CG."Running out of fuel (or nearly running out of fuel) in a nose tank versus thesame in a wing tank (or nearly running out of fuel) cannot make the situationworse. If the fuel is gone it is gone. The difference that in a nose tank is thatany fuel moves the CG forward at everything but empty. Since no one can flyon empty it is always better in the nose than in the wing and the amount ofweight added to the nose, the length of the engine mount or the amount the wingis moved back is less and on average the cg is more forward. There is also the15lbs or more of the tank weight itself that is helpingthe aft cg problem allthey time. The 10 lbs (or whatever you consider that to be) of reserve fuelthat no one ever uses is also helping. "Brian, I am not worried about the fuel that is left in the nose tank. I am worriedabout the fuel that burned off that was, at one time, forward of the CG thatwas balancing against my fat butt sitting behind the CG. Once that fuel hasburned off, there is less weight to counteract my fat butt, so the CG moves aft.Check your aerodynamics and design books. I just don't want to move it sofar aft, that the airplane is aft of the safe aft CG. That can be mitigated inthe construction phase by adjustment of the wing location, and all I am sayingis that that issue should be dealt with in the build. Nobody should fly an airplaneoutside of the CG range. Will the airplane fly? Yes. Are your optionslessened when you do? Absolutely. "If you weigh more and it is your airplane then it is more important that the fuelis forward."It is most important that the CG is balanced, and the aircraft is flown in theproper CG range.--------Semper Fi,Terry HandAthens, GAUSMC, USMCR, ATPBVD DVD PDQ BBQRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________

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Original Posted By: "jarheadpilot82"
Both the MD 11 and Airbus A330 put fuel in the VERT STAB to help CG issues! In the A330, we just get occasional messages as to what it's doing... nice howit keeps us in the loop...GeeshRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanksvs. n

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Original Posted By: Michael Perez
Mike,Ryan explained it much better than I, so I will simply say, "Yeah. What he said".--------Semper Fi,Terry HandAthens, GAUSMC, USMCR, ATPBVD DVD PDQ BBQRead this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Tue, 25 Mar 2014 09:22:49 -0700 (PDT)

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Original Posted By: "tools"
Terry - To answer your specific question to me: I'm using a wing tank again. 16gallons this time. A fuselage tank sits in the lap of the passenger. In myaccident, a fuselage tank would have resulted in more fuel nearer to me afterimpact than was the case with the wing tank. Had there been a fire I would'velikely died in either scenario. The fuel spill situation was not good afterthe crash, but it was better than if I'd had a fuselage tank.--------Kevin "Axel" PurteeRebuilding NX899KPAustin/San Marcos, TXRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanksvs. n

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Original Posted By: "Cuy, Michael D. (GRC-RXD0)[Vantage Partners, LLC]"
Closer to that than you may like to realize! Seriously. We can't transfer itwillingly, but it can. Just weird. I mean, talk about excess complexity, wow. Of course we're never taught how thething decides whether it needs to move fuel around for CG reasons. Computedusing how much trim is actually being used vs what should be being used basedon flight testing or something I imagine. Isn't like we can mess up the system, because like my Piet, it doesn't even HAVEa trim button!Read this topic online here:http://forums.matronics.com/viewtopic.p ... __________

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Original Posted By: "taildrags"
I'll summarize it for you. Auto engine conversions have less internal failures,but more ignition system, cooling and gear reduction failures.At that level of specificity, it's qualitative not quanitative.Read this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanksvs. n

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Original Posted By: "jarheadpilot82"
I must apologize for posting erroneous information. The same mass acting on thesame moment arm will produce the same moment on any airplane, but it will NOTresult in the same shift in the CG on every airplane. Consider the extremes:my 16 gallon fuel tank on a moment arm a couple of feet long will produce acertain moment and will result in a shift of my CG by a certain amount (coupleof inches). If I place that same fuel tank the same distance away from the CGof a Boeing 777, the CG will not shift perceptibly. If I place that same fueltank the same distance away from the CG of a child's balsa glider... well,you get the idea. You have to calc it for YOUR airplane to determine how muchthe CG will shift as you burn fuel off.I would also encourage anyone who does a W&B on their aircraft to use the wingleading edge as the datum. The reason that I've heard most often for using theface of the prop hub is so that all of the moments are positive and the mathis simplified since there are no negative numbers to deal with. Using the firewallmay make things easier to measure since the firewall is big, flat, and convenient.However, you still need to drop a line from the leading edge to referenceit in the calculations, so why not use the LE?[Abstract thought: using only positive numbers means you throw away almost HALFthe entire universe of numbers just because they are negative. It sounds likediscrimination to me, and a waste of good numbers.]--------Oscar ZunigaMedford, ORAir Camper NX41CC "Scout"A75 powerRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: long to read!

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Original Posted By: "Boatright, Jeffrey"
Been working on the horizontal stab today. Got it glued up on the jig. Glad mycasein glue, I mean T88, works in these temperatures in Georgia.--------Semper Fi,Terry HandAthens, GAUSMC, USMCR, ATPBVD DVD PDQ BBQRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________

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Original Posted By: , "LLC]" >
Weeeelllll, I'm not sure about the interpretation of those data, not because they are wrong and not because you or Ron Wanttaja are wrong. It's just not clear to me that the data available from FAA speak directly to engine failures per se versus what I think of as "systems failures" that directly impinge on engine reliability/performance.Of the engine failures at 2GA9 for which I have direct knowledge, two were Continental O-300s with stuck valves, one that resulted in short final through the pine trees (literally) and the other with an off-field landing (nobody hurt in either one). Another was a Continental C-85 with stuck valve that resulted in a mid-field 'lawn dart' landing with substantial airframe damage and minor injury to pilot. A fourth was a Lycoming IO-360 that holed a piston and resulted in a long glide that ended with a near-perfect outcome (just made the field). So, all four of those were certified engines, all four had true engine failures. Of the experimentals, one went down off-field due to improper induction/fuel system design. Another was a Jabiru 3300 that blew a hole in the oil pump cover. The final was a 2-stroke that crashed on field due to the carb falling off the engine (!), killing the pilot right in front of his family. So, only one of the three experimental engines itself failed. I realize that many anecdotes don't make data, but these examples illustrate the point that what gets termed "engine failure" may not be failure of the engine itself, but rather a failure to provide to the engine that which keeps it running: fuel, spark, or air.--Jeffrey H. Boatright, PhD, FARVOAssociate Professor of OphthalmologyEmory University School of Medicine

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Original Posted By: larharris2 Harris
Abstractly speaking,Maybe more than half? Don't imaginary numbers come the square roots of negatives?Just sayin'Read this topic online here:http://forums.matronics.com/viewtopic.p ... __________

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Original Posted By: "aerocarjake"
Good discussion thread on Weight and Balance. I have just received my package from Doc Mosher with WWs articles. Well documented info on CG and axle location. Keeping the CG location in mind as I build will have a high priority. I have much more to study and learn. The CG spreadsheets recently posted are also valuable tools.New question for some of you who have finished and flown your plane regarding the total weight of the plane. Like everyone=2C I want to be careful of adding unnecessary weight as I build. So far I am following the plans carefully. But like everyone=2C I am sure=2C I have some personal customizations in the back of my mind.WWs articles document specific data from individual planes. I pulled a handful of them to examine more closely regarding Empty Weight (EW) - long/short fuselage=2C A65/Corvair engines. The lightest weight airplane I studied was 590lb=2C the heaviest 842lb. Subtracting a 'standard' engine weight from the EW yielded some interesting information. In most cases=2C regardless of the engine type or fuse. length=2C the weight of 'everything else' came out to about 410-415lb. In only 2 cases I examined was there a great difference - one was 581lb and the other 617lb. Not just over=2C but WAY over the others.Here's the question: What in the world do some builders add to their planes that takes a 400 lb plane to over 600 lb??OK. Some extra instrumentation=2C tailwheel vs the original tailskid=2C brakes system=2C extra fuel tank=2C etc. But 200lb worth? What do I need to look out for?Thanks for the replies.Lorenzo ________________________________________________________________________________Subject: Pietenpol-List: Re: Steel-tube fuselage update - landing gear welded

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Original Posted By: "aviken"
Hello good Piet-ple,Terry, I plan to uses springs.Regarding the "cross-member" that has had some failures, see the RED tube in theattached image. I plan to add a second tube next to the red tube. This second tube will be 0.75"diameter with 0.065" wall thickness. I am going to have it welded about aninch away form the existing tube. This is less than the ideal solution which wouldbe to use a MUCH stronger tube in that location in the first place. What at least three owners have found is that the RED tube is an un-supported two-foottube which collapses in compression during a hard landing. See the additionalattached drawing which shows that in a hard landing the inertia of thewings drives a force down the struts to the landing gear fitting - while at thesame time a force is driven up through the landing gear struts to that samefitting. These forces compress the cross-member and with it "per plans" (onlya 0.035" 5/8" tube) it cannot take the load and the un-supported two foot memberbuckles. This also buckled the sides in a couple inches and ripped up thefloorboards.If I was to do this from scratch I would use a MUCH thicker wall 0.075" diametertube instead of "sistering" another tube alongside the first one, but my clusterjoints are already welded and it should be easier at this time to simplyadd another tube rather than cut up my completed cluster joint.Although, there have been no failures (that I am aware of) in the AFT landing gear(green) cross member location (it is supported mid-span by the "vee" brace),I plan to add another tube there as well.Hope this helps.....Jake--------Jake Schultz - curator,Newport Way Air Museum (OK, it's just my home)Read this topic online here:http://forums.matronics.com/viewtopic.p ... ttachments: http://forums.matronics.com//files/cros ... ___Subject: Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanksvs. n

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Original Posted By: "Boatright, Jeffrey"
I am a new guy so to speak so my opinion probably won't mean much. But here I go.I'm building my piet with the center section tank like the plans call for.If I wanted more endurance I would add a little header tank, but I don't thinkI want it. As far as safety goes , I feel just as safe with a wing tank overmy head, as a nose tank sitting over the passengers legs. Many years agowhen piper entered the crop-duster business with the Pawnee, they built them witha nose tank sitting right behind the engine made of fiberglass no less. I'vemet a few of the guys that flew them and not a few have horrible burn scarson their faces. The first thing that happened at a crash, which is not infrequentin a cropduster, was that the fuel tank was crushed between the chemicalhopper and the engine and a fire. Piper learned after awhile and started buildingthem with wing tanks. Now I admit they were a low wing aircraft so thelocation was lower and along side the cockpit but not as many caught fire. Maybe the center section location is not the safest place for fuel but unlessyou plan on building tip tanks I think it is just as safe as the nose. That ismy two cents worth.And I love all you guys, Well maybe love is not the right word.Read this topic online here:http://forums.matronics.com/viewtopic.p ... __________

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Original Posted By: "jarheadpilot82"
Trouble-maker...--Jeffrey H. Boatright, PhD, FARVOAssociate Professor of OphthalmologyEmory University School of MedicineOn 3/25/14 5:01 PM, "jarheadpilot82" wrote:>>>Been working on the horizontal stab today. Got it glued up on the jig.>Glad my casein glue, I mean T88, works in these temperatures in>Georgia.>>-------->Semper Fi,>>Terry Hand>Athens, GA>>USMC, USMCR, ATP>BVD DVD PDQ BBQ>>>Read this topic online here:>>http://forums.matronics.com/viewtopic.p ... ______This e-mail message (including any attachments) is for the sole use ofthe intended recipient(s) and may contain confidential and privilegedinformation. If the reader of this message is not the intendedrecipient, you are hereby notified that any dissemination, distributionor copying of this message (including any attachments) is strictlyprohibited.If you have received this message in error, please contactthe sender by reply e-mail message and destroy all copies of theoriginal message (including attachments).________________________________________________________________________________Subject: Pietenpol-List: Re: long to read!

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Original Posted By: "Jack Phillips"
If you mean me, Jeff, I have been called much worse. [Laughing]--------Semper Fi,Terry HandAthens, GAUSMC, USMCR, ATPBVD DVD PDQ BBQRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________

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Original Posted By: owner-pietenpol-list-server(at)matronics.com
Lorenzo,My Pietenpol came in at 745 lbs., which was about 80 lbs more than I wasexpecting. I believe most of that extra weight was in the paint that Ichose, PolyFiber's Aerothane polyurethane. It is very heavy, and difficultto paint. I ended up putting several coats on the fuselage before I got adecent finish with a minimum of orange peel. The only way to get it off isto sand it off, and I know I didn't sand all the extra coats off. The wirewheels are also heavy, weighing (with tires and brakes) 25 lbs apiece. Andthe straight axle weighs quite a bit as well. The battery and the avionicsadd a bit but not as much as you'd think, and I was expecting the weightthey added (my original estimate, including the electrical stuff was 660lbs, which would be a decent weight).End result? Mine doesn't climb too well with a heavy load. I limit myselfto carrying passengers weighing no more than 180 lbs. The benefit of thisis, I can limit my passengers to pretty young women for the most part.Simplicate and add lightness!Jack PhillipsNX899JPSmith Mountain Lake, Virginia _____

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Original Posted By: larharris2 Harris
--Jeff BoatrightOn 3/25/14 8:58 PM, "jarheadpilot82" wrote:>If you mean me, Jeff, I have been called much worse. [Laughing]________________________________This e-mail message (including any attachments) is for the sole use ofthe intended recipient(s) and may contain confidential and privilegedinformation. If the reader of this message is not the intendedrecipient, you are hereby notified that any dissemination, distributionor copying of this message (including any attachments) is strictlyprohibited.If you have received this message in error, please contactthe sender by reply e-mail message and destroy all copies of theoriginal message (including attachments).________________________________________________________________________________

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Original Posted By: jack(at)bedfordlandings.com
I like pretty young women . . .

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Original Posted By: jack(at)bedfordlandings.com
Thanks for the input. I'm strongly considering Oratex fabric - so I don't need no stinkin' paint.Lorenzo

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Original Posted By:> jack(at)bedfordlandings.com
Hi Lorenzo I looked at the Oretex website. When checking prices, I became discouraged when all they said was "compared to other finishing systems, the cost of spray guns, compressor setting up a booth...blah blah blah Oretex is comparable to other finishing systems". Please cut to the chase. Here. What does it cost to cover a pietenpol? Anytime a supplier hides behind a bunch of B S , I run the other direction. The concept is interesting, however Thanks GlenSent from my iPhone> On Mar 25, 2014, at 7:14 PM, larharris2 Harris wrote:> > Thanks for the input. I'm strongly considering Oratex fabric - so I don't need no stinkin' paint.> > Lorenzo> >

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Original Posted By: "Clif Dawson"
Lorenzo,I did a little "dumpster diving" on the internet and found a guy's estimate fromBetter Aircraft Fabric for the Oratex 6000 dated September 2013. It shows theprice for the 1800mmX1m material to be $134.87. I think that the Oratex 600is slightly cheaper, but I am not 100% sure on that.Doing the Math, 1800mmX1m equals 1.8 square meters which equal 2.15 square yards,or $62.73 per square yard. The invoice shows the cost of glue tape, etc. butthis is what I come up with for the price of the cloth itself.I have seen this stuff first hand at OSH and I have to say, it is as strong asyou-know-what! They beat on it with a huge hammer, then took heat and pulled outthe divits in the fabric right there in seconds. Really impressive stuff.I am strongly considering the use of Oratex for the same reasons you mentioned- weight savings, strength, ease of use, and savings on the cost of painting equipment.I will tell you this, though. If you want a glossy finish, then youshould move on to another covering. I would not call it dull, but it definitelyis not glossy. Works for me, but you may want a different look.--------Semper Fi,Terry HandAthens, GAUSMC, USMCR, ATPBVD DVD PDQ BBQRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________

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Original Posted By: "jarheadpilot82"
Cliff,You ask, "Doesn't everything below it act like a pendulum? The short answer is NO, however that requires some explanation...In a most properly designed and built airplane - the designer sets CG so the planeis slightly nose heavy, which requires an equal and opposite tail down forcein flight. Now on the surface this may appear to be a pendulum, but in fact,its quite different. The purpose of nose heavy, coupled with tail down force is what gives us pitchstability. In other words, the plane will tend to stabilize itself in flightwhen you take your hands off the stick -assuming, of course, that you've trimmedthe plane for whatever pitch attitude you need.What is somewhat bothersome is that many on the list have indicated that the elevatoron a Piet "droops" during flight, when in fact, the elevator should beslightly up, in which case it's providing the tail down force. Perhaps the horizontal stabilizer on the Piet is - HERESY COMING - improperly designed,but satisfactory. If the angle of incidence of the stab were changedsomewhat, this condition would be corrected...Personally, I'd like for Jack Phillips and a few of the others to comment on thedrooping issue, as I'd like to make sure the plane I build is flying "correctly."I KNOW, I KNOW, I KNOW, BUILD IT PER THE PLANS, AND IT WILL FLY.... that stilldoesn't satisfy the Mechanical Engineer I am.... just sayin.--------Tom KreinerRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: It's FINALLY a hangar...

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Original Posted By: "tkreiner"
Tools,Share with everybody how > expensive that big hangar is, and how you did it. I think that it would encourage peoplewith maybe ideas of their own.P.S. She looks like you gave her a bath from when I was at Toolstock. It IS goodto have Scott around!--------Semper Fi,Terry HandAthens, GAUSMC, USMCR, ATPBVD DVD PDQ BBQRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanksvs. n

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Original Posted By: "tkreiner"
Cliff,You ask, "Doesn't everything below it act like a pendulum? The short answer is NO, however that requires some explanation...In a most properly designed and built airplane - the designer sets CG so the planeis slightly nose heavy, which requires an equal and opposite tail down forcein flight. Now on the surface this may appear to be a pendulum, but in fact,its quite different. The purpose of nose heavy, coupled with tail down force is what gives us pitchstability. In other words, the plane will tend to stabilize itself in flightwhen you take your hands off the stick -assuming, of course, that you've trimmedthe plane for whatever pitch attitude you need.What is somewhat bothersome is that many on the list have indicated that the elevatoron a Piet "droops" during flight, when in fact, the elevator should beslightly up, in which case it's providing the tail down force. Perhaps the horizontal stabilizer on the Piet is - HERESY COMING - improperly designed,but satisfactory. If the angle of incidence of the stab were changedsomewhat, this condition would be corrected...Personally, I'd like for Jack Phillips and a few of the others to comment on thedrooping issue, as I'd like to make sure the plane I build is flying "correctly."I KNOW, I KNOW, I KNOW, BUILD IT PER THE PLANS, AND IT WILL FLY.... that stilldoesn't satisfy the Mechanical Engineer I am.... just sayin.--------Tom KreinerRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanksvs. n

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Original Posted By: "jarheadpilot82"
Cliff,In response to your question, "Doesn't everything below it act like a pendulum? The short answer is NO, that said, some explanation is required...In a properly designed and built airplane - the designer sets the CG so that theplane is slightly nose heavy, which, in flight, requires an equal and oppositetail down force. Now on the surface this may appear to be a pendulum, butin fact, its quite different. The purpose of nose heavy, coupled with tail down force is what gives us pitchstability. In other words, the plane will tend to stabilize itself in flightwhen you take your hands off the stick - and return to whatever pitch it's trimmedfor, assuming, of course, that you've trimmed the plane for a given pitchattitude, i.e., climb, cruise, descent.What is somewhat bothersome is that many on the list have indicated that the elevatoron a Piet "droops" during cruise flight, when in fact, the elevator shouldbe slightly up, in order to provide the tail down force. Perhaps the horizontal stabilizer on the Piet is - HERESY COMING - improperly designed,but satisfactory. If the angle of incidence of the stab were changedsomewhat, this condition might be corrected...Personally, I'd like for Jack Phillips and a few of the others to comment on thedrooping issue, as I'd like to make sure the plane I build is flying "correctly."I KNOW, I KNOW, I KNOW, BUILD IT PER THE PLANS, AND IT WILL FLY.... that stilldoesn't satisfy the Mechanical Engineer I am.... just sayin.--------Tom KreinerRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Speaking of outdated stuff? Center section fuel tanksvs. n

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Original Posted By: Brian Kenney
My theory of the elevator droop is it could be an optical illusion. The outboardline from the elevator and horizontal stabilizer is bent because of the leadingedge of the horizontal stabilizer not having the same span as the rest ofthe tail. I had this discussion and wanted to do some testing at Brodhead last year, butbecause of lack of time I was unable. I propose those who could, prior to Brodhead, set, their elevators in a faired(neutral) position and and somehow temporarily make a mark on their torque tubeand the cable just above. Then go fly and compare in cruise flight if the marks are aligned yet. If not,make another mark to show the difference. Also while the tail is faired neutral on the ground, sit in the cockpit and lookover your shoulder and look or take a picture of the tail and let us know whatit looks like. Take pictures in slightly up and down elevator position. This is a great exercise not only to prove my theory right/wrong, but also likeTom said, the tail should always be creating downforce while flying and if elevatorsare drooping, the horizontal stab might need some shimming and re-rigging.My planes not flying and I'm definitely not an Opthamolagist, he'll I don't eventhink I can spell.--------Curt MerdanFlower Mound, TXRead this topic online here:http://forums.matronics.com/viewtopic.p ... ttachments: http://forums.matronics.com//files/imag ... __________

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Original Posted By: "Jack Phillips"
Jack,I concur, it appears to be an optical illusion... But if that's the case, why does Dick N give a spiel on drooping at Brodhead?--------Tom KreinerRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________

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Original Posted By: larharris2 Harris
=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0ALorenzo=2C=0A=0A =0A=0AMy Pietenpol came in at 745 lbs.=2C which=0Awas about 80 lbs more than I was expecting. I believe most of that extra=0Aweight was in the paint that I chose=2C PolyFiber=92s Aerothane=0Apolyurethane. It is very heavy=2C and difficult to paint. I ended up=0Aputting several coats on the fuselage before I got a decent finish with a=0Aminimum of orange peel. The only way to get it off is to sand it off=2C and=0AI know I didn=92t sand all the extra coats off. The wire wheels are=0Aalso heavy=2C weighing (with tires and brakes) 25 lbs apiece. And the straight=0Aaxle weighs quite a bit as well. The battery and the avionics add a bit=0Abut not as much as you=92d think=2C and I was expecting the weight they added=0A(my original estimate=2C including the electrical stuff was 660 lbs=2C which would=0Abe a decent weight).=0A=0A =0A=0AEnd result? Mine doesn=92t climb=0Atoo well with a heavy load. I limit myself to carrying passengers=0Aweighing no more than 180 lbs. The benefit of this is=2C I can limit my=0Apassengers to pretty young women for the most part.=0A=0A =0A=0ASimplicate and add lightness!=0A=0A =0A=0AJack Phillips=0A=0ANX899JP=0A=0ASmith Mountain Lake=2C Virginia=0A=0A ________________________________________________________________________________

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Original Posted By: glenschweizer(at)yahoo.com
=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0A=0ALorenzo=2C=0A=0A =0A=0AMy Pietenpol came in at 745 lbs.=2C which=0Awas about 80 lbs more than I was expecting. I believe most of that extra=0Aweight was in the paint that I chose=2C PolyFiber=92s Aerothane=0Apolyurethane. It is very heavy=2C and difficult to paint. I ended up=0Aputting several coats on the fuselage before I got a decent finish with a=0Aminimum of orange peel. The only way to get it off is to sand it off=2C and=0AI know I didn=92t sand all the extra coats off. The wire wheels are=0Aalso heavy=2C weighing (with tires and brakes) 25 lbs apiece. And the straight=0Aaxle weighs quite a bit as well. The battery and the avionics add a bit=0Abut not as much as you=92d think=2C and I was expecting the weight they added=0A(my original estimate=2C including the electrical stuff was 660 lbs=2C which would=0Abe a decent weight).=0A=0A =0A=0AEnd result? Mine doesn=92t climb=0Atoo well with a heavy load. I limit myself to carrying passengers=0Aweighing no more than 180 lbs. The benefit of this is=2C I can limit my=0Apassengers to pretty young women for the most part.=0A=0A =0A=0ASimplicate and add lightness!=0A=0A =0A=0AJack Phillips=0A=0ANX899JP=0A=0ASmith Mountain Lake=2C Virginia=0A=0A =0A=0A=0A=0A=0A=0A=0A=0A=0A=0A ________________________________________________________________________________

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Original Posted By: "jarheadpilot82"
> > Lorenzo,> > > > My Pietenpol came in at 745 lbs., which was about 80 lbs more than I was expecting. I believe most of that extra weight was in the paint that I chose, PolyFiber=99s Aerothane polyurethane. It is very heavy, and difficult to paint. I ended up putting several coats on the fuselage before I got a decent finish with a minimum of orange peel. The only way to get it off is to sand it off, and I know I didn=99t sand all the extra coats off. The wire wheels are also heavy, weighing (with tires and brakes) 25 lbs apiece. And the straight axle weighs quite a bit as well. The battery and the avionics add a bit but not as much as you=99d think, and I was expecting the weight they added (my original estimate, including the electrical stuff was 660 lbs, which would be a decent weight).> > > > End result? Mine doesn=99t climb too well with a heavy load. I limit myself to carrying passengers weighing no more than 180 lbs. The benefit of this is, I can limit my passengers to pretty young women for the most part.> > > > Simplicate and add lightness!> > > > Jack Phillips> > NX899JP> > Smith Mountain Lake, Virginia> > > > > > > 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D> ________________________________________________________________________________Subject: Pietenpol-List: Re: Airplane Weights