Brodhead Pietenpol Association

Original Posted By: danhelsper(at)aol.com
This is not a simple problem and it is hard to give correct advice and it is the classic example that everything is compromise.The following are variables that effect the gear position. If you are wonder "what the heck: then I will give an example of why some of these are important.VARIABLESthe empty c.g.the loaded c.g.the expected c.g rangethe fuel placementthe maximum weight of the pilot=2C the minimum weight of the pilotthe assumed wing position=2C the final wing positionthe strength of the brakesthe diameter of the wheelsthe total height of the c.g above the ground. WHAT THE VARIABLES EFFECTThe weight on the tail when emptywhether the tail will stay down while empty in a windthe strength of the tail wheel spring and structurethe ability to stop with brakesthe ability to hold the aircraft on run upthe overturn tendency with brakesthe directional stability (ground looping tendency)the tendency for the tail to drop hard on landing (if not three pointed)the tendency to porpoisethe ground handlingwhat the government says about c.g.Here is an example - I will use my example so not to offend anyone.My aircraft has wooden gear=2C motorcycle wheels with brakes =2C and perpendicular cabanes. It is an improved fuselage from the 1933 plans and the stock 1931 wooden gear. The fuel is behind the firewall.I am happy with arrangement but it has limitations and it could easily criticized as wrong=2C but being wrong has some advantages. As built my airplane has the following advantages-the load on the tail is very light and the structure is light helping the aft c.g. tendency - the gear is back in comparison to many giving improved handling and stability on landingthis means the tail is not forcefully driven down if you land hard .-the tail comes up very easily on the take off roll. -it has had thousands of landings over 27 years and it has never been damaged in a landing incident. This aircraft is not squirrelly at allthe large wheels reduce rolling resistance=2C and reduces takeoff distance.- large wheels move the contact point of the wheels in the three point attitude to the rear making it more directional stable.-the fuel in the fuselage reduces the weight transfer back to the tail as the tail drops in comparison to fuel in the wing.My gear position has the following disadvantages-If I had stronger brakes it would be a danger to flip over - I am very happy with my brakes however - they won't hold on a runup buy I don't think that would be a good idea anyway. -my tail is so light when empty that if you lift the tail past horizontal the airplane will fall on its nose - never has=2C but don't lose hold-I operate at and around the aft cg limit. If I were to put weight on the nose to make the recommended c.g. limits for aircraft built in Canada=2C I could not get out of the aircraft as it would fall on its nose. Where I operate the c.g. is as recommended for a Pietenpol and there is not a problem. It may improve the climb performance.-As I age and get heavier the c.g. is getting more aft and adding weight to the nose would make the gear position worse in the rear direction - it is not really a problem and I can have full fuel and a metal prop instead of a wood one. I really added this to show how the pilot max weight effects the setup. -if a very light pilot used my brakes very hard the tail would come up far easierRemember too that many Piets end up with aft cgs and they move the wing back once built. This moves the wheels forward. Best laid plans quickly change. One of my favourite saying is - you can be good or you can be lucky but it is always best to be lucky. ________________________________________________________________________________Subject: Re: Pietenpol-List: Re: CG vs Wheels Location..emergency situation

Original Posted By: Don Emch
Yesterday I got an emergency call from the great T.C. emeritus while wandering on a remote desert path. I hadn't looked at the list in a few days....YIKES! All the oxygen is being sucked out of the room. I am glad it wasn't like this when I was first building. I would have given up, eyes completely glazed over.I though y'all were building an old airplane from a set of old plans.Dan HelsperPuryear, TN-----Original Message-----

Original Posted By: "William Wynne"
I have a couple of welding questions that I hope some of you can help me answer.Here is the situation - a friend of mine in my EAA Chapter has all of his nowpassed grandfather's tools (he was Mechanic at Delta Air Lines for over 35years) My friend is building an RV-10 so he has little use for the welding equipment,so he has offered it to me. I have read some but have no one to reallyguide me on the following questions, so your help is appreciated.1. The tanks have some level of Oxygen and Acetylene in them but the tanks havenot been tested in who knows when (I have not really looked for the last datestamped onto them. Is it safe to use them ntl empty? Or should I take them inand swap them for other, newer, full tanks?2. The hoses appear to be okay (no cracks), but I have not yet pressurized themand sprayed them with soapy water to check for any leaks. Should I just go aheadand buy new ones? I am guessing the hoses have been coiled up easily 6 or8 years since last used.3. The torch it self is a Smith and I have tip sizes 200, 203, and 205. I replacedthe o-rings on the tips. Should I take the torches somewhere to have theminspected? Can they be rebuilt, if needed?4. The regulator is the 2-stage type. Do I need to have them inspected as well?Can they be inspected and repaired if needed?Obviously, I am trying to ensure the equipment is in good working order beforeusing them. Thanks for the advice.--------Semper Fi,Terry HandAthens, GAUSMC, USMCR, ATPBVD DVD PDQ BBQRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: CG vs Wheels Location..emergency situation

Original Posted By: "jarheadpilot82"
Dan,Here is a positive suggestion:What don't you, Don and Mike Cuy, who all have flying planes that you like, Takea few minutes to walk out to your planes, get the weight and balance form outand type it in here, do I can all it to the data base we have for planes. Pleaseinclude your axle and tailwheel location, and your pilot weight. If you guyslike your planes, then share the data with everyone and let them directlycopy your set up if they choose to. Brian sent in a lot of data, but I need toknow the weights to put it in the data base.Jack Phillips sent me an email saying his plane is actually in the CG range withhis pilot weight and set up, It is useful to others to pick which path to followif we can get it in the data set.If you don't like the numerical information, just ignore it. A new builder doesn'tneed to understand every line that Chris and Brian wrote in. I will do themath for them, it is not an issue, I know you guys as pilots can do weight andbalance calculations, don't make it sound hard to new guys, it is a simple formatwith 6th grade math. I don't think flying around out of CG adds to the romanceof flight, nor do I see how having a better fuel line ruins every sunsetflight.-ww.Read this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: CG vs Wheels Location..emergency situation

Original Posted By: "Gary Boothe"
Dan, I would more refer to it as a breath of fresh air. I know that William doesn'tneed anyone to speak for him but I think putting safety and risk managementas a priority is never a bad thing. And I think that that is all that Williamis trying to point out.--------Semper Fi,Terry HandAthens, GAUSMC, USMCR, ATPBVD DVD PDQ BBQRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________

Original Posted By: Rick
William,I think that's a great idea. I think it would be very helpful for builders toget an idea of what a certain set up may look like when it comes to Weight andBalance time. This afternoon I will try to scan my W&B sheet I made up for myPilot's Manual and post it. It's nothing fancy and hand drawn, so no laughing!:-)Don EmchNX899DERead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Re: Pietenpol-List: Re: CG vs Wheels Location..emergency situation

Original Posted By: "tools"
Tom,Are the tips interchangeable, or do I need new ones as well if it is the type youmentioned?Thanks again for your advice.--------Semper Fi,Terry HandAthens, GAUSMC, USMCR, ATPBVD DVD PDQ BBQRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: CG vs Wheels Location..emergency situation

Original Posted By: "dgaldrich"
I don't have all the exact data here, but hopefully somewhat useful.NX2RN, built by Dick N, is a short wood fuse, wing moved back 4 1/2 inches, A65plane.The WB sheet he did showed the CG calculated at around 19.5 inches, with him inthe plane, he's maybe 10 or 20 lbs heavier than I. So I flew it without checking.However, when it came time to teach my son to fly it, wasn't sure if it would bein balance with him being 50 plus pounds lighter than I.So I got GOOD digital race car scales, blocked the plane up level and checked itall empirically, ie with us in the plane to be sure.Turns out it was 19 inches with me, about 17.5 with Scott and VERY suprisingly16.5 inches with ME in the FRONT cockpit. In other words, it showed to be safesoloing from the front! I really thought the plane was more finicky than it turned out to be. Though it's not real stable (ie doesn't return to original position after an upset- gust of wind, control input, etc - quickly), it does fly well and predictably.Not an incredibly easy plane to learn to fly, it does handle a varietyof conditions well. Certainly handles more conditions than really needed, it'sa fun fly plane, not a reliable get you there plane. It requires more headwork than pilot skills. I think it's best to NOT have trim in this plane, as you can't afford to not beconstantly thinking about the condition of flight. It is a little like a jet,predictable and fundamentally easy. If you find yourself in a bad situation,the decision that got you there was (comparatively) long ago and you missedit. You do really have to be ahead of this plane to fly it safely. Wouldn'tthink that is the case at 60 mph...Read this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: cable guides

Original Posted By: owner-pietenpol-list-server(at)matronics.com
Keith,I modified the wooden strip that holds the fabric off the plywood to fitover and around the engine mount brackets as shown below:When the fabric went on, you could net tell where the engine mount boltswere, as shown below:Just make sure that you cover the bolt heads (and anything elese that thefabric might chafe against) with pinked edge tape or a pinked edge patch toprotect the fabric. It's amazing to long alonside the fuselage in flightand see how much drumming takes place with the fabric. If leftunreinforced, any chafing will quickly wear holes right through it.Jack PhillipsNX899JPSmith Mountain Lake, Virginia _____

Original Posted By: "tools"
ToolsThat was a great assesment of the Piet. You do have to find the cruise rpm and the decent rpm and the climb rpm. These are more important than any trim controls. Then as you say stay ahead of the plane.Also listen closely to Will Wynne, I am very grateful Will is posting here.Dick N.----- Original Message -----

Original Posted By: "William Wynne"
Attached is the spreadsheet I use for calculating CG on NX18235. It is an Excel 2007 file.I can enter any combination of weights and it spits out the CG location. Interesting to see how little the CG changes with varying fuel and passenger weights.The numbers briefly:Empty wt. 616 lbsCabanes angled back approx. 3 1/2" from verticalAxle located 6 1/2" aft of the leading edge. This works well, NX18235 was built without brakes.It should be noted that this spreadsheet is unique for NX18235 only.Greg CardinalMinneapolis----- Original Message -----

Original Posted By: jim hyde

Original Posted By:> ----- Original Message ----- "William Wynne"
Donna,Please save this for me.Your Lover!Sent from my iPad> On Mar 22, 2014, at 7:46 PM, "Greg Cardinal" wrote:> > Attached is the spreadsheet I use for calculating CG on NX18235. It is an Excel2007 file.> I can enter any combination of weights and it spits out the CG location. Interestingto see how little the CG changes with varying fuel and passenger weights.> > The numbers briefly:> Empty wt. 616 lbs> Cabanes angled back approx. 3 1/2" from vertical> Axle located 6 1/2" aft of the leading edge. This works well, NX18235 was builtwithout brakes.> > It should be noted that this spreadsheet is unique for NX18235 only.> > Greg Cardinal> Minneapolis>