Brodhead Pietenpol Association

Original Posted By: rmueller23(at)gmail.com
Subject: Re: Pietenpol-List: Re: Brace cables, pulleys, wing supports

Original Posted By: "Charles Campbell"
Am i reading the plans right ??i'm working on the engine mount for the A.. looking at the ash engine supports, the drawing says the front should be 2 1/2 inches lower than the back ?? thatseems like a lot but if its right then i'll build it that wayjeffRead this topic online here:http://forums.matronics.com/viewtopic.p ... ttachments: http://forums.matronics.com//files/moun ... __________

Original Posted By: "Jack Phillips"
Yes, you're reading the plans correctly. I can't recall ever seeing anyone onthis list having any issues with the downthrust of the engine as mounted per theplans. It's been working fairly well for over 80 years now as it was designed,I don't see any point in changing it now.--------Billy McCaskillUrbana, ILtail section almost done, starting on ribs soonRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________

Original Posted By: owner-pietenpol-list-server(at)matronics.com
Hi Mike,Good to have you as a new Pietenpol builder. Welcome to the best group ofpeople on the internet..This is a bunch that has opinions on every subject -Pietenpol or otherwise. Some of these opinions are even useful!As for your questions, I'll give MY opinions, and please remember what theysay about opinions - Opinions are like rectums. Everybody has one and mostof them are full of crap.1. The only real benefit to building one component before the other ispersonal preference. I did wings, then tail, then fuselage. The advantageto doing it that way is that the wings and tail tend to be relatively flatpieces that are easy to store. Once you build the fuselage, you are stuckwith it taking up a good deal of floor space. However this is offset by thefact that you can sit in it and make airplane noises, which can be done withthe wing and tail but they are just not as efficient for that task. Yourbuilding partner is partially correct in saying that you need to buildthings to fit the fuselage (the strut fittings, primarily), but the same canbe said for the wing. Build BOTH before making the fittings. And as MikeCuy points out in his video (the best $20 you can spend, by the way, apartfrom the $80 you need to spend for the four Tony Bingelis books), all of thefittings for the Pietenpol should be lengthened by at least 1/2" to make iteasier to fit the clevis pins in past the fabric.2. The one piece wing is definitely lighter. It is also a pain in the rearto move and store, and even picking it up really needs 3 people so itdoesn't deflect too much in the middle. I'm not sure how much lighter it isthan the 3-piece, but my guess is somewhere around 10 lbs., when you countthe extra wood, the extra fittings and bolts, and the fairings which coverthe gap between the outer panels and the centersection.3. I think the steel fuselage is probably lighter and stronger, but it alsois a lot of trouble to plan ahead for every little fitting and attachment,and welding on tabs so you can something. There are a number of steel fusePiets flying, including Roman Buckholts (sp? - sorry Roman) and the BigPiets from Georgia. It basically depends on how comfortable you are withwelding. Many Pietenpol builders are attracted to the design because itlooks simple and they are familiar with woodworking, little realizing justhow much welding is involved with building a wooden airplane.Build what you want. As long as you don't try to "improve" the design much,you'll end up with a great airplaneGood luck,Jack PhillipsNX899JP "Icarus Plummet"Raleigh, NC-----Original Message-----

Original Posted By: owner-pietenpol-list-server(at)matronics.com
Ryan, you and Gene are arguing over two different things. Gene isreferring to the choice of datum for comparing various different airplanes.Obviously, what matters most (and the reason we even compute weight andbalance) is the relationship of the center of gravity to the center ofpressure (or center of lift, as it is sometimes called). This is usuallystated as the CG falling in some range as a percentage of wing chord, andthe easiest way to relate that is a distance from the leading edge.But when you are doing the w&b on your airplane and trying to decide howmuch to move the wing, it is much easier if a FIXED point of the airframe isused as the datum. I used the firewall on mine, and since that point ispretty close to being the same for all Pietenpols, it makes sense to use itif you are trying to compare several different airplanes. Manufacturerstypically pick a point in front of the airplane (sometimes the prop hub,sometimes a point in space in front of any part of the airplane) so that allarms are positive. If you pick a point on the plane such as the firewall orthe leading edge, anything forward of that has a negative arm which can leadto calculation errors if not recognized.I tend to agree with Gene that picking the leading edge of a wing that youintend to possibly move is not the best choice, since all the variableweights such as pilot, passenger, baggage, fuel, etc. now will have adifferent arm as soon as you move the wing. But choosing the LE is notwrong, just more work.Jack PhillipsNX899JP "Icarus Plummet"Raleigh, NC _____

Original Posted By: Ryan Mueller
Subject: Re: Pietenpol-List: Re: Brace cables, pulleys, wing supports

Original Posted By: Ryan Mueller
Subject: Re: Pietenpol-List: Re: Brace cables, pulleys, wing supports

Original Posted By: "MPB"
Don't forget why it was done in the first place. The Fordhas quite low HP and in takeoff the plane ( well, all AC ),mush through the air. Having the engine point downwardscompensates for this somewhat by aligning the axis ofthe prop closer to the line of flight.Clif>> Yes, you're reading the plans correctly. I can't recall ever seeing > anyone on this list having any issues with the downthrust of the engine as > mounted per the plans. It's been working fairly well for over 80 years > now as it was designed, I don't see any point in changing it now.>> --------> Billy McCaskill________________________________________________________________________________Subject: Pietenpol-List: Re: questions from a new guy...

Original Posted By: "MPB"
i sure thought 2 1/2 inches was too much.... 2 1/2 degrees sounds better.. thanksfor the repliesJeffRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: questions from a new guy...

Original Posted By: Michael Perez
Its funny. You always hear that advise from experienced builders "stick to theplans". The RV crowd says it, boats designs, etc. Yet we can never seem toavoid "tinkering" with the design (I'll refrain from saying "improving"). I guessits part of what draws someone to building, but I appreciate the advise.Like so many discussions the airfoil one seems to have strong opinions on bothsides that will warant some more research. Thanks again,MikeBTW- Gary asked where I am located and I noticed he is from Cool, CA. I live inPrunedale near Monterey Bay. I have family in Placerville. Small world...Read this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Mon, 24 Jan 2011 06:47:15 -0800 (PST)

Original Posted By:> rmueller23(at)gmail.com
> Subject: Re: Pietenpol-List: Re: Brace cables, pulleys, wing supports