Brodhead Pietenpol Association

Original Posted By: "Harvey Plummer"
Scott,Just wait till they go to college, and get their pilot's license! It seems theirexpenses never end; but we're very happy to help them out!RaySent from my iPad> On Oct 9, 2015, at 12:58 PM, AircamperN11MS wrote:> > > Very nice Ray,> > I have noticed that with the grand kids, Christmas got expensive again. I guessthat alone would be a reason to retire from being retired. Wow, that soundedbetter in my head.> > Have a great weekend.> > --------> Scott Liefeld> Flying N11MS since March 1972> Steel Tube> C-85-12> Wire Wheels> Brodhead in 1996> > > > > Read this topic online here:> > http://forums.matronics.com/viewtopic.p ... 784#447784> > > > > > > > > > ________________________________________________________________________________Subject: Pietenpol-List: Tank Shape/Support

Original Posted By: "Catdesigns"
Harvey,A liquid gallon is 231 cubic inches. Therefore, an 18 gallon tank requires a minimumof 4158 cubic inches, not counting the outer dimensions of the tank, straps,etc. So, is there that much room between the front cockpit and the firewall?I do not know. Maybe someone can answer that question.More importantly, have you done computations on your weight and balance accountingfor 108 pounds of fuel in that location forward of the datum, and then theshift in CG when you get down to unusable fuel in the tank? Those are the questionsI would want to get answered before I did too much planning.--------Semper Fi,Terry HandAthens, GARead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Tank Shape/Support

Original Posted By: "taildrags"
HarveySketches of a fuselage tank by Mike Cuy are here.http://westcoastpiet.com/images/Mike%20 ... pgAttached is a sketch I made of a nose tank of about 15 gallons, which is similarto ones depicted in Mike Cuy's often recommended Sport Plane Builder book byTony Bingelis. I don't have a drawing of an 18 gallon tank.When designing my tank, I drew a 3-d model in Sketch-up. It was helpful becauseit can do volume calculations of odd shapes. The software is not too hard tolearn.--------ChrisSacramento, CAWestCoastPiet.comRead this topic online here:http://forums.matronics.com/viewtopic.p ... ttachments: http://forums.matronics.com//files/155_ ... ___Subject: Pietenpol-List: Re: Tank Shape/Support

Original Posted By: Yahoo! Account Service
My guess is that there are dozens of Air Campers that have the same nose tank asMike Cuy's sketch depicts. It's almost exactly what is on the nose of my airplane,and you can get the gist of how it fits in the fuselage here:http://flysquirrel.net/piets/repairs/Im ... PGAlthough the tank on 41CC holds a few ounces one side or the other of 16 gallons,I consider the last couple of gallons in the tank to be unusable because belowthat level, the fuel will not flow reliably to the carburetor by gravity.In fact, in the 3-point attitude (ground ops or slow flight) I can guaranteeyou that it is unusable. Ask me how I know ;o)Now back to the question at hand, which is the Corvair-Piet combination. Hereyou have more options, such as constructing the tank in the same style as theusual nose tank but a bit deeper. Since the Corvair requires an electrical systemand can thus use an electric fuel pump, gravity flow to the carb is not arequirement. However, and as Terry pointed out, do some W&B studies becauseeven though standard Air Campers tend to be tail-heavy, with a Corvair on thenose plus more fuel, plus electrical system, starter, and battery- you may needto look at what 18 gallons of fuel up there will do. You'll definitely needto placard it 'Rear Seat Solo Only' unless you really work some magic with whereyou put the weight.I just ran the W&B spreadsheet for my airplane with another 2 gallons in the tankand although it doesn't change much in the solo configuration (raises the minimumpilot weight at maximum forward CG with full fuel to 112 lbs), it makesthe loading configurations with a passenger a bit fussier. For example, my airplane(empty weight 633) is 5 lbs under max gross of 1088 lbs with 18 gallonsin the tank if I have a standard 170 lb pilot and 170 lb passenger and the CGstays nicely within the envelope all the way down to 3 gallons remaining inthe tank. However, if I have a 210 lb pilot and a 135 lb passenger, I'm at grossand within CG but when I burn it down to only 3 gallons left in the tank,the airplane is 1.1" out of aft end of the CG range and if I get to a short fieldin the afternoon when it's a bit bumpy and I've been in the air for a coupleof hours... low fuel... aft CG... twitchy airplane in the bumpy air... it'sgoing to be light on the stick and easier to stall.If you want to get more fuel capacity, as some have wanted to, there are otheroptions. The deHavilland Moth-style 'hump' centersection wing tank has a pleasingappearance to some eyes, and it moves the fuel to a spot where fuel burndoesn't shift the CG appreciably like it does in the nose tank. By all means,play with a W&B spreadsheet to see what effect all these things will have onyour operating envelope. Build it light to give you the most leeway in payload,build it so the wing and landing gear geometry give the airplane the best attitudein the 3-point configuration, and work out CG loadings on paper beforeyou set things permanently. It's much easier with paper and pencil than doingit with the welding torch, wrenches, shims, weights, and other kludges afterit's built.--------Oscar ZunigaMedford, ORAir Camper NX41CC "Scout"A75 powerRead this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Tue, 13 Oct 2015 08:33:45 -0400 (GMT-04:00)

Original Posted By: "Charles N. Campbell"
Subject: Pietenpol-List: CG and rear seat soloI thought I would do something unusual and change the subject line.First Just to beat the CG drum and refresh Pietenpeople as to the effectsof CG.Aft CG gets the center of Gravity and the elevator too close together. As aresult small elevator inputs result in larger noseup or down tendencies.Also If a Stall develops, an Aft CG causes the plane to enter and stay inthe spin. An aft CG causes the plane to be recovery resistant.A forward CG places the elevator and CG far apart, causing the plane tobecome overly stable. The plane does not want to stall or spin, but it alsodoes not want to raise it's nose and flare for landing. An approach that istoo steep may not be arrested by pulling back on the stick! Resulting in ahard pancake landing.On my list of things to do is to do an accurate weight and balance with ourEAA chapter scales (they come with an EAA member who is a W&B expert for$40. what a bargan.) I will do it: totally empty, with Oil and unusablegas, full nose tank, both tanks full, me on board and two on board. During the past several years I have weighed up to 210 and lost weightdown to 183. I have crept back up to 195 lbs and am now creeping backdown. I can affect my W&B the best by staying at a healthy weight. I am nowold enough that I cannot out exercise my diet.Now for a quick question. I have always thought of my Pietenpol as a rearseat solo only plane. Are there any that can be soloed from the front?Blue Skies,Steve D________________________________________________________________________________Date: Tue, 13 Oct 2015 15:40:11 -0400Subject: Re: Pietenpol-List: CG and rear seat solo

Original Posted By: "taildrags"
When I first bought 2rn, I put my son in the front to start his lessons as we weren'tsure we were cg smart if we put him in the back. He's 130, I'm 180.We did have to rig him up a throttle. He had NO instruments. He actually didquite well, and within about 8 hours of him up there we found scales and checkedeverything out carefully.Surprising results. Us swapping seats only moved the cg 1 1/2 inches forward.With me in the back the plane was sitting around 19 inches, with 20 generallybeing considered max. So we were in great shape.For fun I did calculate me in the front only, well, actually just measured it,and in that configuration the cg was around 15 1/2, with 15 generally being consideredthe limit. So it should be ok... I haven't tried!I do have a few take offs and landings from the front, just not very fun! Themain problem I've seen with Piet landings is not pinning the tail... So an instructorcan help. However, if one were to let one get too far out of hand, someoneup front would be hard pressed to save a landing or ground loop.Read this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: CG and rear seat solo