Brodhead Pietenpol Association

Original Posted By: "Oscar Zuniga"
Subject: Pietenpol-List: CG check before and after covering and paintI have seen pictures of many Piets completely assembled including engine andprop minus covering and paint. Was wondering if anyone had done a weight andbalance before and after covering, paint, and adding a cowling.Am starting to design a motor mount and would like to better predict thefinal CG. I would guess that covering the wing wouldn't change the balancemuch but covering the tail and fuselage would shift it slightly to the rearalthough adding a cowling would offset that somewhat.Thanks--Rick Holland"Logic is a wreath of pretty flowers, that smell bad"________________________________________________________________________________

Original Posted By: harvey rule

Original Posted By: "Phillips, Jack"

Original Posted By: "Jack T. Textor"

Original Posted By: harvey rule

Original Posted By: "Rick Holland"
Rick,Haven't done it yet, but here is my plan for weight and balance.The plane will be complete except for motor mount, cowling, and boot cowl.Will then build a scrap wood or tube motor mount which will allow me to slide theengine front and back.Do the weight and balance and slide the engine so the cg is at the center of cgrange.Build the motor mount and cowl.Do the weight and balance again and tilt cabanes to get the cg exact.Build the boot cowl to the location of the cabanes.Skip GaddPS Corvair, short(flyer and glider) fuse, I weigh 155 lbs.Am starting to design a motor mount and would like to better predict the finalCG. I would guess that covering the wing wouldn't change the balance much butcovering the tail and fuselage would shift it slightly to the rear although addinga cowling would offset that somewhat. ThanksRick Holland________________________________________________________________________________Date: Mon, 20 Mar 2006 09:18:04 -0700

Original Posted By: "Phillips, Jack"

Original Posted By: Rick Holland at7000ft(at)gmail.com
Subject: RE: Pietenpol-List: CG check before and after covering and paintRick, Except for the paint on the tail feathers, you should be able to just aboutignore the paint. As for the engine: you know the following---a) you wantthe empty cg to be about 2" ahead of the main gear axles, b) you can get agood approx. of the engines weight from books or by weighing it separately.SOOOOOO do the math. Put the plane sans engine on some scales and see howfar behind the axles the current empty cg is......., arm x mass, calulatehow much forward arm you need with engine's known mass to move the newtotal mass of plane plus engine to a empty cg in front of the axles. Ihad to do this configuration because of my weight of 280 lbs and the factwe used a 0-235 engine. Moved the battery around to insure my loaded cgwas within the 25-32% of wing chord when loaded and flying. Gotta get goodwith the math. After fuel starvation due to some dumb mistake bybuilder/test pilot, screwing up the loaded CG for flight is second mostlikely reason for homebuilder crashes and burns. Gordon BowenOriginal Message:-----------------

Original Posted By: "walt evans"

Original Posted By: "Phillips, Jack"

Original Posted By: "walt evans"

Original Posted By: walt evans
Hey Jack, I have pictures of your plane with a leaf spring tail wheel and the Pietenpoldesigned A-arm style. What are you running now and when did you switch.The A-arm looks like the one Ken Perkins builds. Is this one of them? Gotany good pictures of you reinforced A-Arm?Chris TracySacramento, Ca ----- Original Message -----