Brodhead Pietenpol Association

Original Posted By: "John McNarry"
Subject: Pietenpol-List: Engine mount and tailfeathersHello to all:My project is coming right along. The engine mount is welded straight, in other words no one inch down and no half to one inch right or left. We are using a cont. 75 HP. Should I mount the vertical tail fin an inch or so over toone side or is it worth messing with?Also do I need to have more incidence in the left wing to compensate for torque and P factor?Any constructive criticisms are welcome. I have seen them all ways. Let the debates begin...Thanks in advance,Max L. DavisArlington Tx ________________________________________________________________________________

Original Posted By: "Shawn Wolk"
I learned to fly (as much as I have 70 hours) in a PA12 sitting in theback seat plus some Cornell 18 hrs & Harvard 7hrs all dual time in theback seat. Had a lesson sitting in the front of a Citabria and found itharder as being on the axis of the yaw deviations from straight ahaeadaren't picked up "by the seat of the pants" quite as soon.John Mc________________________________________________________________________________

Original Posted By: "Oscar Zuniga"
My A-65 powered Piet has the top of the engine mount 1" longer at top. Thiswas done by spacers at the engine mount/firewall. (1" bottom, 2"top) The tailisn't a standard Piet design or mount, but it's offset approx. 3/4" and its notenough. So a small trim tab was added to the rudder to compensate. The one piecewing was rigged with identical incidence on both sides. The tips have approx.1.25" of wash. (this was measured in inches using an incidence jig) The planewill fly with the ball in the center for a long time in stable air. For you cold weather pilots out there. A pic of my Pietenpol won me a hat today on http://www.avweb.com . You just have to bundle up a bit to enjoy it.(it was mild, only -10C) It flew great on skis, and the air was smooth.Shawn WolkC-FRAZ 1932 Pietenpol AircamperC-GZOT Skyhopper 2________________________________________________________________________________

Original Posted By: Andimaxd(at)aol.com
Max,Your P factor will be more pronounced with the engine not tipped down . walt evansNX140DL ----- Original Message -----

Original Posted By: "Michael D Cuy"
For whoever asked, the stall spin on takeoff is related to horsing the shipoff the ground before reaching flying airspeed. A little side slip and asnaproll ensues. I have done it with R/C ships. A weak tailwheel pilot,when about to lose control on the ground, will try to horse it off into theair where control is assumed to be available when in fact it is not, hencethe relation to stall spin accidents with inadequately trained tailwheelpilots.Chris Bobka----- Original Message -----

Original Posted By: "The Hallsten's"
Subject: Re: Pietenpol-List: Engine mount and tailfeathersIn a message dated 1/14/04 9:13:12 PM Central Standard Time, Andimaxd(at)aol.com writes:>Max, The Continental Engine Mount, drawn by A. C. Hanfet, dated 3/15/67, shows a difference of 9/16" in the top and bottom lengths of the mount. I maintained this difference in my engine mount, but made it 8" longer with heavierwall tubing. It doesn't show any right thrust, but I built 1/16" right thrustinto the mount. The Model A engine mount shows a 1" downthrust along the horizontal line. Downthrust helps reduce the 'Pendulum Effect' of a high wing,that the various power settings have. Add power, the nose pitches up, reduce power, the nose lowers, however, even with downthrust built into the engine mount.Also do I need to have more incidence in the left wing to compensate for torque and P factor? >> Do Not rig the wing to compensate for torque or P factor. Different incidence in the wing will cause one wing to stall before the other. Rig thewing with the same amount of incidence all the way across, or maybe a tiny bitof washout at the tips. The plans show rigging the vertical fin straight, but that is with a Model A engine. Offset fins seem to be used with engines of higher power. Mineis set straight, with no rudder trim tab, and I use just a tiny bit of right rudder during high power settings...almost not even noticible by my feet. Youcould rig the leading edge of the vertical fin maybe 1/16" to the Left of ButtLine Zero (BL0) to compensate for engine torque. Corvair engines would be offset to the Right side, since they turn in the opposite direction. P factoris only evident when flying at a high angle of attack, with a high power setting. I would suggest you use large 'fender washers' under the engine mount to put some downthrust, and right thrust.Chuck GantzerNX770CG________________________________________________________________________________