Brodhead Pietenpol Association

Original Posted By: owner-pietenpol-list-server(at)matronics.com
John,Any vertical surface area forward of the Center of Pressure will tend todestabilize. This is why we see floatplanes with additional verticalsurface area aft to offset the destabilizing effect of the float's verticalsurfaces forward, the majority of which are forward.Since the A-65 is lighter than the Model A, it is imperative that the motorbe mounted farther forward to keep the ship in balance. The additionalcowling area needed will destabilize. Those that have used the spokedwheels that are fabric covered have also noticed(complained) about thedestabilizing effect.A fix would be to build slightly oversize vertical stab and rudder, moresothe stabilizer. No one would really notice and you would have a sweeterflying ship. This would have to be worked into the design from day one ofthe fuselage build up.Chris BobkaTech Counselor-----Original Message-----

Original Posted By: "Christian Bobka"
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Original Posted By: owner-pietenpol-list-server(at)matronics.com
That is way my intuition sensed it to be. I have stopped the building of theairframe untill I have an engine that I think is suitable. I was gifted aCirrus from an early Dh Moth and for a while was excited about itspotential. However I still need to find one more good cylinder head. So.. itis back to the modified Ford B. The question I asked has to do of coursewith the choice of engine. The shorter moment arm of wing forward with theheavier engine should in my mind make for a more stable setup. The finalweight of my engine conversion will then get me back to passing the 1" thickstage. Thanks for your input,John-----Original Message-----