Original Posted By: Michael Brusilow
Hi,I am looking at my GN-1 plans and there is a statement that says, "SpecifiedCG range is: 18.1 - 20.7. Is that the outer limits of the CG? Is that whateveryone elses plans specify? The reason I ask is the statement I see onPietenpol plans that says CG should never be over 20".Also, what tension should the cross wires by the struts be? Can't find thatin the plans either.Thanks, Ted________________________________________________________________________________
Pietenpol-List: W&B and wire tension
Pietenpol-List: Re: W&B and wire tension
Original Posted By: Patrick & Rita O'Brien
>Hi,>>I am looking at my GN-1 plans and there is a statement that says,"Specified>CG range is: 18.1 - 20.7. Is that the outer limits of the CG? Is thatwhat>everyone elses plans specify? The reason I ask is the statement I see on>Pietenpol plans that says CG should never be over 20".>>Also, what tension should the cross wires by the struts be? Can't findthat>in the plans either.>>Thanks, TedTed, if you are building a GN-1, place the CG in the range specified. ThePiet is a different airplane. Don't mix them up.I did the wires by feel. When they felt tight enough, ( but not too tight ),that was it.Mike B Piet N687MB ( Mr Sam )>>________________________________________________________________________________
>Hi,>>I am looking at my GN-1 plans and there is a statement that says,"Specified>CG range is: 18.1 - 20.7. Is that the outer limits of the CG? Is thatwhat>everyone elses plans specify? The reason I ask is the statement I see on>Pietenpol plans that says CG should never be over 20".>>Also, what tension should the cross wires by the struts be? Can't findthat>in the plans either.>>Thanks, TedTed, if you are building a GN-1, place the CG in the range specified. ThePiet is a different airplane. Don't mix them up.I did the wires by feel. When they felt tight enough, ( but not too tight ),that was it.Mike B Piet N687MB ( Mr Sam )>>________________________________________________________________________________
Pietenpol-List: Re: W&B and wire tension
Original Posted By: John Greenlee
Subject: Pietenpol-List: Re: W&B and wire tension>Ted- I think the most aft you want to be flying your plane>is about 33% aft of the L.E. of the wing, no ? (rule of thumb>aero engineering)...and that works out to about 21" on the>Piet. My most aft CG loading yields a cg of 19.75" and it flies>ok there, but does better with more fuel in the nose tank.>I don't think you'll ever find a Piet or GN-1 with a 'forward cg problem",>but then again.....>>The cross wire tension on Piets/GN-1's that I have 'twanged' varies all>across the board. I made my tight to where when I pulled on them they>seemed about equal in tension. I didn't like the Piets I flew where I saw>them 'buzzing' /vibrating out in the slipstream. Mine don't flutter or>move in flight and somehow my gut tells me that's good.>I suppose you could use a tensiometer but no one or the plans tell>you what it should read. Maybe one of our wiser members could give you>more insight to my windage method.>>Mike C.>>________________________________________________________________________________
Subject: Pietenpol-List: Re: W&B and wire tension>Ted- I think the most aft you want to be flying your plane>is about 33% aft of the L.E. of the wing, no ? (rule of thumb>aero engineering)...and that works out to about 21" on the>Piet. My most aft CG loading yields a cg of 19.75" and it flies>ok there, but does better with more fuel in the nose tank.>I don't think you'll ever find a Piet or GN-1 with a 'forward cg problem",>but then again.....>>The cross wire tension on Piets/GN-1's that I have 'twanged' varies all>across the board. I made my tight to where when I pulled on them they>seemed about equal in tension. I didn't like the Piets I flew where I saw>them 'buzzing' /vibrating out in the slipstream. Mine don't flutter or>move in flight and somehow my gut tells me that's good.>I suppose you could use a tensiometer but no one or the plans tell>you what it should read. Maybe one of our wiser members could give you>more insight to my windage method.>>Mike C.>>________________________________________________________________________________
Original Posted By: Mike Cunningham
Guys; I am at the point of making the stock model A hub for my Scout.Per the plans and the photos provided by Mike Madrid, the prop "bolts"are threaded on both ends and use a check nut on the engine side of theflange. This secures the back prop plate to the machined hub and then tothe flange. Have you guys that have done this relieved or counter-boredthe back side of the prop to fit over these nuts or???????????? Earl Myers________________________________________________________________________________
Guys; I am at the point of making the stock model A hub for my Scout.Per the plans and the photos provided by Mike Madrid, the prop "bolts"are threaded on both ends and use a check nut on the engine side of theflange. This secures the back prop plate to the machined hub and then tothe flange. Have you guys that have done this relieved or counter-boredthe back side of the prop to fit over these nuts or???????????? Earl Myers________________________________________________________________________________
Pietenpol-List: Re: W&B and wire tension
Original Posted By: Michael D Cuy
Ted- I think the most aft you want to be flying your planeis about 33% aft of the L.E. of the wing, no ? (rule of thumbaero engineering)...and that works out to about 21" on the Piet. My most aft CG loading yields a cg of 19.75" and it fliesok there, but does better with more fuel in the nose tank.I don't think you'll ever find a Piet or GN-1 with a 'forward cg problem", but then again.....The cross wire tension on Piets/GN-1's that I have 'twanged' varies allacross the board. I made my tight to where when I pulled on them theyseemed about equal in tension. I didn't like the Piets I flew where I sawthem 'buzzing' /vibrating out in the slipstream. Mine don't flutter ormove in flight and somehow my gut tells me that's good.I suppose you could use a tensiometer but no one or the plans tellyou what it should read. Maybe one of our wiser members could give youmore insight to my windage method.Mike C.________________________________________________________________________________
Ted- I think the most aft you want to be flying your planeis about 33% aft of the L.E. of the wing, no ? (rule of thumbaero engineering)...and that works out to about 21" on the Piet. My most aft CG loading yields a cg of 19.75" and it fliesok there, but does better with more fuel in the nose tank.I don't think you'll ever find a Piet or GN-1 with a 'forward cg problem", but then again.....The cross wire tension on Piets/GN-1's that I have 'twanged' varies allacross the board. I made my tight to where when I pulled on them theyseemed about equal in tension. I didn't like the Piets I flew where I sawthem 'buzzing' /vibrating out in the slipstream. Mine don't flutter ormove in flight and somehow my gut tells me that's good.I suppose you could use a tensiometer but no one or the plans tellyou what it should read. Maybe one of our wiser members could give youmore insight to my windage method.Mike C.________________________________________________________________________________
Pietenpol-List: Re: W&B and wire tension
Original Posted By: Michael D Cuy
Mike B gave a good answer. Tighten them up tight enough but not too tight.Clever.The old red Piet that Gary and Mehlin keep at Brodhead provided aninteresting study to me. In certain maneuvers you can see the cross wireson the right side of the front cockpit go slack. Hmmmmm.....JMG-----Original Message-----
Mike B gave a good answer. Tighten them up tight enough but not too tight.Clever.The old red Piet that Gary and Mehlin keep at Brodhead provided aninteresting study to me. In certain maneuvers you can see the cross wireson the right side of the front cockpit go slack. Hmmmmm.....JMG-----Original Message-----
Pietenpol-List: Re:
Original Posted By: Earl Myers
Earl,All I can tell you is what I did. I obtained a great deal of assistancefrom Howard Henderson. I carved a homemade prop for the Piet and thenbored it for the Model A bolt pattern. The retaining plate is made froma piece of 1/4" aluminum. Howard insisted we make a centering part byturning a piece of tubing to press into the big shallow on the center ofthe flywheel flange. This matches a hole bored in the prop to a slipfit.The whole thing is held on by AN bolts of the appropriate size. Westill need to have the heads of the bolts drilled for safety wire.JMG -----Original Message-----
Earl,All I can tell you is what I did. I obtained a great deal of assistancefrom Howard Henderson. I carved a homemade prop for the Piet and thenbored it for the Model A bolt pattern. The retaining plate is made froma piece of 1/4" aluminum. Howard insisted we make a centering part byturning a piece of tubing to press into the big shallow on the center ofthe flywheel flange. This matches a hole bored in the prop to a slipfit.The whole thing is held on by AN bolts of the appropriate size. Westill need to have the heads of the bolts drilled for safety wire.JMG -----Original Message-----