RE: Pietenpol-List: Michael Cuy's Weight & Balance---please see attachment

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RE: Pietenpol-List: Michael Cuy's Weight & Balance---please see attachment

Post by matronics »

Original Posted By: gboothe5(at)comcast.net
Thanks for the clarification. I know how it is messing around with 'what ifs' in the spreadsheet.Yet my basic question remains. What justifications do others use to deviate from the original plans numbers? I see a lot of TLAR (That Looks About Right) reasons. I suspect that=2C as I do=2C everyone needs a bit more useful load available. I have found a variety of numbers in the archives=2C but not much justification in their use.I found a rib strength analysis by Jack Phillips from 2005. I'm going to do some similar arithmetic for the spars to see if I can come up with a reasonable number for max gross weight of the airplane based upon strength (not performance) of the wing.If someone else has already done this=2C I'd appreciate the input.Lorenzo
matronics
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Post by matronics »

Original Posted By:> gboothe5(at)comcast.net
Lorenzo,I went through the spar strength years ago and the wing is strong. May I suggest 1320 as a max number for light sport reasons. I for one believe the wing is capable of more....but. In my case the advantages of not exceeding light sport far outweigh a few more pounds of useful load. Steve E> On Jul 27, 2014, at 3:09 PM, larharris2 Harris wrote:> > Thanks for the clarification. I know how it is messing around with 'what ifs' in the spreadsheet.> > Yet my basic question remains. What justifications do others use to deviate from the original plans numbers? I see a lot of TLAR (That Looks About Right) reasons. I suspect that, as I do, everyone needs a bit more useful load available. I have found a variety of numbers in the archives, but not much justification in their use.> > I found a rib strength analysis by Jack Phillips from 2005. I'm going to do some similar arithmetic for the spars to see if I can come up with a reasonable number for max gross weight of the airplane based upon strength (not performance) of the wing.> > If someone else has already done this, I'd appreciate the input.> > Lorenzo> > >
matronics
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Re: Pietenpol-List: Michael Cuy's Weight & Balance---please see attachment

Post by matronics »

Original Posted By: Steve Emo
Lorenzo=2C That was a mistake. The max gross weight of my Piet is 1289 lbs. I was messing around with pilot and passenger weights to see how CG changed=85and forgot to change it back=85 Gary BootheNX308MB ________________________________________________________________________________Subject: Re: Pietenpol-List: Michael Cuy's Weight & Balance---please see attachment
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