---------------------------------------------------------- Zenith601-List Digest Archive --- Total Messages Posted Sun 09/13/09: 3 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 01:50 PM - Re: Cof G - weight and balance (chris Sinfield) 2. 07:20 PM - Re: Re: Cof G - weight and balance (Terry Phillips) 3. 09:04 PM - Re: Cof G - weight and balance (chris Sinfield) ________________________________ Message 1 _____________________________________ Time: 01:50:15 PM PST US Subject: Zenith601-List: Re: Cof G - weight and balance From: "chris Sinfield" Thanks Bryan not many others responded with the answer, I wonder if they all have this reduction in C of G range in their flight manuals.. Maybe someone going to the Zenith get together could ask Seb? Chris Read this topic online here: http://forums.matronics.com/viewtopic.php?p=262820#262820 ________________________________ Message 2 _____________________________________ Time: 07:20:12 PM PST US From: Terry Phillips Subject: Re: Zenith601-List: Re: Cof G - weight and balance Chris You raise an interesting point. The situation is bit more complex than a simple reduction in CG range. A year ago, I found a W&B data sheet on zenithair.com, called wb-xl-new.pdf, with the date 1/02 on it. I can no longer find that document on the site. Of course that doesn't mean it's not there. There's lots of stuff that I can't find on that site. The 1st attached jpg shows a figure from that pdf. Within that past year, I found an AMD POH dated 12/05 on the net which contained that same diagram, see 2nd attach. Those CG ranges are rectangles 20 to 30% of MAC. The AMD POH that was referenced in Zodiac Update of 7/27/09, contains the diagram shown in the 3rd attachment. I presume that shows the reduction you are referring to. Looking at the front of the range, one can see that it now extends forward of the former 20% (12 inch) envelope. But at a reduced take-off weight. The reduced take off weight also applies between 12" and 14". Bryan's explanation sounds plausible. You are right, somebody should ask the Zenair folks what is going on. Terry At 01:49 PM 9/13/2009 -0700, Chris wrote: >Thanks Bryan >not many others responded with the answer, I wonder if they all have this >reduction in C of G range in their flight manuals.. > >Maybe someone going to the Zenith get together could ask Seb? >Chris >> >>Probably because you might not have enough margin in elevator >>authority in the region forward of that line. The higher the weight >>and more forward the CG, the more elevator is needed to keep the nose >>up. Terry Phillips ZBAGer ttp44~at~rkymtn.net Corvallis MT 601XL/Jab 3300 s .. l .. o .. o .. w build kit - Tail, flaps, & ailerons are done; waiting on the wings http://www.mykitlog.com/N47TP/ ________________________________ Message 3 _____________________________________ Time: 09:04:11 PM PST US Subject: Zenith601-List: Re: Cof G - weight and balance From: "chris Sinfield" Spot on the money Terry I wonder what gives.??? I have the older W&B forms as well and that is why I am asking about the changes.. Someone must know the reasons why the change in the AMD manual, how about all you AMD owners, what did they tell you ??? Chris Read this topic online here: http://forums.matronics.com/viewtopic.php?p=262890#262890 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message zenith601-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Zenith601-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/zenith601-list Browse Digests http://www.matronics.com/digest/zenith601-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.