---------------------------------------------------------- Zenith-List Digest Archive --- Total Messages Posted Sat 10/25/08: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:32 AM - Re: Re: Which Of Two STOL CH7XX Building Choices? (Jimbo) 2. 01:43 PM - 701/Corvair Info Request (Chris Kehoe) 3. 07:52 PM - Re: My lengthy, upbeat update. (PatrickW) 4. 09:05 PM - Re: 701/Corvair Info Request (Gig Giacona) ________________________________ Message 1 _____________________________________ Time: 07:32:08 AM PST US From: Jimbo Subject: Re: Zenith-List: Re: Which Of Two STOL CH7XX Building Choices? NVH (noise, vibration and harshness, from the auto industry) standpoint is another consideration that has nothing to do with performance. My theory on this is that a three bladed prop on a four cylinder engine kee ps the exhaust and propeller sounds out of phase, making it at least seem q uieter. The same for vibrations. For a six, like the Jab 3300 or Corvair, t hree blades would be worse than two for the same reason. Jim LoBue 601XL/Corvair --- On Fri, 10/24/08, Dirk Zahtilla wrote: From: Dirk Zahtilla Subject: Re: Zenith-List: Re: Which Of Two STOL CH7XX Building Choices? Bryan gives an excellent explanation of prop physics. In a prior plane I built I had an IVO 3 blade electric adjust prop . Because of the size and weight of the plane and engine many factors don't applly. I did however have real world experience as I could in a few minute s switch from 3 to 2 blades. I also could adjust the pitch in flight to get m ax efficiency at any time, i.e. climbing or-cruise. The results were that 3 blades were a bit quieter and smoother (less vibration) and climb was impro ved. With 2 blades top level speed was about 3-4% higher, but of course climb suffered a bit. Remember I was able to adjust the pitch at will so as to ge t the most of the prop in any conditions, so theres no question of making a bad c hoice of pitch. - I preferred the 3 blades for my use as the climb and smoothness was more important to me than a slight speed improvement. The differences were subtle but noticeable. - Dirk Z ________________________________ Message 2 _____________________________________ Time: 01:43:52 PM PST US From: "Chris Kehoe" Subject: Zenith-List: 701/Corvair Info Request Would those building and/or flying a 701 with the Corvair engine PLEASE post some updated info on how things are progressing? PLEASE? Thank you. ________________________________ Message 3 _____________________________________ Time: 07:52:38 PM PST US Subject: Zenith-List: Re: My lengthy, upbeat update. From: "PatrickW" Great update, Rich! I remember when you & I met at Corvair College #11 at Cloverdale, and how I was really struck by how much "in common" our building experiences were. Seeing your progress is like looking a bit into the future at what awaits me. :D Hearing of your progress is very exciting! - Pat -------- Patrick 601XL/Corvair N63PZ (reserved) Read this topic online here: http://forums.matronics.com/viewtopic.php?p=210302#210302 ________________________________ Message 4 _____________________________________ Time: 09:05:16 PM PST US Subject: Zenith-List: Re: 701/Corvair Info Request From: "Gig Giacona" Too my knowlwdge there is only one 701 flying with a Vair. You can get info here.... http://flywithgus.com/page4.html and here.. http://www.flycorvair.com/ [quote="bigeagle(at)telus.net"]Would those building and/or flying a 701 with the Corvair engine PLEASE post some updated info on how things are progressing? PLEASE? Thank you. > [b] -------- W.R. "Gig" Giacona 601XL Under Construction See my progress at www.peoamerica.net/N601WR Read this topic online here: http://forums.matronics.com/viewtopic.php?p=210309#210309 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message zenith-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Zenith-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/zenith-list Browse Digests http://www.matronics.com/digest/zenith-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.