Brodhead Pietenpol Association

Original Posted By: "womenfly2"
Flap works as an air-brake too. Can't do that with a moon cut-out. LOL!--------Read this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: One bladed propeller

Original Posted By: Steven Dortch
Back in September, Douwe wrote-> It just makes it easier. Now I wish I had installed one for the front pit too.A step for the front 'pit is very simple and easy. It adds virtually no weightand points straight ahead, so it adds no drag. Take a look at the port sidegear leg, aft member, in the top two photos here:http://www.flysquirrel.net/piets/CorkyPiet.htmlThere is a short stub of tubing welded to the aft member of the gear leg vee, maybe3" long, with a closed end. I use that little step every single time I needto get anywhere into the front 'pit and it works perfectly. Now, if you'regetting out of the cockpit, you really can't see where to place your foot toget on it, but if someone is helping they can guide your foot onto it. Gettinginto the cockpit is infinitely easier by using that little step.--------Oscar ZunigaMedford, ORAir Camper NX41CC "Scout"A75 powerRead this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Tue, 8 Oct 2013 09:08:28 -0500Subject: Re: Pietenpol-List: Re: One bladed propeller

Original Posted By: "David"
wouldn't a one bladed prop side load the crankshaft/bearing? Putting a bending moment at the hub that isn't there with a two or more bladed design. The trailing blades don't get the clean air the leading blade had.Steve> On Oct 8, 2013, at 10:08 AM, Steven Dortch wrote:> > WF2, Why was it not practical for everyday flying?> > Granted it is a more complex prop and would be more expensive to build. It would require more thought to make sure it was installed correctly. > Once installed and setup, it has all the advantages of an adjustable prop without the additonal hardware and complexity. > > What are the wear issues?> > On my other list there is an aerodynamacyst and he has explaned the advantages of one blade. But quite simply, it is easier to build a two bladed fixed prop.> > On my Vtail it has a two bladed 88 inch prop. This is more efficient than the later and shorter 84 inch prop. Newer models have IO 550s (300HP) that all have 3 blade props. The 3 blade is less efficient, but shorter (less ground strikes) and quieter. Besides it looks "sexier". > > For a given HP about 1000 to 1300 RPM with a big bladed prop (fewer blades is better) is the most efficient. However, most engines make their HP at higher RPM. > >> On Mon, Oct 7, 2013 at 12:42 PM, womenfly2 wrote:>>> >> Seen it fly at Sentimental Journey this year. They did a demo flight comparing a standard prop J-3 to an Everal Prop J-3. Everal prop was hard to beat!>> >> Climbed faster at a more AOA, faster in level flight. Great idea, but was not practical for every day flying.>> >> Cool video!>> WF2>> >> -------->> >> >> >> >> >> >> Read this topic online here:>> >> http://forums.matronics.com/viewtopic.p ... 007#410007>> s List Un/Subscription,>> www.matronics.com/Navigator?Pietenpol-List" target="_blank">http://www.matronics.com/Navigator?Pietenpol-List>> ronics.com/" target="_blank">http://forums.matronics.com>> Matt Dralle, List Admin.>> ====> > > 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D> ________________________________________________________________________________

Original Posted By: owner-pietenpol-list-server(at)matronics.com
Single bladed props were used in the 50s for control line racing models forthis exact reason.I recall that the efficiency of a single bladed prop is only matched bycontra-rotating props, but I could be wrong on that. Like most things. _____

Original Posted By: TOM MICHELLE BRANT
Steve,You're quite correct that a hard-mounted one-blade prop would put significant bending moments into the shaft...shades of crank-snapping Corvairs. You may not have noticed in the video that the one-blade prop is free to move fore and aft about an axis through the hub. This eliminates all the bending moments that a hard-mounted one-blade would produce.Mike HardawayScratched on an iPad with blunt instruments.On Oct 8, 2013, at 8:08 AM, Steve Emo wrote:> wouldn't a one bladed prop side load the crankshaft/bearing? Putting a bending moment at the hub that isn't there with a two or more bladed design. > > The trailing blades don't get the clean air the leading blade had.> > Steve> > On Oct 8, 2013, at 10:08 AM, Steven Dortch wrote:> >> WF2, Why was it not practical for everyday flying?>> >> Granted it is a more complex prop and would be more expensive to build. It would require more thought to make sure it was installed correctly. >> Once installed and setup, it has all the advantages of an adjustable prop without the additonal hardware and complexity. >> >> What are the wear issues?>> >> On my other list there is an aerodynamacyst and he has explaned the advantages of one blade. But quite simply, it is easier to build a two bladed fixed prop.>> >> On my Vtail it has a two bladed 88 inch prop. This is more efficient than the later and shorter 84 inch prop. Newer models have IO 550s (300HP) that all have 3 blade props. The 3 blade is less efficient, but shorter (less ground strikes) and quieter. Besides it looks "sexier". >> >> For a given HP about 1000 to 1300 RPM with a big bladed prop (fewer blades is better) is the most efficient. However, most engines make their HP at higher RPM. >> >> On Mon, Oct 7, 2013 at 12:42 PM, womenfly2 wrote:m>>>> >>> Seen it fly at Sentimental Journey this year. They did a demo flight comparing a standard prop J-3 to an Everal Prop J-3. Everal prop was hard to beat!>>> >>> Climbed faster at a more AOA, faster in level flight. Great idea, but was not practical for every day flying.>>> >>> Cool video!>>> WF2>>> >>> -------->>> >>> >>> >>> >>> >>> >>> Read this topic online here:>>> >>> http://forums.matronics.com/viewtopic.p ... 007#410007>>> s List Un/Subscription,>>> www.matronics.com/Navigator?Pietenpol-List" target="_blank">http://www.matronics.com/Navigator?Pietenpol-List>>> ronics.com/" target="_blank">http://forums.matronics.com>>> Matt Dralle, List Admin.>>> ====> > 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D> ________________________________________________________________________________

Original Posted By: Steven Dortch
Well worth attending.https://corvaircollege.wufoo.com/forms/ ... -----Kevin "Axel" PurteeRebuilding NX899KPAustin/San Marcos, TXRead this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Wed, 9 Oct 2013 07:54:35 -0500Subject: Re: Pietenpol-List: Re: One bladed propeller