Original Posted By: "DOUGLAS BLACKBURN"
I was doing my engine test the other day and in the full power run I was able toget 1900 rpm static run with an A-65 and a 72x42 prop. I expected a bit higherrpm. Is this close to what others have gotten?Also reading thru materials from EAA on inspections they talk about a prop log.I went out to the local FBO to buy one and the owner said he doesn't keep themfor J-3's and such, he just makes entries in the airframe log. Does the DARwant to see a Prop log?Dick________________________________________________________________________________
Pietenpol-List: prop
Re: Pietenpol-List: prop
Original Posted By: "Richard Navratil"
Dick,The taylorcraft with an A-65 is min 2070 and max 2250 rpm for static runup.That is with a 70-72 " diameter prop of appropriate pitch to give the staticrange, usually 42-44".Chris bobka----- Original Message -----
Dick,The taylorcraft with an A-65 is min 2070 and max 2250 rpm for static runup.That is with a 70-72 " diameter prop of appropriate pitch to give the staticrange, usually 42-44".Chris bobka----- Original Message -----
Re: Pietenpol-List: prop
Original Posted By: "Leo Gates"
Dick,My DAR never mentioned a prop log. Was only interested in prop serialnumber, so the FAA would take a 25 hour phase 1 fly-off.walt evansNX140DL----- Original Message -----
Dick,My DAR never mentioned a prop log. Was only interested in prop serialnumber, so the FAA would take a 25 hour phase 1 fly-off.walt evansNX140DL----- Original Message -----
Pietenpol-List: prop
Original Posted By: BARNSTMR(at)aol.com
I was just browsing Barnstormers and came across a Sensenich Metal Prop for sale.It's in the antique classic heading for $1500. Listed by Bill Robicheau inMontillo, Wi. 608-429-2899.Dick N.________________________________________________________________________________
I was just browsing Barnstormers and came across a Sensenich Metal Prop for sale.It's in the antique classic heading for $1500. Listed by Bill Robicheau inMontillo, Wi. 608-429-2899.Dick N.________________________________________________________________________________
Pietenpol-List: prop
Original Posted By: Rcaprd(at)aol.com
I was just sitting in front of the t.v. paging thru the Wicks cataloug. I happened to spot on pages 283-284, items called a "Prop Kit". They are a Vortelator device that clain to add 20-50 rpm and increase speed. Has anyone tried one of these? Any power increase with an A-65 would help.Also, I just read the post by Don Emch. I run a Senenich 72-42. His numbers are much better than mine for climb and speed. Does anyone else have a similar prop?Don, do you get a full static run up with that prop? I don't care about the speed but your climb is better than my 200-250 fpm.Dick N.________________________________________________________________________________
I was just sitting in front of the t.v. paging thru the Wicks cataloug. I happened to spot on pages 283-284, items called a "Prop Kit". They are a Vortelator device that clain to add 20-50 rpm and increase speed. Has anyone tried one of these? Any power increase with an A-65 would help.Also, I just read the post by Don Emch. I run a Senenich 72-42. His numbers are much better than mine for climb and speed. Does anyone else have a similar prop?Don, do you get a full static run up with that prop? I don't care about the speed but your climb is better than my 200-250 fpm.Dick N.________________________________________________________________________________
Re: Pietenpol-List: prop
Original Posted By: Clif Dawson
Subject: Re: Pietenpol-List: propIn a message dated 1/7/2007 10:50:59 PM Central Standard Time, horzpool(at)goldengate.net writes:I was just sitting in front of the t.v. paging thru the Wicks cataloug. I happened to spot on pages 283-284, items called a "Prop Kit". They are a Vortelator device that clain to add 20-50 rpm and increase speed. Has anyone triedone of these? Any power increase with an A-65 would help.Also, I just read the post by Don Emch. I run a Senenich 72-42. His numbers are much better than mine for climb and speed. Does anyone else have a similar prop?Don, do you get a full static run up with that prop? I don't care about the speed but your climb is better than my 200-250 fpm.Dick N.Dick,Is that Vortelator device anything like Dimple Tape ? Bill Rewey has that on his prop, and I think he claims that it increased the rpm about 50 rpm.I have my homebuilt 72 / 42 and have similar performance as you do.Gene, Both numbers are in Inches. 72" diameter, and 42" pitch. The pitch is how far the prop will advance in one revolution, with a theoretical No Slip condition.Chuck G.________________________________________________________________________________Date: Sun, 07 Jan 2007 22:09:04 -0800
Subject: Re: Pietenpol-List: propIn a message dated 1/7/2007 10:50:59 PM Central Standard Time, horzpool(at)goldengate.net writes:I was just sitting in front of the t.v. paging thru the Wicks cataloug. I happened to spot on pages 283-284, items called a "Prop Kit". They are a Vortelator device that clain to add 20-50 rpm and increase speed. Has anyone triedone of these? Any power increase with an A-65 would help.Also, I just read the post by Don Emch. I run a Senenich 72-42. His numbers are much better than mine for climb and speed. Does anyone else have a similar prop?Don, do you get a full static run up with that prop? I don't care about the speed but your climb is better than my 200-250 fpm.Dick N.Dick,Is that Vortelator device anything like Dimple Tape ? Bill Rewey has that on his prop, and I think he claims that it increased the rpm about 50 rpm.I have my homebuilt 72 / 42 and have similar performance as you do.Gene, Both numbers are in Inches. 72" diameter, and 42" pitch. The pitch is how far the prop will advance in one revolution, with a theoretical No Slip condition.Chuck G.________________________________________________________________________________Date: Sun, 07 Jan 2007 22:09:04 -0800
Re: Pietenpol-List: prop
Original Posted By: Rcaprd(at)aol.com
Chuck>From what I can see from the pic in the catalog it appears to be a bubble tape. If it will give extra rpm on take off, for $25.00 I'll give it a try.Dick ----- Original Message -----
Chuck>From what I can see from the pic in the catalog it appears to be a bubble tape. If it will give extra rpm on take off, for $25.00 I'll give it a try.Dick ----- Original Message -----
Pietenpol-List: Re: prop
Original Posted By: HelsperSew(at)aol.com
Hi Dick,I've been looking into the prop thing for a little while now. I know the Sensenich72 x 42 is kinda the standard for the A-65, but I think just about all ofthe planes that use that engine/prop combination are cleaner than the Piet. I've talked to a few prop builders and I've had three of them say a 74 x 38 or74 x 40 would be good. I know mine is going the other direction than yours butI also think each plane is different. Weight is obviously always against climband I think other less noticeable things affect it too. Among other thingsI think the bluntness of the cowl matters because it affects the useful airthat is entering the prop 'disk'. I pirated and copied an awful lot of thingsfrom Frank Pavliga's Sky Gypsy. Our empty weights are within a pound of eachother! The only real difference is his has the straight axle gear and minehas the split axle. He is running a Falcon 72 x 44 (I think the Falcon must beone of the best props out there). I have the Hegy 72 x 44. Even though theyare very very similar I cannot catch him in a climb! On one occasion he evenhad his son with him while I was by myself and he took off slightly behind meand I couldn't get away from him!! Go figure! Then there's that Mike Cuy guy,he just has to be packing more than 65 hp!Don EmchNX899DERead this topic online here:http://forums.matronics.com/viewtopic.p ... __________
Hi Dick,I've been looking into the prop thing for a little while now. I know the Sensenich72 x 42 is kinda the standard for the A-65, but I think just about all ofthe planes that use that engine/prop combination are cleaner than the Piet. I've talked to a few prop builders and I've had three of them say a 74 x 38 or74 x 40 would be good. I know mine is going the other direction than yours butI also think each plane is different. Weight is obviously always against climband I think other less noticeable things affect it too. Among other thingsI think the bluntness of the cowl matters because it affects the useful airthat is entering the prop 'disk'. I pirated and copied an awful lot of thingsfrom Frank Pavliga's Sky Gypsy. Our empty weights are within a pound of eachother! The only real difference is his has the straight axle gear and minehas the split axle. He is running a Falcon 72 x 44 (I think the Falcon must beone of the best props out there). I have the Hegy 72 x 44. Even though theyare very very similar I cannot catch him in a climb! On one occasion he evenhad his son with him while I was by myself and he took off slightly behind meand I couldn't get away from him!! Go figure! Then there's that Mike Cuy guy,he just has to be packing more than 65 hp!Don EmchNX899DERead this topic online here:http://forums.matronics.com/viewtopic.p ... __________
Re: Pietenpol-List: prop
Original Posted By: Dick Navratil
The prop on NX18235 is a home made copy of a Sensenich 72 - 42. Max static rpm is 2100, max cruise rpm is ~2250 (giving 80 mph) 200 fpm climb from a 900' field elevation on an 80 deg. F. day at about 1050 pounds. Did a climb test this past summer and the climb rate at 6000 msl was equal to the climb rate passing through 2000' msl. 35 minutes after launching I was passing through 8000' and getting too cold to continue.The low rpm might be due to the leading edge of the prop being too blunt. It has just been recarved.Greg Cardinal ----- Original Message -----
The prop on NX18235 is a home made copy of a Sensenich 72 - 42. Max static rpm is 2100, max cruise rpm is ~2250 (giving 80 mph) 200 fpm climb from a 900' field elevation on an 80 deg. F. day at about 1050 pounds. Did a climb test this past summer and the climb rate at 6000 msl was equal to the climb rate passing through 2000' msl. 35 minutes after launching I was passing through 8000' and getting too cold to continue.The low rpm might be due to the leading edge of the prop being too blunt. It has just been recarved.Greg Cardinal ----- Original Message -----
Re: Pietenpol-List: Re: prop
Original Posted By: "Don Emch"
DonYou climb rate is so much better than mine that I would consider switching props.Dick N.----- Original Message -----
DonYou climb rate is so much better than mine that I would consider switching props.Dick N.----- Original Message -----
Pietenpol-List: Re: prop
Original Posted By: "walt evans"
Hi Dick,I would try to borrow one before I bought. Theoretically you should get betterclimb with with a lower pitch. If you are very serious about buying I wouldtalk to some custom prop builders and based on information that you give themthey can tailor one to suit you. A few of these guys are;Culver PropsSt. Croix PropsSterba PropsI don't have their info. close by but I know they all have websites and I havepersonally talked with them. Ed Sterba actually carves each one by hand and canmake virtually make almost any profile.Another thing to pay attention to is that a 72 x 42 from one company is not necessarilya 72 x 42 from another company. Then there are different airfoils, shapes,chords, etc. It almost hurts when you start to think just how differentone make of prop could be from another make!Good Luck!Don EmchRead this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Tue, 09 Jan 2007 00:00:51 -0500
Hi Dick,I would try to borrow one before I bought. Theoretically you should get betterclimb with with a lower pitch. If you are very serious about buying I wouldtalk to some custom prop builders and based on information that you give themthey can tailor one to suit you. A few of these guys are;Culver PropsSt. Croix PropsSterba PropsI don't have their info. close by but I know they all have websites and I havepersonally talked with them. Ed Sterba actually carves each one by hand and canmake virtually make almost any profile.Another thing to pay attention to is that a 72 x 42 from one company is not necessarilya 72 x 42 from another company. Then there are different airfoils, shapes,chords, etc. It almost hurts when you start to think just how differentone make of prop could be from another make!Good Luck!Don EmchRead this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Tue, 09 Jan 2007 00:00:51 -0500
Re: Pietenpol-List: Re: prop
Original Posted By: Rcaprd(at)aol.com
Subject: Re: Pietenpol-List: Re: propIn a message dated 1/8/2007 9:52:53 PM Central Standard Time, EmchAir(at)aol.com writes:Another thing to pay attention to is that a 72 x 42 from one company is not necessarily a 72 x 42 from another company. Then there are different airfoils,shapes, chords, etc. It almost hurts when you start to think just how different one make of prop could be from another make!Well said, Don.Chuck G.________________________________________________________________________________
Subject: Re: Pietenpol-List: Re: propIn a message dated 1/8/2007 9:52:53 PM Central Standard Time, EmchAir(at)aol.com writes:Another thing to pay attention to is that a 72 x 42 from one company is not necessarily a 72 x 42 from another company. Then there are different airfoils,shapes, chords, etc. It almost hurts when you start to think just how different one make of prop could be from another make!Well said, Don.Chuck G.________________________________________________________________________________
Pietenpol-List: prop
Original Posted By: Ryan M
Re: Pietenpol-List: prop
Original Posted By: "airlion"
ream.net>It's my understanding that the only reason the designers of a airplane stipulate a 3- or 4-bladed prop is that the ground clearance is not sufficient for a 2-bladed prop.- In fact there was a lot or research done in the 40's and 50's (I think) on a single-bladed prop to try to get better efficiency.- It didn't work out probably because of an unbalance situation. The more blades rotating in disturbed air the less efficient the prop.- So putting a 3-blade prop on your Piet would probably reduce the performance. As one on the list says, "My 2 cents."----- Original Message -----
ream.net>It's my understanding that the only reason the designers of a airplane stipulate a 3- or 4-bladed prop is that the ground clearance is not sufficient for a 2-bladed prop.- In fact there was a lot or research done in the 40's and 50's (I think) on a single-bladed prop to try to get better efficiency.- It didn't work out probably because of an unbalance situation. The more blades rotating in disturbed air the less efficient the prop.- So putting a 3-blade prop on your Piet would probably reduce the performance. As one on the list says, "My 2 cents."----- Original Message -----
Re: Pietenpol-List: prop
Original Posted By: "airlion"
cncampbell@windstream.net>It's my understanding that the only reason the designers of a airplanestipulate a 3- or 4-bladed prop is that the ground clearance is notsufficient for a 2-bladed prop. In fact there was a lot or research done inthe 40's and 50's (I think) on a single-bladed prop to try to get betterefficiency. It didn't work out probably because of an unbalance situation.The more blades rotating in disturbed air the less efficient the prop. Soputting a 3-blade prop on your Piet would probably reduce the performance.As one on the list says, "My 2 cents."----- Original Message -----
cncampbell@windstream.net>It's my understanding that the only reason the designers of a airplanestipulate a 3- or 4-bladed prop is that the ground clearance is notsufficient for a 2-bladed prop. In fact there was a lot or research done inthe 40's and 50's (I think) on a single-bladed prop to try to get betterefficiency. It didn't work out probably because of an unbalance situation.The more blades rotating in disturbed air the less efficient the prop. Soputting a 3-blade prop on your Piet would probably reduce the performance.As one on the list says, "My 2 cents."----- Original Message -----
Re: Pietenpol-List: prop
Original Posted By: "airlion"
It's my understanding that the only reason the designers of a airplane stipulate a 3- or 4-bladed prop is that the ground clearance is not sufficient for a 2-bladed prop. In fact there was a lot or research done in the 40's and 50's (I think) on a single-bladed prop to try to get better efficiency. It didn't work out probably because of an unbalance situation. The more blades rotating in disturbed air the less efficient the prop. So putting a 3-blade prop on your Piet would probably reduce the performance. As one on the list says, "My 2 cents." ----- Original Message -----
It's my understanding that the only reason the designers of a airplane stipulate a 3- or 4-bladed prop is that the ground clearance is not sufficient for a 2-bladed prop. In fact there was a lot or research done in the 40's and 50's (I think) on a single-bladed prop to try to get better efficiency. It didn't work out probably because of an unbalance situation. The more blades rotating in disturbed air the less efficient the prop. So putting a 3-blade prop on your Piet would probably reduce the performance. As one on the list says, "My 2 cents." ----- Original Message -----
Re: Pietenpol-List: prop
Original Posted By: "airlion"
It's my understanding that the only reason the designers of a airplane stipulate a 3- or 4-bladed prop is that the ground clearance is not sufficient for a 2-bladed prop. In fact there was a lot or research done in the 40's and 50's (I think) on a single-bladed prop to try to get better efficiency. It didn't work out probably because of an unbalance situation. The more blades rotating in disturbed air the less efficient the prop. So putting a 3-blade prop on your Piet would probably reduce the performance. As one on the list says, "My 2 cents."----- Original Message -----
It's my understanding that the only reason the designers of a airplane stipulate a 3- or 4-bladed prop is that the ground clearance is not sufficient for a 2-bladed prop. In fact there was a lot or research done in the 40's and 50's (I think) on a single-bladed prop to try to get better efficiency. It didn't work out probably because of an unbalance situation. The more blades rotating in disturbed air the less efficient the prop. So putting a 3-blade prop on your Piet would probably reduce the performance. As one on the list says, "My 2 cents."----- Original Message -----
Re: Pietenpol-List: prop
Original Posted By: Charles Campbell
Subject: Re: Pietenpol-List: propAn excerpt from a post William just put up on the Corvaircraft list:"BTW, I am willing to bet that no direct drive corvair will ever performbetter with a three blade thana two blade prop. A number of people have asked about this reciently. Theprimary thing people in light aircraftare seeking with 3 blade props is smoothness out of a for cylinder engine.Since we already have smoothness,there is nothing to be gained, so keep looking at two blades forperformance. Notice that Glassair IIIs withsix cylinder 540cid Lycomings always have two blade props, but the GalssairIIs with 360 cid four cylinder enginesmostly have three blades. Smoothness vs performance."RyanSent from my iPhoneOn Jun 11, 2011, at 9:27 AM, KM Heide CPO/FAAOP wrote:Charles,Much agreed. When speaking with the manufacturer (Warp Drive) I discussedmany of the same issues between two blade verses three blade. The overallout come of the conversation - if you want a smoother prop and a quiet prop,three blade is your answer. The tractor cut through the air is more efficentwith a two blade prop than a three blade prop. However, even based on theadjustable pitch you get a some differences but more on the smoothness thanbite through the air.Also, in my experiences between using the three blade verses the two blade,the three blade prop acts much like and air brake when you throttle back somake sure you are over the fence line as it will decrease your speed in ahurry. My .02 cents worth....KMHeide****--- On *Sat, 6/11/11, Charles Campbell * wrote:
Subject: Re: Pietenpol-List: propAn excerpt from a post William just put up on the Corvaircraft list:"BTW, I am willing to bet that no direct drive corvair will ever performbetter with a three blade thana two blade prop. A number of people have asked about this reciently. Theprimary thing people in light aircraftare seeking with 3 blade props is smoothness out of a for cylinder engine.Since we already have smoothness,there is nothing to be gained, so keep looking at two blades forperformance. Notice that Glassair IIIs withsix cylinder 540cid Lycomings always have two blade props, but the GalssairIIs with 360 cid four cylinder enginesmostly have three blades. Smoothness vs performance."RyanSent from my iPhoneOn Jun 11, 2011, at 9:27 AM, KM Heide CPO/FAAOP wrote:Charles,Much agreed. When speaking with the manufacturer (Warp Drive) I discussedmany of the same issues between two blade verses three blade. The overallout come of the conversation - if you want a smoother prop and a quiet prop,three blade is your answer. The tractor cut through the air is more efficentwith a two blade prop than a three blade prop. However, even based on theadjustable pitch you get a some differences but more on the smoothness thanbite through the air.Also, in my experiences between using the three blade verses the two blade,the three blade prop acts much like and air brake when you throttle back somake sure you are over the fence line as it will decrease your speed in ahurry. My .02 cents worth....KMHeide****--- On *Sat, 6/11/11, Charles Campbell * wrote:
Pietenpol-List: Re: prop
Original Posted By: airlion
For Dan,Here is a photo of a four bladed prop on a Vickers Vimy. It is from a recent visitto the RAF Museum in London.It is a beautifully carved prop, so maybe it will motivate you. I would love tosee it if you ever decide to do one.--------Semper Fi,TerryRead this topic online here:http://forums.matronics.com/viewtopic.p ... ttachments: http://forums.matronics.com//files/img_ ... ______Date: Sat, 11 Jun 2011 15:43:22 -0700 (PDT)
For Dan,Here is a photo of a four bladed prop on a Vickers Vimy. It is from a recent visitto the RAF Museum in London.It is a beautifully carved prop, so maybe it will motivate you. I would love tosee it if you ever decide to do one.--------Semper Fi,TerryRead this topic online here:http://forums.matronics.com/viewtopic.p ... ttachments: http://forums.matronics.com//files/img_ ... ______Date: Sat, 11 Jun 2011 15:43:22 -0700 (PDT)
Original Posted By: jarheadpilot82
Wow Terry, That is one gorgeous prop. If I ever get around to it, I'll for sure try to make it to Brodhead, God willing. This is just a dream at this point., but then again my whole airplane was just a dream also................Dan HelsperPuryear, TN-----Original Message-----
Wow Terry, That is one gorgeous prop. If I ever get around to it, I'll for sure try to make it to Brodhead, God willing. This is just a dream at this point., but then again my whole airplane was just a dream also................Dan HelsperPuryear, TN-----Original Message-----
Pietenpol-List: Re: prop
Original Posted By: Michael Perez
Re: Pietenpol-List: prop
Original Posted By: KM Heide CPO/FAAOP
When he asked about performance I figured he wanted to know if the plane would perform better -- not sound quieter. I never even considered the noise. Most people want their airplane to be LOUD. :>) ----- Original Message -----
When he asked about performance I figured he wanted to know if the plane would perform better -- not sound quieter. I never even considered the noise. Most people want their airplane to be LOUD. :>) ----- Original Message -----
Re: Pietenpol-List: prop
Original Posted By: steve emo
Subject: Re: Pietenpol-List: prop
Subject: Re: Pietenpol-List: prop
Pietenpol-List: Re: prop
Original Posted By: "olflyr45"
Built in 2002 and has flown about 200 hours. No engine. Has a mount for a ContinentalA or C series or an O-200. Needs some rib repair in the left wing. I would strip the whole airplane and recover it just to see everything. Currentlydisassembled for trailering. If you're planning to build one here is a wayto get flying two or three years sooner. Also have a mid time A-65 which wouldbe an ideal unit for it. ($3,500). Reply to wyliejohnson45(at)gmail.com andI'll send pictures. Located in Knoxville TNRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: prop
Built in 2002 and has flown about 200 hours. No engine. Has a mount for a ContinentalA or C series or an O-200. Needs some rib repair in the left wing. I would strip the whole airplane and recover it just to see everything. Currentlydisassembled for trailering. If you're planning to build one here is a wayto get flying two or three years sooner. Also have a mid time A-65 which wouldbe an ideal unit for it. ($3,500). Reply to wyliejohnson45(at)gmail.com andI'll send pictures. Located in Knoxville TNRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: prop
Original Posted By: Jim Boyer
Remember, you don't get something for nothing. If your 2 blade is absorbing allthe horsepower the Corvair can produce you will actually lose performance dueto the additional parasite drag of that 3rd blade. Possible benefits: The blades can be shorter and increase ground clearance. Reduced tip speeds from the smaller diameter can reduce the noise. You can letit turn a little faster and maybe gain some horsepower. It might help takeoffand climb but not likely to do any good at cruise. Higher fuel burn if youdo that.Read this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Tue, 14 Jun 2011 19:57:06 +0000 (UTC)
Remember, you don't get something for nothing. If your 2 blade is absorbing allthe horsepower the Corvair can produce you will actually lose performance dueto the additional parasite drag of that 3rd blade. Possible benefits: The blades can be shorter and increase ground clearance. Reduced tip speeds from the smaller diameter can reduce the noise. You can letit turn a little faster and maybe gain some horsepower. It might help takeoffand climb but not likely to do any good at cruise. Higher fuel burn if youdo that.Read this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Tue, 14 Jun 2011 19:57:06 +0000 (UTC)
Re: Pietenpol-List: Re: prop
Original Posted By: helspersew(at)aol.com
>>>>>>>>>>It's my understanding that the only reason the designers of a airplane stipulate>>a 3- or 4-bladed prop is that the ground clearance is not sufficient for a >>2-bladed prop. In fact there was a lot or research done in the 40's and 50's(I >>think) on a single-bladed prop to try to get better efficiency. It didn't work>>out probably because of an unbalance situation. The more blades rotating in >>disturbed air the less efficient the prop. So putting a 3-blade prop on your>>Piet would probably reduce the performance. As one on the list says, "My 2 >>cents.">>>>----- Original Message ----->>From: "airlion" >>To: >>Sent: Friday, June 10, 2011 8:42 PM>>Subject: Pietenpol-List: prop>>>>>>> >>> Right now I have a 2 blade warp drive on my corvair powered pietenpol. What>>>kind>>> of performance would I get with a 3 blade prop? Gardiner>>> >>> >>> >>matronics.com/Navigator?Pietenpol-List" target=_blank>http://www.matronic; >> --> >>>>>>>> > ">http://www.matronics.com/Navigator?Pietenpol-List >rums.matronics.com">http://forums.matronics.com>"http://www.matronics.com/contribution">http://www.matronics.com/contribution>>________________________________________________________________________________Subject: Re: Pietenpol-List: Re: prop
>>>>>>>>>>It's my understanding that the only reason the designers of a airplane stipulate>>a 3- or 4-bladed prop is that the ground clearance is not sufficient for a >>2-bladed prop. In fact there was a lot or research done in the 40's and 50's(I >>think) on a single-bladed prop to try to get better efficiency. It didn't work>>out probably because of an unbalance situation. The more blades rotating in >>disturbed air the less efficient the prop. So putting a 3-blade prop on your>>Piet would probably reduce the performance. As one on the list says, "My 2 >>cents.">>>>----- Original Message ----->>From: "airlion" >>To: >>Sent: Friday, June 10, 2011 8:42 PM>>Subject: Pietenpol-List: prop>>>>>>> >>> Right now I have a 2 blade warp drive on my corvair powered pietenpol. What>>>kind>>> of performance would I get with a 3 blade prop? Gardiner>>> >>> >>> >>matronics.com/Navigator?Pietenpol-List" target=_blank>http://www.matronic; >> --> >>>>>>>> > ">http://www.matronics.com/Navigator?Pietenpol-List >rums.matronics.com">http://forums.matronics.com>"http://www.matronics.com/contribution">http://www.matronics.com/contribution>>________________________________________________________________________________Subject: Re: Pietenpol-List: Re: prop
> Re: Pietenpol-List: prop
Original Posted By:> "airlion"
>> cncampbell@windstream.net> >>> It's my understanding that the only reason the designers of a airplane> stipulate a 3- or 4-bladed prop is that the ground clearance is not> sufficient for a 2-bladed prop. In fact there was a lot or research done in> the 40's and 50's (I think) on a single-bladed prop to try to get better> efficiency. It didn't work out probably because of an unbalance situation.> The more blades rotating in disturbed air the less efficient the prop. So> putting a 3-blade prop on your Piet would probably reduce the performance.> As one on the list says, "My 2 cents.">> ----- Original Message -----
>> cncampbell@windstream.net> >>> It's my understanding that the only reason the designers of a airplane> stipulate a 3- or 4-bladed prop is that the ground clearance is not> sufficient for a 2-bladed prop. In fact there was a lot or research done in> the 40's and 50's (I think) on a single-bladed prop to try to get better> efficiency. It didn't work out probably because of an unbalance situation.> The more blades rotating in disturbed air the less efficient the prop. So> putting a 3-blade prop on your Piet would probably reduce the performance.> As one on the list says, "My 2 cents.">> ----- Original Message -----