Today's Message Index:
----------------------
1. 09:43 AM - Re: Arlington Wa. Fly-in Complete Results (Kenneth Graves)
2. 10:09 AM - Re: Engine for Tailwind (Bill newkirk)
3. 11:18 AM - Re: Emailing: TW JC9 door latch 003 (Malcolm.Lovelace@coopertools.com)
4. 08:21 PM - Scimitar Prop Design (Rcaprd@aol.com)
5. 09:03 PM - Re: Scimitar Prop Design (Fred Weaver)
6. 09:11 PM - Re: Scimitar Prop Design (red)
7. 10:18 PM - Re: Scimitar Prop Design (Larry H)
Message 1
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| Subject: | Re: Arlington Wa. Fly-in Complete Results |
--> Tailwind-List message posted by: Kenneth Graves <kbgraves@yahoo.com>
WOW!! Congratulations everyone I see we were well
represented. Keep up the good work.
Ken
--- George Turner <tailwind222@yahoo.com> wrote:
> http://www.nweaa.org/judging2004.html
>
> CUSTOM BUILT - PLANS
>
> Grand Champion
> N#: X374WT
> Type: Wittman Tailwind
> Owner: Red Hamilton
> Address: Fort Bragg, CA
>
> Reserve Grand Champion
> N#: 168A
> Type: Wittman Tailwind
> Owner: David Magaw
> Address: Sacramento, CA
>
> Champion 1
> N#: 13EG
> Type: Acro Sport II
> Owner: Elton George
> Address: Snohomish, WA
>
> Champion 2
> N#: 96AP
> Type: Bushby Mustang II
> Owner: Ivan Porter
> Address: Winton, CA
>
> Workmanship 1
> N#: 7999H
> Type: Long Eze
> Owner: Tim Sullivan
> Address: Placerville, CA
>
> Workmanship 2
> N#: 9168Q
> Type: Wittman Tailwind
> Owner: Gordon Parker
> Address: Sequim, WA
>
> Workmanship 3
> N#: 8121B
> Type: Acroduster II
> Owner: Mike Mattei
> Address: Bend, OR
>
>
> __________________________________________________
> protection around
__________________________________
Message 2
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| Subject: | Re: Engine for Tailwind |
Seal-Send-Time: Tue, 28 Sep 2004 10:06:55 -0700
Jerry Hey:
A couple of months ago you posted some pictures of a rotary exhaust and engine mount. Could you send them to me again. bilnewkirk@msn.com<mailto:bilnewkirk@msn.com>
Thanks,
Bill
----- >
>
>
>
>
>
>
>
>
Matronics Forums. http://www.matronics.com/contribution
Message 3
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| Subject: | Emailing: TW JC9 door latch 003 |
--> Tailwind-List message posted by: Malcolm.Lovelace@CooperTools.com
Thanks, looks like you are getting close.
> -----Original Message-----
> From: Jim and Donna Clement [SMTP:168x@merr.com]
> Sent: Monday, September 27, 2004 7:01 PM
> To: tailwind-list@matronics.com
> Subject: Tailwind-List: Emailing: TW JC9 door latch 003
>
> Malcolm, Will this help. I will send a couple more. Jim C
> The message is ready to be sent with the following file or link
> attachments:
> TW JC9 door latch 003
>
> Note: To protect against computer viruses, e-mail programs may prevent
> sending or receiving certain types of file attachments. Check your e-mail
>
> security settings to determine how attachments are handled. << File: TW
> JC9 door latch 003.jpg >>
Message 4
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| Subject: | Scimitar Prop Design |
--> Tailwind-List message posted by: Rcaprd@aol.com
I'm going to see if I can kick up any interest in the design of a 'Scimitar
Prop'. I've brought up this subject in years past on this list, but had only
limited interest.
As we all know, a propeller absorbs the energy of the fuel burned in the
engine, and dispenses it in the form of thrust. Whenever energy is
transformed from one form to another, some energy is transformed to some other
form
which is lost to intent of thrust. Energy cannot be created nor destroyed...it's
a fact of physics. Therefore, the more efficiently the 'Potential' energy of
the fuel that is burned, can be transformed into thrust, the less fuel will be
required to perform a given amount of work. A given fixed pitch prop is most
efficient at a specific r.p.m., and a specific forward speed. This is why
adjustable props came into play, and high performance airplanes usually have
Constant Speed Props. Here is where the Scimitar Prop comes in. The blades of
the Scimitar Prop will twist to a lower blade angle for the high thrust
required for takeoff and climb, then once airborne and power is pulled, the prop
unloads and flexes back almost to the blade angle it was carved at. Hence you
have an adjustable blade angle prop, with No Moving Parts !! Pretty cool, huh?
Wood is the chosen material for this design, because it will not fatigue, it's
readily available, and it's relatively easy to work with.
Here are the forces imposed upon a Propeller:
1. Centrifugal Force - Most powerful force, tends to pull the blades
outward away from the hub.
2. Thrust Bending Force - Blade tips bend forward when put under a load.
3. Torque Bending Force - Blades bend opposite the direction of
rotation.
4. Aerodynamic Twisting Force - Twists the blade at the aerodynamic
center of pressure. Tends to twist the blades to High Pitch.
5. Centrifugal Twisting Force - The Mass of the blade, under a
centrifugal force, tends to twist the blades to a Lower Pitch.
6. Vibration Force (Resonance) - Everything has a resonant frequency,
according to the mass, and the location of the mass.
A Scimitar design prop takes advantage of these forces to twist the
blades to a lower blade angle for takeoff and climb, and then when in cruise flight
and power is pulled back, and the prop unloads, the blade angle relaxes back
to a higher blade angle, and you have a cruise prop.
Steve Wittman certainly understood the potential of a scimitar design, as
evidence on the wall of his hanger in Oshkosh.
I still can't understand why all props aren't of scimitar design. With
enough Research and Development, then mass production could easily bring the
additional labor involved, down to a competitive cost. I have searched the
library at Oshkosh, lots of web sites, and asked lots of people about scimitar
props. By far, the best info I've found on it, is the couple of pages in Eric
Clutton's book. I did, however, discover that the concept came about in W.W.I
aircraft. The design showed potential, but what happened on several occasions
was that in a dogfight, the lead plane would go into a dive, in an effort to
escape the aggressor, and the engine / prop would overspeed, then the blades
would begin to flutter, and disintegrate. You can imagine the vibration of a
broken prop blade, and if power wasn't pulled and shut down the engine, it would
then shake the engine right off the plane, and now, with a tail heavy CG
condition, the plane would spin to the ground. Even if the pilot was able to shut
down the engine in time, he was then a glider pilot...easy prey. I believe
when you over-run the prop of a scimitar design, the aerodynamics are what
cause the flutter. I have heard stories about how props de-laminate when using
thin laminates of wood, however these props had the width of the planks in the
conventional direction. The cause of these de-laminations could have been the
technique of construction. The big question, is if any successful props were
built using the parameters that Eric Clutton set forth. I do not know the
answer to that question.
I still plan of building one, but haven't began construction, yet. The
method of construction I would use, is laminates of 1/4" or less, bend each
laminate in a jig, to match the 'S' shape of the prop, and use T88 exclusively,
but to avoid squeezing too much of the adhesive out, by using either scrim
cloth between the laminates, or glass beads in the mixture of epoxy. The type
of
wood would I'll use, is still undecided yet, but the type of types of
acceptable prop wood is called out in the AC 43.13-1A.
Now, the challenge of designing a reliable Scimitar Prop, using the mass
of the blade to twist the blade to a lower blade angle for takeoff and climb,
then back almost to the blade angles that they were cut at, when the prop
unloads. The laminations would be perpendicular to the direction of conventional
props, so as to achieve the dramatic arc of the blades, as set forth by Eric
Cluttons design.
I'm looking for any input, pros or cons, and especially if anyone is
aware of an aircraft that has used this design prop successfully.
Chuck Gantzer
Pietenpol Aircamper
NX770CG
Message 5
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| Subject: | Re: Scimitar Prop Design |
--> Tailwind-List message posted by: "Fred Weaver" <Mytyweav@earthlink.net>
Great ideas and a lot of thought..... but.... If this stuff really
worked, everyone would be using it. What do you think the Reno Racer's do
about props? They do one helluva lot of studying and comparing notes to
find out what works. Because we have our airplanes built under the
Experimental umbrella, you can do a lot of experimenting to determine if
your ideas work or not.. It's a beautiful thing....
My recommendation is as follows.....
First, use a prop for your engine that has already been used and used
successfully...document a variety of results...
Second, build a prop that you think will be better.
Third, make sure you are ready to try it out and mount it up.
fourth, Fly it all over the place taking good notes about speed, rpm and
manifold pressure.
I'm betting that the original prop will probably do a better job... But,
the cool thing is, you were able to prove it.
There was a guy in the VariEze/Long EZ bunch that thought a lot of the same
things... He carved several props and might even still fly in front of one
today but......
They didn't work as good as some of the others that were readily available.
Chuck... I don't even want to come close to discouraging you.....but, this
subject has been beaten about for years...
Thank goodness you can try all the different versions you want... Those
tests will be very informative. We will all be excited to see the results.
Good Luck and Have fun,
Weav
----- Original Message -----
From: <Rcaprd@aol.com>
Subject: Tailwind-List: Scimitar Prop Design
> --> Tailwind-List message posted by: Rcaprd@aol.com
>
> I'm going to see if I can kick up any interest in the design of a
'Scimitar
> Prop'. I've brought up this subject in years past on this list, but had
only
> limited interest.
> As we all know, a propeller absorbs the energy of the fuel burned in
the
> engine, and dispenses it in the form of thrust. Whenever energy is
> transformed from one form to another, some energy is transformed to some
other form
> which is lost to intent of thrust. Energy cannot be created nor
destroyed...it's
> a fact of physics. Therefore, the more efficiently the 'Potential' energy
of
> the fuel that is burned, can be transformed into thrust, the less fuel
will be
> required to perform a given amount of work. A given fixed pitch prop is
most
> efficient at a specific r.p.m., and a specific forward speed. This is why
> adjustable props came into play, and high performance airplanes usually
have
> Constant Speed Props. Here is where the Scimitar Prop comes in. The
blades of
> the Scimitar Prop will twist to a lower blade angle for the high thrust
> required for takeoff and climb, then once airborne and power is pulled,
the prop
> unloads and flexes back almost to the blade angle it was carved at. Hence
you
> have an adjustable blade angle prop, with No Moving Parts !! Pretty cool,
huh?
> Wood is the chosen material for this design, because it will not fatigue,
it's
> readily available, and it's relatively easy to work with.
>
> Here are the forces imposed upon a Propeller:
>
> 1. Centrifugal Force - Most powerful force, tends to pull the blades
> outward away from the hub.
>
> 2. Thrust Bending Force - Blade tips bend forward when put under a
load.
>
> 3. Torque Bending Force - Blades bend opposite the direction of
> rotation.
>
> 4. Aerodynamic Twisting Force - Twists the blade at the aerodynamic
> center of pressure. Tends to twist the blades to High Pitch.
>
> 5. Centrifugal Twisting Force - The Mass of the blade, under a
> centrifugal force, tends to twist the blades to a Lower Pitch.
>
> 6. Vibration Force (Resonance) - Everything has a resonant frequency,
> according to the mass, and the location of the mass.
>
> A Scimitar design prop takes advantage of these forces to twist the
> blades to a lower blade angle for takeoff and climb, and then when in
cruise flight
> and power is pulled back, and the prop unloads, the blade angle relaxes
back
> to a higher blade angle, and you have a cruise prop.
> Steve Wittman certainly understood the potential of a scimitar design,
as
> evidence on the wall of his hanger in Oshkosh.
> I still can't understand why all props aren't of scimitar design.
With
> enough Research and Development, then mass production could easily bring
the
> additional labor involved, down to a competitive cost. I have searched
the
> library at Oshkosh, lots of web sites, and asked lots of people about
scimitar
> props. By far, the best info I've found on it, is the couple of pages in
Eric
> Clutton's book. I did, however, discover that the concept came about in
W.W.I
> aircraft. The design showed potential, but what happened on several
occasions
> was that in a dogfight, the lead plane would go into a dive, in an effort
to
> escape the aggressor, and the engine / prop would overspeed, then the
blades
> would begin to flutter, and disintegrate. You can imagine the vibration
of a
> broken prop blade, and if power wasn't pulled and shut down the engine, it
would
> then shake the engine right off the plane, and now, with a tail heavy CG
> condition, the plane would spin to the ground. Even if the pilot was able
to shut
> down the engine in time, he was then a glider pilot...easy prey. I
believe
> when you over-run the prop of a scimitar design, the aerodynamics are what
> cause the flutter. I have heard stories about how props de-laminate when
using
> thin laminates of wood, however these props had the width of the planks in
the
> conventional direction. The cause of these de-laminations could have been
the
> technique of construction. The big question, is if any successful props
were
> built using the parameters that Eric Clutton set forth. I do not know the
> answer to that question.
> I still plan of building one, but haven't began construction, yet.
The
> method of construction I would use, is laminates of 1/4" or less, bend
each
> laminate in a jig, to match the 'S' shape of the prop, and use T88
exclusively,
> but to avoid squeezing too much of the adhesive out, by using either scrim
> cloth between the laminates, or glass beads in the mixture of epoxy. The
type of
> wood would I'll use, is still undecided yet, but the type of types of
> acceptable prop wood is called out in the AC 43.13-1A.
> Now, the challenge of designing a reliable Scimitar Prop, using the
mass
> of the blade to twist the blade to a lower blade angle for takeoff and
climb,
> then back almost to the blade angles that they were cut at, when the prop
> unloads. The laminations would be perpendicular to the direction of
conventional
> props, so as to achieve the dramatic arc of the blades, as set forth by
Eric
> Cluttons design.
> I'm looking for any input, pros or cons, and especially if anyone is
> aware of an aircraft that has used this design prop successfully.
>
>
> Chuck Gantzer
> Pietenpol Aircamper
> NX770CG
>
>
Message 6
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| Subject: | Re: Scimitar Prop Design |
--> Tailwind-List message posted by: "red" <redswings@reds-headers.com>
Chuck,
I don't know anything that will help you but wish you success. Keep us
informed.
Red
----- Original Message -----
From: <Rcaprd@aol.com>
Subject: Tailwind-List: Scimitar Prop Design
> --> Tailwind-List message posted by: Rcaprd@aol.com
>
> I'm going to see if I can kick up any interest in the design of a
'Scimitar
> Prop'. I've brought up this subject in years past on this list, but had
only
> limited interest.
> As we all know, a propeller absorbs the energy of the fuel burned in
the
> engine, and dispenses it in the form of thrust. Whenever energy is
> transformed from one form to another, some energy is transformed to some
other form
> which is lost to intent of thrust. Energy cannot be created nor
destroyed...it's
> a fact of physics. Therefore, the more efficiently the 'Potential' energy
of
> the fuel that is burned, can be transformed into thrust, the less fuel
will be
> required to perform a given amount of work. A given fixed pitch prop is
most
> efficient at a specific r.p.m., and a specific forward speed. This is why
> adjustable props came into play, and high performance airplanes usually
have
> Constant Speed Props. Here is where the Scimitar Prop comes in. The
blades of
> the Scimitar Prop will twist to a lower blade angle for the high thrust
> required for takeoff and climb, then once airborne and power is pulled,
the prop
> unloads and flexes back almost to the blade angle it was carved at. Hence
you
> have an adjustable blade angle prop, with No Moving Parts !! Pretty cool,
huh?
> Wood is the chosen material for this design, because it will not fatigue,
it's
> readily available, and it's relatively easy to work with.
>
> Here are the forces imposed upon a Propeller:
>
> 1. Centrifugal Force - Most powerful force, tends to pull the blades
> outward away from the hub.
>
> 2. Thrust Bending Force - Blade tips bend forward when put under a
load.
>
> 3. Torque Bending Force - Blades bend opposite the direction of
> rotation.
>
> 4. Aerodynamic Twisting Force - Twists the blade at the aerodynamic
> center of pressure. Tends to twist the blades to High Pitch.
>
> 5. Centrifugal Twisting Force - The Mass of the blade, under a
> centrifugal force, tends to twist the blades to a Lower Pitch.
>
> 6. Vibration Force (Resonance) - Everything has a resonant frequency,
> according to the mass, and the location of the mass.
>
> A Scimitar design prop takes advantage of these forces to twist the
> blades to a lower blade angle for takeoff and climb, and then when in
cruise flight
> and power is pulled back, and the prop unloads, the blade angle relaxes
back
> to a higher blade angle, and you have a cruise prop.
> Steve Wittman certainly understood the potential of a scimitar design,
as
> evidence on the wall of his hanger in Oshkosh.
> I still can't understand why all props aren't of scimitar design.
With
> enough Research and Development, then mass production could easily bring
the
> additional labor involved, down to a competitive cost. I have searched
the
> library at Oshkosh, lots of web sites, and asked lots of people about
scimitar
> props. By far, the best info I've found on it, is the couple of pages in
Eric
> Clutton's book. I did, however, discover that the concept came about in
W.W.I
> aircraft. The design showed potential, but what happened on several
occasions
> was that in a dogfight, the lead plane would go into a dive, in an effort
to
> escape the aggressor, and the engine / prop would overspeed, then the
blades
> would begin to flutter, and disintegrate. You can imagine the vibration
of a
> broken prop blade, and if power wasn't pulled and shut down the engine, it
would
> then shake the engine right off the plane, and now, with a tail heavy CG
> condition, the plane would spin to the ground. Even if the pilot was able
to shut
> down the engine in time, he was then a glider pilot...easy prey. I
believe
> when you over-run the prop of a scimitar design, the aerodynamics are what
> cause the flutter. I have heard stories about how props de-laminate when
using
> thin laminates of wood, however these props had the width of the planks in
the
> conventional direction. The cause of these de-laminations could have been
the
> technique of construction. The big question, is if any successful props
were
> built using the parameters that Eric Clutton set forth. I do not know the
> answer to that question.
> I still plan of building one, but haven't began construction, yet.
The
> method of construction I would use, is laminates of 1/4" or less, bend
each
> laminate in a jig, to match the 'S' shape of the prop, and use T88
exclusively,
> but to avoid squeezing too much of the adhesive out, by using either scrim
> cloth between the laminates, or glass beads in the mixture of epoxy. The
type of
> wood would I'll use, is still undecided yet, but the type of types of
> acceptable prop wood is called out in the AC 43.13-1A.
> Now, the challenge of designing a reliable Scimitar Prop, using the
mass
> of the blade to twist the blade to a lower blade angle for takeoff and
climb,
> then back almost to the blade angles that they were cut at, when the prop
> unloads. The laminations would be perpendicular to the direction of
conventional
> props, so as to achieve the dramatic arc of the blades, as set forth by
Eric
> Cluttons design.
> I'm looking for any input, pros or cons, and especially if anyone is
> aware of an aircraft that has used this design prop successfully.
>
>
> Chuck Gantzer
> Pietenpol Aircamper
> NX770CG
>
>
Message 7
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|
| Subject: | Re: Scimitar Prop Design |
--> Tailwind-List message posted by: "Larry H" <laheze@ev1.net>
There used to be a company that made props called Warneke almost constant
speed props. They made some really good props that used some of the theory
that you are talking about. I do not know if they are still in existence now
or not. The spelling is wrong on Warneke but close, I think it was
pronounced warn e key .
Good Luck
Larry H.
----- Original Message -----
From: "red" <redswings@reds-headers.com>
Subject: Re: Tailwind-List: Scimitar Prop Design
> --> Tailwind-List message posted by: "red" <redswings@reds-headers.com>
>
> Chuck,
> I don't know anything that will help you but wish you success. Keep us
> informed.
> Red
>
> ----- Original Message -----
> From: <Rcaprd@aol.com>
> To: <tailwind-list@matronics.com>
> Sent: Tuesday, September 28, 2004 8:21 PM
> Subject: Tailwind-List: Scimitar Prop Design
>
>
> > --> Tailwind-List message posted by: Rcaprd@aol.com
> >
> > I'm going to see if I can kick up any interest in the design of a
> 'Scimitar
> > Prop'. I've brought up this subject in years past on this list, but had
> only
> > limited interest.
> > As we all know, a propeller absorbs the energy of the fuel burned in
> the
> > engine, and dispenses it in the form of thrust. Whenever energy is
> > transformed from one form to another, some energy is transformed to some
> other form
> > which is lost to intent of thrust. Energy cannot be created nor
> destroyed...it's
> > a fact of physics. Therefore, the more efficiently the 'Potential'
energy
> of
> > the fuel that is burned, can be transformed into thrust, the less fuel
> will be
> > required to perform a given amount of work. A given fixed pitch prop is
> most
> > efficient at a specific r.p.m., and a specific forward speed. This is
why
> > adjustable props came into play, and high performance airplanes usually
> have
> > Constant Speed Props. Here is where the Scimitar Prop comes in. The
> blades of
> > the Scimitar Prop will twist to a lower blade angle for the high thrust
> > required for takeoff and climb, then once airborne and power is pulled,
> the prop
> > unloads and flexes back almost to the blade angle it was carved at.
Hence
> you
> > have an adjustable blade angle prop, with No Moving Parts !! Pretty
cool,
> huh?
> > Wood is the chosen material for this design, because it will not
fatigue,
> it's
> > readily available, and it's relatively easy to work with.
> >
> > Here are the forces imposed upon a Propeller:
> >
> > 1. Centrifugal Force - Most powerful force, tends to pull the blades
> > outward away from the hub.
> >
> > 2. Thrust Bending Force - Blade tips bend forward when put under a
> load.
> >
> > 3. Torque Bending Force - Blades bend opposite the direction of
> > rotation.
> >
> > 4. Aerodynamic Twisting Force - Twists the blade at the aerodynamic
> > center of pressure. Tends to twist the blades to High Pitch.
> >
> > 5. Centrifugal Twisting Force - The Mass of the blade, under a
> > centrifugal force, tends to twist the blades to a Lower Pitch.
> >
> > 6. Vibration Force (Resonance) - Everything has a resonant frequency,
> > according to the mass, and the location of the mass.
> >
> > A Scimitar design prop takes advantage of these forces to twist the
> > blades to a lower blade angle for takeoff and climb, and then when in
> cruise flight
> > and power is pulled back, and the prop unloads, the blade angle relaxes
> back
> > to a higher blade angle, and you have a cruise prop.
> > Steve Wittman certainly understood the potential of a scimitar
design,
> as
> > evidence on the wall of his hanger in Oshkosh.
> > I still can't understand why all props aren't of scimitar design.
> With
> > enough Research and Development, then mass production could easily bring
> the
> > additional labor involved, down to a competitive cost. I have searched
> the
> > library at Oshkosh, lots of web sites, and asked lots of people about
> scimitar
> > props. By far, the best info I've found on it, is the couple of pages
in
> Eric
> > Clutton's book. I did, however, discover that the concept came about in
> W.W.I
> > aircraft. The design showed potential, but what happened on several
> occasions
> > was that in a dogfight, the lead plane would go into a dive, in an
effort
> to
> > escape the aggressor, and the engine / prop would overspeed, then the
> blades
> > would begin to flutter, and disintegrate. You can imagine the vibration
> of a
> > broken prop blade, and if power wasn't pulled and shut down the engine,
it
> would
> > then shake the engine right off the plane, and now, with a tail heavy CG
> > condition, the plane would spin to the ground. Even if the pilot was
able
> to shut
> > down the engine in time, he was then a glider pilot...easy prey. I
> believe
> > when you over-run the prop of a scimitar design, the aerodynamics are
what
> > cause the flutter. I have heard stories about how props de-laminate
when
> using
> > thin laminates of wood, however these props had the width of the planks
in
> the
> > conventional direction. The cause of these de-laminations could have
been
> the
> > technique of construction. The big question, is if any successful props
> were
> > built using the parameters that Eric Clutton set forth. I do not know
the
> > answer to that question.
> > I still plan of building one, but haven't began construction, yet.
> The
> > method of construction I would use, is laminates of 1/4" or less, bend
> each
> > laminate in a jig, to match the 'S' shape of the prop, and use T88
> exclusively,
> > but to avoid squeezing too much of the adhesive out, by using either
scrim
> > cloth between the laminates, or glass beads in the mixture of epoxy.
The
> type of
> > wood would I'll use, is still undecided yet, but the type of types of
> > acceptable prop wood is called out in the AC 43.13-1A.
> > Now, the challenge of designing a reliable Scimitar Prop, using the
> mass
> > of the blade to twist the blade to a lower blade angle for takeoff and
> climb,
> > then back almost to the blade angles that they were cut at, when the
prop
> > unloads. The laminations would be perpendicular to the direction of
> conventional
> > props, so as to achieve the dramatic arc of the blades, as set forth by
> Eric
> > Cluttons design.
> > I'm looking for any input, pros or cons, and especially if anyone is
> > aware of an aircraft that has used this design prop successfully.
> >
> >
> > Chuck Gantzer
> > Pietenpol Aircamper
> > NX770CG
> >
> >
> >
> >
> >
> >
> >
> >
> >
>
>
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