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John.Hines(at)craftontull Guest
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Posted: Fri Aug 11, 2006 7:39 am Post subject: Hinge less ailerons |
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I had an interesting conversation with Jim Younkin over the weekend
about the Zenith 601. For those that don't know, Jim Younkin is
credited with inventing the autopilot and he is the president of
Trutrak. When I told him I was building a 601XL, he rather gruffly
asked what kind of aileron hinge I was using. We then launched into the
normal conversation about how Zenith claims they last longer than a
piano hinge... He then said that questions of reliability weren't then
only reason he didn't like them. He said that flexing metal is not a
hinge, it is a spring. A spring requires more force to move than a
hinge. He talked about the CT2K having spring balanced ailerons and how
even though it was an LSA it required a bigger autopilot servo than a
Bonanza.
After talking to him I thought back to my flight in the demo plane. The
elevator motion was very smooth, but the aileron motion was stiff. But
you need so little aileron motion to maneuver that it didn't bother me.
Does the piano hinge give it better motion? How much weight does it
add?
All I know is that I'm a guy with no pilot's license and a completed
tail kit. Jim Younkin is a hell of a lot smarter than I am. It's hard
to argue with a guy with his credentials. What do you guys think?
John
www.johnsplane.com
John R. Hines
IT Manager
Crafton, Tull & Associates, Inc.
901 N. 47th Street, Suite 200
Rogers, AR 72756
Office: 479-878-2449
Mobile: 479-366-4783
Fax: 479-631-6224
John.Hines(at)craftontull.com
www.craftontull.com
Crafton, Tull & Associates, Inc. exists to anticipate and understand the needs of our clients and provide them with successful solutions.
This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This message contains confidential information and is intended only for the individual named. If you are not the named addressee you should not disseminate, distribute or copy this e-mail. Please notify the sender immediately by e-mail if you have received this e-mail by mistake and delete this e-mail from your system. If you are not the intended recipient you are notified that disclosing, copying, distributing or taking any action in reliance on the contents of this information is strictly prohibited.
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craig(at)craigandjean.com Guest
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Posted: Fri Aug 11, 2006 8:05 am Post subject: Hinge less ailerons |
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If you look in the file archive for this list you can see examples of AP
servos installed in 601's:
www.matronics.com/photoshare/craig(at)craigandjean.com.02.11.2006/
These include servos from Navaid and Treo. I assume at least one of these
planes uses the "skin" hinges. Any of the owners should be able to comment
on their servo performance: Jeff Small, Tony Graziano or Pat Safford.
Quote: | From my point of view I would bet that the force of the wind on the ailerons
generates much more counterforce than the "skin" hinge.
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-- Craig
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admin(at)arachnidrobotics Guest
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Posted: Fri Aug 11, 2006 8:12 am Post subject: Hinge less ailerons |
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I'm definitely going with the hinged aileron, for all of the reasons you mention. Bottom line is, it adds less than two pounds, it's smoother, and there are no negative side effects to the conversion. It was kind of a no-brainer.
It helped my decision having moved the stick on both hinged and 'spring' ailerons. The hinged were what you would expect, smooth. The extended skin 'spring' was noticeably stiffer.
John Hines <John.Hines(at)craftontull.com> wrote:[quote] --> Zenith-List message posted by: "John Hines"
I had an interesting conversation with Jim Younkin over the weekend
about the Zenith 601. For those that don't know, Jim Younkin is
credited with inventing the autopilot and he is the president of
Trutrak. When I told him I was building a 601XL, he rather gruffly
asked what kind of aileron hinge I was using. We then launched into the
normal conversation about how Zenith claims they last longer than a
piano hinge... He then said that questions of reliability weren't then
only reason he didn't like them. He said that flexing metal is not a
hinge, it is a spring. A spring requires more force to move than a
hinge. He talked about the CT2K having spring balanced ailerons and how
even though it was an LSA it required a bigger autopilot servo than a
Bonanza.
After talking to him I thought back to my flight in the demo plane. The
elevator motion was very smooth, but the aileron motion was stiff. But
you need so little aileron motion to maneuver that it didn't bother me.
Does the piano hinge give it better motion? How much weight does it
add?
All I know is that I'm a guy with no pilot's license and a completed
tail kit. Jim Younkin is a hell of a lot smarter than I am. It's hard
to argue with a guy with his credentials. What do you guys think?
John
www.johnsplane.com
John R. Hines
IT Manager
Crafton, Tull & Associates, Inc.
901 N. 47th Street, Suite 200
Rogers, AR 72756
Office: 479-878-2449
Mobile: 479-366-4783
Fax: 479-631-6224
John.Hines(at)craftontull.com
www.craftontull.com
Crafton, Tull & Associates, Inc. exists to anticipate and understand the needs of our clients and provide them with successful solutions.
This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This message contains confidential information and is intended only for the individual named. If you are not the named addressee you should
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daveaustin2(at)can.rogers Guest
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Posted: Fri Aug 11, 2006 8:28 am Post subject: Hinge less ailerons |
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I've had both the bending aileron and the hinged on my 601. The only diff.
is slightly less effort on the stick for normal turns. If you want to roll
the a/c the ailerons are to my mind quite heavy in either format - not much
difference.
Dave Austin 601HDS - 912, Spitfire Mk VIII
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d.goddard(at)ns.sympatico Guest
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Posted: Fri Aug 11, 2006 8:32 am Post subject: Hinge less ailerons |
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p.mulwitz(at)worldnet.att Guest
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Posted: Fri Aug 11, 2006 8:36 am Post subject: Hinge less ailerons |
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Hi John,
I think the choice between hingeless and piano hinge on the ailerons
is one that can go either way with little impact.
I agree with you that the actual design of the Zodiac XL works
without much movement of the ailerons. This is probably because the
actual aileron size is large enough that it doesn't need to move much
to create the roll moment we need for flight. I think of it as the
aileron translating force from the control stick to the airplane
without actually moving a great deal. It is the force rather than
the control surface movement that counts.
This may be different for an autopilot than a human pilot. There
isn't a force feedback system that tells the autopilot how hard it is
pushing on the flight control surface. That leaves actual motion as
the medium it uses to control the plane unlike the human pilot who uses force.
One impact of the hingeless design is it forms a perfect "Gap Seal"
between the aileron and wing. This is highly desirable and shows up
greatly in the low speed control that works so well on the
Zodiac. Again, this has nothing to do with autopilot function which
is primarily used at cruise speeds.
For me the decision is easy. I don't want to give up the fun of
flying to a computer. I am not installing an autopilot in my
plane. That means the hingeless design works best for me.
Best regards,
Paul
XL fuselage
At 08:38 AM 8/11/2006, you wrote:
Quote: |
I had an interesting conversation with Jim Younkin over the weekend
about the Zenith 601. For those that don't know, Jim Younkin is
credited with inventing the autopilot and he is the president of
Trutrak. When I told him I was building a 601XL, he rather gruffly
asked what kind of aileron hinge I was using. We then launched into the
normal conversation about how Zenith claims they last longer than a
piano hinge... He then said that questions of reliability weren't then
only reason he didn't like them. He said that flexing metal is not a
hinge, it is a spring. A spring requires more force to move than a
hinge. He talked about the CT2K having spring balanced ailerons and how
even though it was an LSA it required a bigger autopilot servo than a
Bonanza.
After talking to him I thought back to my flight in the demo plane. The
elevator motion was very smooth, but the aileron motion was stiff. But
you need so little aileron motion to maneuver that it didn't bother me.
Does the piano hinge give it better motion? How much weight does it
add?
All I know is that I'm a guy with no pilot's license and a completed
tail kit. Jim Younkin is a hell of a lot smarter than I am. It's hard
to argue with a guy with his credentials. What do you guys think?
John
www.johnsplane.com
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gk(at)601hd.com Guest
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Posted: Fri Aug 11, 2006 8:39 am Post subject: Hinge less ailerons |
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Regarding the bendy metal hinge design, does anyone know if there a
significant difference in aileron force between the XL and HD/HDS? The
HD/HDS design has full length ailerons, the XL does not. Do you need more
aileron deflection on the XL?
Graham Kirby
601HD
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randy(at)n344rb.com Guest
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Posted: Fri Aug 11, 2006 8:56 am Post subject: Hinge less ailerons |
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I had all the same thoughts when I built my ailerons... My final
determination on the hingeless ailerons came down to drag. This set up is
more streamline and essentially have gap seals built in...
Seems everyone is concerned about weight, but no one is concerned about
drag...??
Randy
XL Wings - Plans Only
http://www.n344rb.com
Do Not Archive
---
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Daniel Vandenberg
Joined: 16 Apr 2006 Posts: 22
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Posted: Fri Aug 11, 2006 9:27 am Post subject: Hinge less ailerons |
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William Wynne,et al commented on this some time ago, as they had removed the hinge-less ailerons on their 601XL taildragger in favor of hinges.
As I recall, their conclusion after this was that the roll forces were slightly lower (slightly improved) in slow flight...but the same at cruise speeds. In the end they concluded that the benefit was minimal.
You can read about this here...about 1/3rd of the way down the page:
http://www.flycorvair.com/hangar1105.html
Dan
John Hines <John.Hines(at)craftontull.com> wrote:[quote] --> Zenith-List message posted by: "John Hines"
I had an interesting conversation with Jim Younkin over the weekend
about the Zenith 601. For those that don't know, Jim Younkin is
credited with inventing the autopilot and he is the president of
Trutrak. When I told him I was building a 601XL, he rather gruffly
asked what kind of aileron hinge I was using. We then launched into the
normal conversation about how Zenith claims they last longer than a
piano hinge... He then said that questions of reliability weren't then
only reason he didn't like them. He said that flexing metal is not a
hinge, it is a spring. A spring requires more force to move than a
hinge. He talked about the CT2K having spring balanced ailerons and how
even though it was an LSA it required a bigger autopilot servo than a
Bonanza.
After talking to him I thought back to my flight in the demo plane. The
elevator motion was very smooth, but the aileron motion was stiff. But
you need so little aileron motion to maneuver that it didn't bother me.
Does the piano hinge give it better motion? How much weight does it
add?
All I know is that I'm a guy with no pilot's license and a completed
tail kit. Jim Younkin is a hell of a lot smarter than I am. It's hard
to argue with a guy with his credentials. What do you guys think?
John
www.johnsplane.com
John R. Hines
IT Manager
Crafton, Tull & Associates, Inc.
901 N. 47th Street, Suite 200
Rogers, AR 72756
Office: 479-878-2449
Mobile: 479-366-4783
Fax: 479-631-6224
John.Hines(at)craftontull.com
www.craftontull.com
Crafton, Tull & Associates, Inc. exists to anticipate and understand the needs of our clients and provide them with successful solutions.
This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This message contains confidential information and is intended only for the individual named. If you are not the named addressee you should not
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dougsnash(at)yahoo.com Guest
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Posted: Fri Aug 11, 2006 10:18 am Post subject: Hinge less ailerons |
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As a CH-701 builder I'm asking this question out of
complete ignorance.
Would there not be a tendancy for the aluminum of a
hingless aileron to work harden at the flex point?
Admittedly I have not looked closely at the aileron
attachment on a CH-601 so I can't picture how it
works. I'm just basing my question on the
descriptions you guys have given.
Doug MacDonald
NW Ontario, Canada
CH-701 Scratch Builder
__________________________________________________
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ggower_99(at)yahoo.com Guest
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Posted: Fri Aug 11, 2006 10:39 am Post subject: Hinge less ailerons |
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All I can comment is that the 601 XL , even with the flexing metal "spring" is lighter in control than most of the airplanes I have flown (from the right seat), so I dont thing it will need a bigger servo. I have Navaid autopilot not installed yet... Maybe Navaid is better
The other way I will be scared to move a lighter stick to any side and make an inadverted roll like flying a Pitts
Saludos
Gary Gower.
Do not archive.
John Hines <John.Hines(at)craftontull.com> wrote:[quote] --> Zenith-List message posted by: "John Hines"
I had an interesting conversation with Jim Younkin over the weekend
about the Zenith 601. For those that don't know, Jim Younkin is
credited with inventing the autopilot and he is the president of
Trutrak. When I told him I was building a 601XL, he rather gruffly
asked what kind of aileron hinge I was using. We then launched into the
normal conversation about how Zenith claims they last longer than a
piano hinge... He then said that questions of reliability weren't then
only reason he didn't like them. He said that flexing metal is not a
hinge, it is a spring. A spring requires more force to move than a
hinge. He talked about the CT2K having spring balanced ailerons and how
even though it was an LSA it required a bigger autopilot servo than a
Bonanza.
After talking to him I thought back to my flight in the demo plane. The
elevator motion was very smooth, but the aileron motion was stiff. But
you need so little aileron motion to maneuver that it didn't bother me.
Does the piano hinge give it better motion? How much weight does it
add?
All I know is that I'm a guy with no pilot's license and a completed
tail kit. Jim Younkin is a hell of a lot smarter than I am. It's hard
to argue with a guy with his credentials. What do you guys think?
John
www.johnsplane.com
John R. Hines
IT Manager
Crafton, Tull & Associates, Inc.
901 N. 47th Street, Suite 200
Rogers, AR 72756
Office: 479-878-2449
Mobile: 479-366-4783
Fax: 479-631-6224
John.Hines(at)craftontull.com
www.craftontull.com
Crafton, Tull & Associates, Inc. exists to anticipate and understand the needs of our clients and provide them with successful solutions.
This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This message contains confidential information and is intended only for the individual named. If you are not the named addressee you should not disseminate, distribute or Stay in the know. Pulse on the new Yahoo.com. [url=http://us.rd.yahoo.com/evt=42974/*http://www.yahoo.com/preview] Check it out.[/url]
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dredmoody(at)cox.net Guest
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Posted: Fri Aug 11, 2006 10:43 am Post subject: Hinge less ailerons |
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I've only flown the 601XL so my opinion is pure conjecture, but I've found with my UL that aileron surface close to the fuselage is as useless as a screen door on a submarine. The air flow is not as smooth there and the result is more drag than roll reaction. Flaps work well there but the ailerons return more roll for effort out near the wingtips.
Ed Moody II
---- Graham Kirby <gk(at)601hd.com> wrote:
Quote: |
Regarding the bendy metal hinge design, does anyone know if there a
significant difference in aileron force between the XL and HD/HDS? The
HD/HDS design has full length ailerons, the XL does not. Do you need more
aileron deflection on the XL?
Graham Kirby
601HD
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Gig Giacona
Joined: 10 Jan 2006 Posts: 1416 Location: El Dorado Arkansas USA
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Posted: Fri Aug 11, 2006 10:44 am Post subject: Re: Hinge less ailerons |
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My feeling on this is we all trusted CH with the design of the aircraft we are flying and I, for one, am going to trust him with the design of the way the aileron is hinged.
That said. I've flown in the factory plane and if the force required to roll the plane is too much for you to do all day on a long cross country you are going to have a lot of trouble picking up individual rivets to build the thing.
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_________________ W.R. "Gig" Giacona
601XL Under Construction
See my progress at www.peoamerica.net/N601WR
Last edited by Gig Giacona on Fri Aug 11, 2006 10:45 am; edited 1 time in total |
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Kevin Bonds
Joined: 09 Jan 2006 Posts: 171 Location: Nashville, Tn
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Posted: Fri Aug 11, 2006 10:48 am Post subject: Hinge less ailerons |
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I doubt you will ever deflect the ailerons far enough to work-harden them.
The "hinge" does not actually bend (ie stretch). I think it is more akin to
the kind of flex you might get when rolling up your aluminum for storage.
Kevin Bonds
Nashville TN
601XL Plans building.
http://home.comcast.net/~kevinbonds
do not archive DO NOT ARCHIVE
--
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_________________ KevinBonds
Nashville, TN
Plans-building Zenith CH601XL w/Corvair Power
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admin(at)arachnidrobotics Guest
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Posted: Fri Aug 11, 2006 10:59 am Post subject: Hinge less ailerons |
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The hinged aileron is his design as well...
Gig Giacona <wr.giacona(at)cox.net> wrote:[quote] --> Zenith-List message posted by: "Gig Giacona"
I feeling on this is we all trusted CH with the design of the aircraft we are flying and I, for one, am going to trust him with the design of the way the aileron is hinged.
That said. I've flown in the factory plane and if the force required to roll the plane is too much for you to do all day on a long cross country you are going to have a lot of trouble picking up individual rivets to build the thing.
--------
W.R. "Gig" Giacona
601XL Under Construction
See my progress at www.peoamerica.net/N601WR
Read this topic online
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dredmoody(at)cox.net Guest
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Posted: Fri Aug 11, 2006 10:59 am Post subject: Hinge less ailerons |
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Good point..... one lister is expressing hesitance to contradict an experienced flyer who doesn't like the design but seems totally okee dokee with not trusting Chris Heintz's design and testing experience. Go figure,
Ed
---- Gig Giacona <wr.giacona(at)cox.net> wrote:
Quote: |
I feeling on this is we all trusted CH with the design of the aircraft we are flying and I, for one, am going to trust him with the design of the way the aileron is hinged.
That said. I've flown in the factory plane and if the force required to roll the plane is too much for you to do all day on a long cross country you are going to have a lot of trouble picking up individual rivets to build the thing.
--------
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=54183#54183
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craig(at)craigandjean.com Guest
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Posted: Fri Aug 11, 2006 11:07 am Post subject: Hinge less ailerons |
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Zenith actually did a life test with a motor flexing a sample. It went tens
of thousands of cycles before short cracks appeared at the ends. I think
they then drilled two stop holes and continued the test. You will die of old
age before this is a real problem.
-- Craig
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randy(at)n344rb.com Guest
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Posted: Fri Aug 11, 2006 11:16 am Post subject: Hinge less ailerons |
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I agree... I'm not sure what the radius of the bend would be from stop to
stop, but I'd bet it's several feet...
Randy
XL Wings - Plans Only
Do Not Archive
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randy(at)n344rb.com Guest
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Posted: Fri Aug 11, 2006 11:25 am Post subject: Hinge less ailerons |
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Here's what Chris Heinz says about the hingeless ailerons:
Whereas a hinge has rotating parts (friction, wear and the need to be
lubricated), the "hingeless hinge" has no parts with relative motion because
the deflection is provided by flexing part 'a' (which is an extension of the
aileron skin). If the length 'a' is of the order of 3/4" to 1", the
thickness of the flexing metal being .016", the metal being 6061-T6, and the
deflection of the aileron a maximum of +/- 15 degrees, we can, using
available deflection statistics for recreational airplanes, calculate the
fatigue life of the metal.
It is some 120,000 hours, which, reduced by the safety factor of 8 (usual
when analysis is performed), amounts to 15,000 hours flying time.
Now to be absolutely sure, we also performed fatigue tests. It was easy to
replace the aileron bellcrank with an electric motor and an eccentric moving
the rod and aileron. We had 3 eccentrics for 3 stages of deflection to
reproduce the above mentioned statistics and, knowing that the motor's RPM
is 1700, we get 100,000 cycles per hour (CPM).
In a relatively short period, the cycles from the statistics could be
applied to the deflection of the aileron for an aircraft utilization of
10,000 flying hours. No crack (not even chipped paint) was noticed.
After that, and just to know if by any bad luck it did crack, do I have to
repair it in the field, or can I fly safely home and fix it in the shop? I
cut a 1/8" notch at both inboard and outboard ends of the flex area with
snips and restarted running the tests.
After the equivalent of another 3 hours, the notch had developed into a
crack reaching on one end the first rivet, and on the other end the second
rivet through the wing skin and rear channel. The test was then continued
for the equivalent of another 10,000 flying hours with no further
deterioration.
The conclusions are: The "flex hinge" is adequate for the intended use
(10,000 flying hours, which is an awful lot of time considering that most of
us fly about 50 hours per year; it's 200 years!). Also, if a (very unlikely)
crack would be discovered at the preflight check, you can safely fly home
and then repair it! I know of at least two Zodiacs having logged over 1600
and 2100 hrs. respectively without any problem, so it definitely works!
A conventional hinged aileron adds weight and does not "look as good" as the
maintenance-free hingeless aileron - with its smooth surface and completely
sealed gap.
You can also read this article online at:
http://www.zenithair.com/kit-data/ht-aileron.html
Thanks,
Randy
XL Wings - Plans Only
http://www.n344rb.com
Do Not Archive
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gboothe(at)calply.com Guest
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Posted: Fri Aug 11, 2006 11:41 am Post subject: Hinge less ailerons |
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I'm making a note in my Palm, "Year 2206 - check ailerons." Thanks Randy!
Gary Boothe
Cool, CA
601 HDSTD, WW Conversion
Tail done, wings almost done....(with hingeless ailerons)
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Here's what Chris Heinz says about the hingeless ailerons:
..The conclusions are: The "flex hinge" is adequate for ... 200 years!.
Randy
XL Wings - Plans Only
http://www.n344rb.com
Do Not Archive
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