Matronics Email Lists Forum Index Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
 
 Get Email Distribution Too!Get Email Distribution Too!    FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Woodcomp Propellers
Goto page Previous  1, 2
 
Post new topic   Reply to topic    Matronics Email Lists Forum Index -> Europa-List
View previous topic :: View next topic  
Author Message
lgds(at)post6.tele.dk
Guest





PostPosted: Wed Mar 25, 2009 8:41 am    Post subject: Woodcomp Propellers Reply with quote

Thank you very much for the information, David.
Regards Gert
OY-GDS


Den 25/03/2009 kl. 16.41 skrev David Joyce:

Quote:
I am slightly reluctant to restart this thread, but Woodcomp have
just sent me a list of comments and corrections to some of the
statements produced in the last two weeks:
1) All Woodcomp VP props have mechanical stops as well as electrical
stops. For normal props these mechanical stops are at the fine &
course limits, but for reversible props a fine limit mechanical stop
is not possible. Instead there is a mechanical stop at the end of
the reverse range, and similar arrangements apply to the feathering
prop.
2) The electric motor of the SR3000 is supplied by Bosch and rated
at 12 volts
3) The microswitches are manufactured by Matsuschita and are rated
at 16 amps and the diodes are rated at 5 amps. The usual working
current through the motor is 4-5amps, but this current only flows
through the diodes for 0.2-=0.3 secs
4) The microswitches at the fine pitch stop are connected in series
and activating either one cuts the current through the normal range
circuit operating through the outer and middle rings. They state
that the only way to overwhelm the fine stop system and to proceed
to superfine pitch is to apply a voltage to the reverse system,
operating through the outer and inner pick up rings, and they do not
know of any mechanical or electrical failure in their systems which
could cause this.
I have no financial interest in Woodcomp, but as the first
person to get a Woodcomp prop accepted by the PFA, have become
someone they talk to in the UK!
Regards, David Joyce, G-XSDJ


- The Matronics Europa-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Europa-List
Back to top
frans(at)paardnatuurlijk.
Guest





PostPosted: Wed Mar 25, 2009 9:20 am    Post subject: Woodcomp Propellers Reply with quote

David Joyce wrote:
Quote:
I am slightly reluctant to restart this thread, but Woodcomp have just
sent me a list of comments and corrections to some of the statements
produced in the last two weeks:

Thanks for your confirmation. It is very much similar to what I
expected. Interesting to see that they came to the same conclusion: the
only thing that could have caused it is a voltage applied to the third
reverse ring.

Something else, I'm hesistating between a 2-blade and 3-blade Woodcomp
3000/W prop.
Main pro's of the 2-blade are the significant weight savings of about
4Kg's (8-9 lbs), and the better cruise parameters (faster). I know that
the climb parameters are slightly less, but I try to optimize for
cruising as I feel that a 914 with intercooler will probably climb fast
enough anyway. For taking off from a short strip I have to land there
first, so if the take-off length is less or equal to the required
landing lenght it is fine by me.
As most folks here are choosing for a 3-blade prop, I'm wondering why
that is? Visiual appearance, or are there things I just didn't see?
I know about this vibration thing, but have confidence that it can be
largely tuned away with balancing the carbs and blades. Many commercial
airplanes with Rotax 914's are flying with 2-blade props, so it is
apparently acceptable to do so.

How much ground clearance is recommended for a tri-gear operating on a
grass strip?

With a nose-wheel mod (thanks Karl!), I will get about 300mm clearance
if I choose for a 1720mm (67.5") prop. I guess this is acceptable?

--
Frans Veldman


- The Matronics Europa-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Europa-List
Back to top
john.heykoop(at)googlemai
Guest





PostPosted: Wed Mar 25, 2009 11:29 am    Post subject: Woodcomp Propellers Reply with quote

Frans
 
I was told by Andy Draper that I would have to demonstrate compliance with CS-VLA925 if I wanted to fit a propeller with a diameter of more than 64" to my Europa XS monowheel.
 
He said I would have to be able to demonstrate a minimum ground clearance of 230mm, with the aircraft fully loaded, in a level attitude and with a flat tyre.
 
I chickened out at that point and bought an Airmaster CS propeller.
 
John Heykoop
G-JHKP
On Wed, Mar 25, 2009 at 5:00 PM, Frans Veldman <frans(at)paardnatuurlijk.nl (frans(at)paardnatuurlijk.nl)> wrote:
[quote] --> Europa-List message posted by: Frans Veldman <frans(at)paardnatuurlijk.nl (frans(at)paardnatuurlijk.nl)>
David Joyce wrote:
Quote:
I am slightly reluctant to restart this thread, but Woodcomp have just
> sent me a list of comments and corrections to some of the statements

Quote:
produced in the last two weeks:

Thanks for your confirmation. It is very much similar to what I
expected. Interesting to see that they came to the same conclusion: the
only thing that could have caused it is a voltage applied to the third
reverse ring.

Something else, I'm hesistating between a 2-blade and 3-blade Woodcomp
3000/W prop.
Main pro's of the 2-blade are the significant weight savings of about
4Kg's (8-9 lbs), and the better cruise parameters (faster). I know that
the climb parameters are slightly less, but I try to optimize for
cruising as I feel that a 914 with intercooler will probably climb fast
enough anyway. For taking off from a short strip I have to land there
first, so if the take-off length is less or equal to the required
landing lenght it is fine by me.
As most folks here are choosing for a 3-blade prop, I'm wondering why
that is? Visiual appearance, or are there things I just didn't see?
I know about this vibration thing, but have confidence that it can be
largely tuned away with balancing the carbs and blades. Many commercial
airplanes with Rotax 914's are flying with 2-blade props, so it is
apparently acceptable to do so.

How much ground clearance is recommended for a tri-gear operating on a
grass strip?

With a nose-wheel mod (thanks Karl!), I will get about 300mm clearance
if I choose for a 1720mm (67.5") prop. I guess this is acceptable?

--
Frans Veldman

ist Un/Subscription,
www.matronics.com/Navigator?Europa-List" target="_blank">http://www.matronics.com/Navigator?Europa-List
ronics.com/" target="_blank">http://forums.matronics.com
Matt Dralle, List Admin.
=====

[b]


- The Matronics Europa-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Europa-List
Back to top
josok-e(at)ukolo.fi
Guest





PostPosted: Wed Mar 25, 2009 11:29 am    Post subject: Woodcomp Propellers Reply with quote

David and All,

Probably i am the only one who has ever opened an SR 3000 hub. There are no mechanical endstops. Not on the end of any travel movements. Maybe added later, that i don't know.

The micro switches are not suitable for outdoor use. That point is left out.

The rating of the micro switches, if 16A? is probably for AC. DC ratings are usually 1/4 to 1/3 of that. Left out. Why two in series? Doubt about the quality? Left out.

If the normal working current range of the motor is 4 A, the stall current, or startup current, is about 5 times higher. That stall current, startup current probably is over 20 A for a very short period. Specifications of diodes are for peak currents too. Peak current, even glitches break semiconductors. So any time the (fine) endstop micro switches are opened, the reverse current, momentarely up to 20 A will fry a 5 A diode easily. Left out.

If the diode is short circuited, there is no electrical endstop working. If there would be a mechanical endstop, the motor could fry because it would be blocked. Left out.

So David, please ask some more questions? I do very well understand, that you are not an outsider, as the person who got the first SR 3000 approved by the PFA. I am not either, so that could balance things out. Your interest seems to be to flatten issues with the Woodcomp SR3000, mine is to warn about the product, and maybe save lifes.

Regards,

Jos Okhuijsen
Visit - www.EuropaOwners.org


- The Matronics Europa-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Europa-List
Back to top
josok-e(at)ukolo.fi
Guest





PostPosted: Wed Mar 25, 2009 11:59 am    Post subject: Woodcomp Propellers Reply with quote

Just to bury the 3rd ring-reverse power nonsense once and for all:
If there would have been power on the 3rd ring, the controller, which also was engaged would have tried to increase pitch. Which would have caused a full short circuit. With the result that the cb would have cut in at the very same moment. The pitch would have been reduced, minimally, and i still would have had a very flyable airplane.

I must admit, that "reverse" error was the first thing that popped up in my head while still flying the plane, but simple looking at the facts was rejected as impossible later.

Regards,

Jos Okhuijsen
Visit - www.EuropaOwners.org


- The Matronics Europa-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Europa-List
Back to top
frans(at)paardnatuurlijk.
Guest





PostPosted: Wed Mar 25, 2009 12:37 pm    Post subject: Woodcomp Propellers Reply with quote

John Heykoop wrote:

Quote:
I was told by Andy Draper that I would have to demonstrate compliance with
CS-VLA925 if I wanted to fit a propeller with a diameter of more than 64" to
my Europa XS monowheel.

He said I would have to be able to demonstrate a minimum ground clearance of
230mm, with the aircraft fully loaded, in a level attitude and with a flat
tyre.

I don't have to show compliance here, but this requirement is a good
indication. I guess that I will be allright with my 300mm clearance,
with an inflated tyre. Thanks!

--
Frans Veldman


- The Matronics Europa-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Europa-List
Back to top
frans(at)paardnatuurlijk.
Guest





PostPosted: Wed Mar 25, 2009 12:59 pm    Post subject: Woodcomp Propellers Reply with quote

josok wrote:
Quote:


Just to bury the 3rd ring-reverse power nonsense once and for all: If
there would have been power on the 3rd ring, the controller, which
also was engaged would have tried to increase pitch. Which would have
caused a full short circuit. With the result that the cb would have
cut in at the very same moment. The pitch would have been reduced,
minimally, and i still would have had a very flyable airplane.

Unless, of course, a relay, powered by the reverse circuitry,
automatically switched mode as well. Wink

I can't see what could have happened without a diagram. The 3rd ring
reverse power thing is so far the most reasonable explanation, for the
other things (like failed micro-switches, failed diodes, and more of
that good stuff) you still have the problem that something was putting
out power to the prop, while the RPM was already way above the target
value. True that a failed micro switch or diode can allow this to
happen, but they can not cause this to happen, they can not put power on
the system by themselves, unless something is putting out power to them.
In the scenario of failed switches you also have to bring in a failed
controller at the same time, still providing power while the prop was
already over the limit. You can't get rid of this multiple-failure
scenario, and that is, like we all know, a scenario which is the least
unlikely. At least, this would imply that Smart Avionics is as "guilty"
as Woodcomp, and failed at the same time as the micro-switches. I
haven't heard you about Smart Avionics yet.

About the lack of mechanical endstops, someone has sent pictures of the
inside of the Woodcomp propeller, with the mechanical endstops clearly
visible.
But true, if the prop has to be able to go to reverse, you can't have
the endstops.
You'd better warn people not to install reverse systems.

Look here, I can understand that this is a sensitive topic for you. But
I guess the reason of this discussion is and remains to find out whether
the failure occured can happen to anyone because it is a design flaw, or
that it most likely happend by a combination (perhaps) of a failure in a
home brew safety bypass system and the fact that the propeller system
was able to go to fine pitch anyway because of the reverse option.
With other words: without reverse, Woodcomp's are safe propellers.

--
Frans Veldman


- The Matronics Europa-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Europa-List
Back to top
rparigor(at)suffolk.lib.n
Guest





PostPosted: Wed Mar 25, 2009 3:40 pm    Post subject: Woodcomp Propellers Reply with quote

All this talk about propellors reversing.I fly a fairly high performance model flying wing glider I slope with. When it is soarable it is very hard to land because when you dive you gain tremendous speed. I fitted a small electric motor with a folding prop and a car speed controller that is reversable. On a flying wing almost anything you do to drag things up changes pitch, that is except putting motor into reverse. Boy does that drag things up.A nagging question I have had with flying with a reversable prop was would it not be prudent to go up to altitude and fool with putting it into reverse and also very fine flat pitch to recognize reaction of aeroplane, and if it were to occur uncommanded, turn off motor which would turn you into a reasonable glider instead of a lead sled?My DAR was test flying a RV, and throttle stuck at 1600 RPM on crosswind, he ate up half the runway when it became apparent had he shut off motor right away, landing would have been uneventful instead of crash.Just another story, I was talking with a high time instructor who was giving a student last flight before IFR checkride. Motor at a few hundred feet with plenty of runway ahead, but plane stalled and spun in? Ended up crank broke right behind main bearing and prop began to freewheel. He said he was pointing down much steepier than normal but plane stalled because of horendous drag created by big disc up front.For those who have not first hand experiance, next time you get hold of a pinwheel, hold it out car window at 30mph with pinwheel held captive. Not too much drag. Let it spin up--- WOW an amazing amount of drag. Prop going into reverse is not much worst than freewheeling prop BTWRon Parigoris [quote][b]

- The Matronics Europa-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Europa-List
Back to top
kheindl(at)msn.com
Guest





PostPosted: Wed Mar 25, 2009 4:12 pm    Post subject: Woodcomp Propellers Reply with quote

 
Ron C
 
If that is so C would you agree that a feathering option just for such an emergency would be a good idea ? I understand that the gliding distance is greatly increased.
 
Karl


 
Date: Wed C 25 Mar 2009 19:29:04 -0400
Subject: Re: Woodcomp Propellers
From: rparigor(at)suffolk.lib.ny.us
To: europa-list(at)matronics.com

All this talk about propellors reversing.

I fly a fairly high performance model flying wing glider I slope with. When it is soarable it is very hard to land because when you dive you gain tremendous speed. 

I fitted a small electric motor with a folding prop and a car speed controller that is reversable. 

On a flying wing almost anything you do to drag things up changes pitch C that is except putting motor into reverse. Boy does that drag things up.

A nagging question I have had with flying with a reversable prop was would it not be prudent to go up to altitude and fool with putting it into reverse and also very fine flat pitch to recognize reaction of aeroplane C and if it were to occur uncommanded C turn off motor which would turn you into a reasonable glider instead of a lead sled?

My DAR was test flying a RV C and throttle stuck at 1600 RPM on crosswind C he ate up half the runway when it became apparent had he shut off motor right away C landing would have been uneventful instead of crash.

Just another story C I was talking with a high time instructor who was giving a student last flight before IFR checkride. Motor at a few hundred feet with plenty of runway ahead C but plane stalled and spun in? Ended up crank broke right behind main bearing and prop began to freewheel. He said he was pointing down much steepier than normal but plane stalled because of horendous drag created by big disc up front.

For those who have not first hand experiance C next time you get hold of a pinwheel C hold it out car window at 30mph with pinwheel held captive. Not too much drag. Let it spin up--- WOW an amazing amount of drag. Prop going into reverse is not much worst than freewheeling prop BTW
Ron Parigoris

[quote]

Quote:
http://www.matronics.com/Navigator?Europa-List
ronics.com

ww.matronics.com/contribution

[b]


- The Matronics Europa-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Europa-List
Back to top
kheindl(at)msn.com
Guest





PostPosted: Wed Mar 25, 2009 4:22 pm    Post subject: Woodcomp Propellers Reply with quote

Josok C
 
It may be that not all Woodcomps meet the same safety specs and quality control. Yours didn't have end switches. Is it not possible to confirm this from the wreck ?
Dave Miller had endless problems with his SR2000 C paid a fortune in shipping and 'repair' costs C and ended up throwing it away. Support was hopeless.
Can anyone xplain why two motors failed after a few hours C or can anyone tell me what the rpm limit is for these motors C which are stamped with the name Johnson ?
 
Karl



 
[quote] Subject: Re: Woodcomp Propellers
From: josok-e(at)ukolo.fi
Date: Wed C 25 Mar 2009 21:45:08 +0200
To: europa-list(at)matronics.com

--> Europa-List message posted by: "josok" <josok-e(at)ukolo.fi>

Just to bury the 3rd ring-reverse power nonsense once and for all:
If there would have been power on the 3rd ring C the controller C which also was engaged would have tried to increase pitch. Which would have caused a full short circuit. With the result that the cb would have cut in at the very same moment. The pitch would have been reduced C minimally C and i still would have had a very flyable airplane.

I must admit C that "reverse" error was the first thing that popped up in my head while still flying the plane C but simple looking at the facts was rejected as impossible later.

Regards C

Jos Okhuijsen






Visit - www.EuropaOwners.org

>


Quote:
[b]


- The Matronics Europa-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Europa-List
Back to top
rparigor(at)suffolk.lib.n
Guest





PostPosted: Wed Mar 25, 2009 5:49 pm    Post subject: Woodcomp Propellers Reply with quote

Hi KarlIn a failure mode where prop stuck itself in fine or reverse, a feathering feature would do you no good at all, the prop is stuck.If your engine quits, stopping prop helps to extend glide and feathering prop helps even more to extend glide.Ron Parigoris [quote][b]

- The Matronics Europa-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Europa-List
Back to top
DuaneFamly(at)aol.com
Guest





PostPosted: Wed Mar 25, 2009 8:28 pm    Post subject: Woodcomp Propellers Reply with quote

Could someone with a wiring diagram for the hub and controller please supply it to the list so those with the knowledge could look at it and make some educated remarks? I think that a person's preference for a particular product should stand up to scrutiny by their fellow builders/flyers. Make a list of the pros and cons so that everyone can decide what points are relevant to them in particular. By everyone keeping a thick skin and not taking personal affronts towards questions, comments, and points of view, we, as a group, can help the whole make a damned good decision.

Do Not Archive.
Mike Duane A207A
Redding, California
XS Conventional Gear
Jabiru 3300A
Sensenich R64Z N
Ground Adjustable Prop

Feeling the pinch at the grocery store? Make dinner for $10 or less.
[quote][b]


- The Matronics Europa-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Europa-List
Back to top
davidjoyce(at)doctors.org
Guest





PostPosted: Thu Mar 26, 2009 8:44 am    Post subject: Woodcomp Propellers Reply with quote

Jos I suspect you had your mind on other things! Carl Pattinson has been
requested by the LAA to modify the mechanical end stop of his prop to stop
it being able to go into reverse. He has the prop from William Mills
aircraft, which happens not to have been on William's plane when he crashed.
It is one of the earliest SR3000s. Carl has recently dismantled it and the
mechanical end stop is there, taking the form of a stud sliding in a
groove, with the length of the groove determining the mechanically possible
pitch range.
Regards, David Joyce, G-XSDJ
---


- The Matronics Europa-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Europa-List
Back to top
Display posts from previous:   
Post new topic   Reply to topic    Matronics Email Lists Forum Index -> Europa-List All times are GMT - 8 Hours
Goto page Previous  1, 2
Page 2 of 2

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


Powered by phpBB © 2001, 2005 phpBB Group