Today's Message Index:
----------------------
1. 12:51 AM - Re: Thrust - Over Rated (Michael Gibbs)
2. 01:52 AM - SV: Tundra tyres. (Michel Verheughe)
3. 03:50 AM - Re: [Off-topic] English (Michel Verheughe)
4. 03:59 AM - Re: Thrust - Over Rated (Michel Verheughe)
5. 06:23 AM - Re: Tundra tyres. (skyflyte@comcast.net)
6. 06:26 AM - Painting Templates (Colin Durey)
7. 06:36 AM - Re: Thrust - Over Rated? (Lowell Fitt)
8. 07:08 AM - Re: Re: Thrust - Over Rated (Lowell Fitt)
9. 07:29 AM - Re: Re: Thrust - Over Rated (wingsdown)
10. 07:29 AM - Re: Re: Thrust - Over Rated (alnanarthur)
11. 08:27 AM - Re: Re: Thrust - Over Rated (Algate)
12. 08:39 AM - Re: Re: Thrust - Over Rated (ron schick)
13. 08:48 AM - Re: Tundra tyres. (Rex)
14. 09:26 AM - Re: Thrust - Over Rated? (Randy Daughenbaugh)
15. 12:51 PM - (kenneth schooley)
16. 12:51 PM - Re: Thrust - Over Rated? (ron schick)
17. 03:25 PM - Re: Re: Thrust - Over Rated (John Anderson)
18. 03:25 PM - Re: SV: Tundra tyres. (kurt schrader)
19. 05:38 PM - Re: Re: Thrust - Over Rated (kurt schrader)
20. 05:50 PM - Re: Re: Thrust - Over Rated (kurt schrader)
21. 06:55 PM - 912S/ oil cooler efficiency (Fred Shiple)
22. 06:55 PM - Thrust...Overrated? (Clem Nichols)
23. 07:26 PM - Re: 912S/ oil cooler efficiency (John King)
24. 08:22 PM - Re: Re: Thrust - Over Rated (John Anderson)
25. 08:23 PM - Re: 912S/ oil cooler efficiency (Fred Shiple)
26. 08:30 PM - Re: Elevator hinge tab question?? (darinh)
Message 1
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| Subject: | Re: Thrust - Over Rated |
--> Kitfox-List message posted by: Michael Gibbs <MichaelGibbs@cox.net>
Randy sez:
>In short, if you want more thrust, all you have to do is sacrifice
>top speed. Therefore, thrust is irrelevant.
If you want more thrust AND more top speed, you get an in-flight
adjustable prop. You wouldn't drive your car in one gear all the
time, why operate your airplane that way?
Mike G.
N728KF
Message 2
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--> Kitfox-List message posted by: Michel Verheughe <michel@online.no>
From: kurt schrader [smokey_bear_40220@yahoo.com]
> Have you seen any crop circles lately? ;-)
Yes, concentric circles about the size of the distance between the main gears of
a B-767 and your name was all over it! The Norwegian authorities are being informed!
:-)
> I had a tire on my van where the tread looked fine, but seperated internally
and
> got a big flat spot.
That could have happened to me too. I'll need to look at it. But, Ron and Kurt,
here a good analogy: If you press hard with your thumb on the fabric of your
wing, you'll make a hollow that will come back to normal after a time and/or with
the help of heat.
Well, my tyres are exactly the same, except that they don't seem to come back to
the normal smooth and round shape. Since there is nothing visible on the outside,
maybe there is something damaged on the inside. But I can't imagine what,
when I look at the inside of the old tyres. What do you think?
Cheers,
Michel
Message 3
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| Subject: | [Off-topic] English |
--> Kitfox-List message posted by: Michel Verheughe <michel@online.no>
> From: Lowell Fitt [lcfitt@sbcglobal.net]
> Sorry to say this, but manover gets the underline treatment. My dictionary
> insists on maneuver as the cerect spellin.
Sorry, my mistake, Lowell, I tried too hard to make it American-as-it-sounds-like!
:-)
I'd just like to add a wee bit here: the reason I use a speller, read Time and
try to write proper English is that, for many years now, I have to write brochures
in English, for the international maritime marked. The funny thing is that
I write English better than Norwegian, the country where I have lived for the
past 30 years. It proves one thing: once you put your mind to do something well,
... it gets better with time. Oh, just another precision: In Belgium and
Norway (probably other too), the English we learn at school is British English.
I guess it's like when you learn Spanish in the US, you don't learn Mexican
but Castilian, the language spoken by the people of Castilla in Spain.
Cheers,
Michel
do not archive
Message 4
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| Subject: | Re: Thrust - Over Rated |
--> Kitfox-List message posted by: Michel Verheughe <michel@online.no>
> From: Michael Gibbs [MichaelGibbs@cox.net]
> You wouldn't drive your car in one gear all the
> time, why operate your airplane that way?
Well ... yes, when you have a Jabiru engine that doesn't like much more than a
solid wooded prop, Mike! :-) But, as I have said before, I love the idea of an
in-flight adjustable prop ever since my father put a adjustable pitch prop on
our sailboat when I was a child.
In-flight adjustable pitch is my wet dream ... well, my second wet dream! :-)
Cheers,
Michel
do not archive
Message 5
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| Subject: | Re: Tundra tyres. |
--> Kitfox-List message posted by: skyflyte@comcast.net
I have lumpy looking tires like that too! Mine are caused by the inner tube, which
can fold over on itself due to the low inflation pressure. After I found
out the cause, I quit worrying about it.
-------------- Original message --------------
From: Michel Verheughe <michel@online.no>
> --> Kitfox-List message posted by: Michel Verheughe
>
> On May 7, 2006, at 6:38 PM, kurt schrader wrote:
> > Hummm. Some tires still show a seam where the belt wrap joins.
>
> This is not the case, Kurt. Please look at these photos I took today:
>
> http://home.online.no/~michel/tmp/Tyres.jpg
>
> On the two upper photos, you can see, in the red circle, the
> depressions in the tyres. On the lower photo, the steel rail that may
> be the cause of the depressions. It's the only thing I can think of.
> Strange, isn't it? Also note that the hangar (actually an old workshop
> for the airfield) is not wide enough to get my Kitfox in and out
> straight. When over the rail, I have to turn the plane 180 degrees to
> get one wing out at the time.
>
> Cheers,
> Michel
>
>
>
>
>
>
>
>
>
>
>
>
>
<html><body>
<DIV>I have lumpy looking tires like that too! Mine are caused by the inner
tube, which can fold over on itself due to the low inflation pressure.
After I found out the cause, I quit worrying about it.</DIV>
<DIV> </DIV>
<BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px solid">-------------- Original message -------------- <BR>From: Michel Verheughe <michel@online.no> <BR><BR>> --> Kitfox-List message posted by: Michel Verheughe <MICHEL@ONLINE.NO><BR>> <BR>> On May 7, 2006, at 6:38 PM, kurt schrader wrote: <BR>> > Hummm. Some tires still show a seam where the belt wrap joins. <BR>> <BR>> This is not the case, Kurt. Please look at these photos I took today: <BR>> <BR>> http://home.online.no/~michel/tmp/Tyres.jpg <BR>> <BR>> On the two upper photos, you can see, in the red circle, the <BR>> depressions in the tyres. On the lower photo, the steel rail that may <BR>> be the cause of the depressions. It's the only thing I can think of. <BR>> Strange, isn't it? Also note that the hangar (actually an old workshop <BR>> for the airfield) is not wide enough to get my Kitfox in and out <BR>> straight. When over the
rail,
us sup
Message 6
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| Subject: | Painting Templates |
--> Kitfox-List message posted by: "Colin Durey" <colin@ptclhk.com>
Hi folks,
I'm starting to plan the colour scheme for my (our) KF IV - I'm in a
syndicate of 3. We are trying to get the decision process rolling for
choosing colours and layout, as it will only be a few weeks before we put
the fabric on, and will then need to be ready to paint.
Some time back, either on this list, or one of the Kitfox sites, I saw
reference to painting templates for the KF IV. They appeared to be side
view line drawings. Does anyone know of these, and where they can be
found?
Regards
Colin Durey
Sydney
+61-418-677073 (M)
+61-2-945466162 (F)
Message 7
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| Subject: | Re: Thrust - Over Rated? |
--> Kitfox-List message posted by: "Lowell Fitt" <lcfitt@sbcglobal.net>
Error Message, Regarding the Powerfin, one went to the Ivo, not the Warp
and I am not sure he is happy with it.
Lowell
----- Original Message -----
From: "Lowell Fitt" <lcfitt@sbcglobal.net>
Sent: Monday, May 08, 2006 7:58 PM
Subject: Re: Kitfox-List: Thrust - Over Rated?
> --> Kitfox-List message posted by: "Lowell Fitt" <lcfitt@sbcglobal.net>
>
> Randy,
>
> No flames here. I have two friends that went to the PowerFin. They had
> the
> exact issues you had and eventually went to the shortened blades. They
> got
> the improvements you did. One is now with the Warp and doesn't know if he
> likes it. I think the other still has the Powerfin. They'll both be at
> the
> Cameron Park fly-in.
>
> I guess that is what the poor man's dyno was all about - finding the HP at
> the prop.
>
> Lowell
> ----- Original Message -----
> From: "Randy Daughenbaugh" <rjdaugh@rapidnet.com>
> To: <kitfox-list@matronics.com>
> Sent: Monday, May 08, 2006 7:08 PM
> Subject: Kitfox-List: Thrust - Over Rated?
>
>
>> --> Kitfox-List message posted by: "Randy Daughenbaugh"
>> <rjdaugh@rapidnet.com>
>>
>> I have been seeing discussion of thrust lately and I think it is nearly
>> irrelevant.
>>
>> I have a PowerFin three blade prop on a 912S Series 5/7. When I first
>> set
>> it up, static RPM was 5800 RPM. And MAN DID IT HAVE THRUST! The
>> acceleration would make your head snap back as you pushed the throttle
>> in.
>> Well, it came time for first flight, and boy did it get off the ground
>> fast!
>> I don't have good numbers, but I am guessing about 150 feet ground roll.
>> BUT (you had to know that was coming), it would only fly about 65 - 70
>> mph
>> without over-reving the engine.
>>
>> So I put in more pitch on the prop. Got up to 85 mph. But lower static
>> rpm, less thrust and acceleration, longer ground roll. Added more
>> pitch -
>> 95 mph, and less thrust. More pitch - WOT about 108 mph - cruise at
>> 5500
>> rpm about 96 mph - static rpm about 4900 rpm. But now ground roll on
>> take
>> off approaching 500 ft. Spam can territory!
>>
>> PowerFin said they would shorten the prop 1" each blade. I finally took
>> them up on it, but it was a tough decision for me.... When I put it back
>> on
>> the plane, I added a degree and a quarter more pitch. Now I cruise at
>> 106
>> mph AND off the ground much quicker - maybe 275' solo.
>>
>> In short, if you want more thrust, all you have to do is sacrifice top
>> speed. Therefore, thrust is irrelevant.
>>
>> Indeed, it is more complicated than that. An "efficient" prop slips
>> enough
>> on take off to get the rpm up so that you can use most of your horse
>> power
>> to get off the ground, but still has enough pitch so that you can get a
>> decent top speed. My plane is "over prop'ed" with the three blade
>> PowerFin.
>> I am saving my nickels for the Sensinich ground adjustable two blade.
>>
>> I would have written this earlier but was in Montana visiting my new
>> grandson and didn't have my flame suit with me.
>>
>> Randy - Everything in aviation is a compromise.
>>
>> .
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>
>
>
Message 8
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| Subject: | Re: Thrust - Over Rated |
--> Kitfox-List message posted by: "Lowell Fitt" <lcfitt@sbcglobal.net>
Mike, I couldn't agree with you more. However there are airframe -
engine - prop combinations that will give enough of each with a fixed pitch
prop that the cost / benefit and complexity just hasn't made me even think
about yet.
In our airplanes, I think an argument could be made that a cockpit
adjustable prop is sort of like a bandade for a mismatched engine -
airframe.
Personally I like the simplicity in flight and the lack of prop maintenane
issues of the old fashioned ground adjustable Warp Drive prop. I can almost
keep up with the PowerFin in climb and cruise has never been an issue for
me, I can get plenty.
Lowell
----- Original Message -----
From: "Michael Gibbs" <MichaelGibbs@cox.net>
Sent: Tuesday, May 09, 2006 12:48 AM
Subject: Kitfox-List: Re: Thrust - Over Rated
> --> Kitfox-List message posted by: Michael Gibbs <MichaelGibbs@cox.net>
>
> Randy sez:
>
>>In short, if you want more thrust, all you have to do is sacrifice
>>top speed. Therefore, thrust is irrelevant.
>
> If you want more thrust AND more top speed, you get an in-flight
> adjustable prop. You wouldn't drive your car in one gear all the
> time, why operate your airplane that way?
>
> Mike G.
> N728KF
>
>
>
Message 9
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| Subject: | Re: Thrust - Over Rated |
--> Kitfox-List message posted by: "wingsdown" <wingsdown@comcast.net>
If you have to turn the engine as fast or nearly so for take off as for
fast flight, then an in-flight adjustable prop has merit. Even slow
turning dinosaur engines for the most part have constant speed props.
Band-Aids come in all shapes and sizes. Some are built right in and you
never see them or for that matter know they are there. And are quite
subjective as to definition.
Rick
-----Original Message-----
From: owner-kitfox-list-server@matronics.com
[mailto:owner-kitfox-list-server@matronics.com] On Behalf Of Lowell Fitt
Sent: Tuesday, May 09, 2006 7:05 AM
Subject: Re: Kitfox-List: Re: Thrust - Over Rated
--> Kitfox-List message posted by: "Lowell Fitt" <lcfitt@sbcglobal.net>
Mike, I couldn't agree with you more. However there are airframe -
engine - prop combinations that will give enough of each with a fixed
pitch
prop that the cost / benefit and complexity just hasn't made me even
think
about yet.
In our airplanes, I think an argument could be made that a cockpit
adjustable prop is sort of like a bandade for a mismatched engine -
airframe.
Personally I like the simplicity in flight and the lack of prop
maintenane
issues of the old fashioned ground adjustable Warp Drive prop. I can
almost
keep up with the PowerFin in climb and cruise has never been an issue
for
me, I can get plenty.
Lowell
----- Original Message -----
From: "Michael Gibbs" <MichaelGibbs@cox.net>
Sent: Tuesday, May 09, 2006 12:48 AM
Subject: Kitfox-List: Re: Thrust - Over Rated
> --> Kitfox-List message posted by: Michael Gibbs
> --> <MichaelGibbs@cox.net>
>
> Randy sez:
>
>>In short, if you want more thrust, all you have to do is sacrifice top
>>speed. Therefore, thrust is irrelevant.
>
> If you want more thrust AND more top speed, you get an in-flight
> adjustable prop. You wouldn't drive your car in one gear all the
> time, why operate your airplane that way?
>
> Mike G.
> N728KF
>
>
>
Message 10
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| Subject: | Re: Thrust - Over Rated |
--> Kitfox-List message posted by: alnanarthur <alnanarthur@sbcglobal.net>
Mike,
You are right, everything in life is a tradeoff.
A Harrier Jet takes off with zero ground roll and goes fast!
A ground adjustable has less parts, is more reliable and less expensive.
Also, it's allowed under the sport pilot rule.
I get off the ground in about 200 ft (solo), climb at 1200 ft/min and
cruise at 105 mph at 5200 rpm.
Allan Arthur, Sport Pilot
Kitfox 5, N40AA
Rotax 912s, Warpdrive 3 blade
Byron Airport, CA (C83) Hanger C8
On May 9, 2006, at 12:48 AM, Michael Gibbs wrote:
> --> Kitfox-List message posted by: Michael Gibbs
> <MichaelGibbs@cox.net>
>
> Randy sez:
>
>> In short, if you want more thrust, all you have to do is sacrifice
>> top speed. Therefore, thrust is irrelevant.
>
> If you want more thrust AND more top speed, you get an in-flight
> adjustable prop. You wouldn't drive your car in one gear all the
> time, why operate your airplane that way?
>
> Mike G.
> N728KF
>
>
Message 11
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| Subject: | Re: Thrust - Over Rated |
--> Kitfox-List message posted by: "Algate" <algate@attglobal.net>
I don't know that IFA props could be considered bandaids. No matter how well
matched your engine may be to the airframe it is always a compromise to
every other set of circumstances other than the ideal situation the
combination has been "tuned" for. The IFA prop allows the "tuning" for a
wide range of variable conditions.
I'm sure that when you have a fixed or ground adjustable prop there might be
the time you would like the flexibility of a IFA prop ie. When you have
landed on a small lake a long way from home (so you have max fuel) and you
catch a serious number of large fish. All of a sudden the shore line looks a
lot closer and the thought of an additional 300ft/min climb looks pretty
inviting.
Likewise there are times when it's really convenient to be able to maintain
airspeed, lower fuel consumption and noise by simply flicking a switch.
I think sometimes simplicity can be a state of mind that comes with being
comfortable with a technology - I guess even an electric light bulb looked
pretty daunting when it was first introduced.
No flame intended!
GaryA
Lite2
-----Original Message-----
From: owner-kitfox-list-server@matronics.com
[mailto:owner-kitfox-list-server@matronics.com] On Behalf Of Lowell Fitt
Sent: Tuesday, May 09, 2006 10:05 AM
Subject: Re: Kitfox-List: Re: Thrust - Over Rated
--> Kitfox-List message posted by: "Lowell Fitt" <lcfitt@sbcglobal.net>
Mike, I couldn't agree with you more. However there are airframe -
engine - prop combinations that will give enough of each with a fixed pitch
prop that the cost / benefit and complexity just hasn't made me even think
about yet.
In our airplanes, I think an argument could be made that a cockpit
adjustable prop is sort of like a bandade for a mismatched engine -
airframe.
Personally I like the simplicity in flight and the lack of prop maintenane
issues of the old fashioned ground adjustable Warp Drive prop. I can almost
keep up with the PowerFin in climb and cruise has never been an issue for
me, I can get plenty.
Lowell
----- Original Message -----
From: "Michael Gibbs" <MichaelGibbs@cox.net>
Sent: Tuesday, May 09, 2006 12:48 AM
Subject: Kitfox-List: Re: Thrust - Over Rated
> --> Kitfox-List message posted by: Michael Gibbs <MichaelGibbs@cox.net>
>
> Randy sez:
>
>>In short, if you want more thrust, all you have to do is sacrifice
>>top speed. Therefore, thrust is irrelevant.
>
> If you want more thrust AND more top speed, you get an in-flight
> adjustable prop. You wouldn't drive your car in one gear all the
> time, why operate your airplane that way?
>
> Mike G.
> N728KF
>
>
>
Message 12
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| Subject: | Re: Thrust - Over Rated |
--> Kitfox-List message posted by: "ron schick" <roncarolnikko@hotmail.com>
Hi Alan Yes thrust is a variable with pich and length of prop. The VW's
have been limited to small slippery airplanes due to the fact they have to
swing a small prop in order to get in the power band. My goal is to use a
redrive that allows a large prop suitable for the Kitfox performance range.
Ron NB Ore
>From: alnanarthur <alnanarthur@sbcglobal.net>
>To: kitfox-list@matronics.com
>Subject: Re: Kitfox-List: Re: Thrust - Over Rated
>Date: Tue, 9 May 2006 07:28:14 -0700
>
>--> Kitfox-List message posted by: alnanarthur <alnanarthur@sbcglobal.net>
>
>Mike,
>
>You are right, everything in life is a tradeoff.
>
>A Harrier Jet takes off with zero ground roll and goes fast!
>
>A ground adjustable has less parts, is more reliable and less expensive.
>Also, it's allowed under the sport pilot rule.
>
>I get off the ground in about 200 ft (solo), climb at 1200 ft/min and
>cruise at 105 mph at 5200 rpm.
>
>
>Allan Arthur, Sport Pilot
>Kitfox 5, N40AA
>Rotax 912s, Warpdrive 3 blade
>Byron Airport, CA (C83) Hanger C8
>
>
>On May 9, 2006, at 12:48 AM, Michael Gibbs wrote:
>
> > --> Kitfox-List message posted by: Michael Gibbs
> > <MichaelGibbs@cox.net>
> >
> > Randy sez:
> >
> >> In short, if you want more thrust, all you have to do is sacrifice
> >> top speed. Therefore, thrust is irrelevant.
> >
> > If you want more thrust AND more top speed, you get an in-flight
> > adjustable prop. You wouldn't drive your car in one gear all the
> > time, why operate your airplane that way?
> >
> > Mike G.
> > N728KF
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
>
>
_________________________________________________________________
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Message 13
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| Subject: | Re: Tundra tyres. |
--> Kitfox-List message posted by: Rex <gypsybee@copper.net>
Michel, As "skyflyte" suggests, if a tube fold is determined to be the
cause of the flat spots, I believe the fold can be relieved with talcum
powder during assembly and careful inflation technique. I know that
inflating a tubed tire with the valve core out and letting it deflate at
least once is a good practice to allow the tube to align itself inside
the assembled rim and tire. Talcum powder (or the like) is required as
an aid. This also can reduce valve stem stress if a tire were to rotate
on the rim from the sudden rotational forces seen at landings.
(especially if brakes are inadvertently applied during touchdown).
I did a little Googling and here are some links of interest:
http://www.aeroinstock.com/pdf/SpecMountTire.pdf
http://www.planeandpilotmag.com/content/2004/sept/just_tires.html
http://www.desser.com/tech/tiremount.html
http://www.sheldonbrown.com/brandt/talcum.html
I have never changed an aircraft or ATV tire, but have lots of
experience with automobile, motorcycle and bicycle tires and tubes. It
is common to see tires rotate and cause valve stem stress on dirt bikes
and bicyces where low air pressures are used. Also be aware that extreme
valve stem stress could result in an air leak. Talcum powder can prevent
the tube from sticking to the tire if it were to rotate on the rim.
Rex
Florida
skyflyte@comcast.net wrote:
>--> Kitfox-List message posted by: skyflyte@comcast.net
>
>I have lumpy looking tires like that too! Mine are caused by the inner tube,
which can fold over on itself due to the low inflation pressure. After I found
out the cause, I quit worrying about it.
>
>
>
Message 14
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| Subject: | Thrust - Over Rated? |
--> Kitfox-List message posted by: "Randy Daughenbaugh" <rjdaugh@rapidnet.com>
I guess my main message is that to get the use of your horse power, you need
rpm's. Horse power is rpm x torque. If your prop doesn't slip on take off
and you have so much pitch in your prop that you can't get the rpm's up, you
are not going to get good take off performance and good cruise at the same
time.
Mike Gibb's point about the variable pitch prop is right on, but I want to
keep my plane LSA compliant. I seem to be getting older and want to fly a
long time yet. Some props are more efficient than others. I am still
looking.
Randy
.
-----Original Message-----
From: owner-kitfox-list-server@matronics.com
[mailto:owner-kitfox-list-server@matronics.com] On Behalf Of Lowell Fitt
Sent: Monday, May 08, 2006 8:58 PM
Subject: Re: Kitfox-List: Thrust - Over Rated?
--> Kitfox-List message posted by: "Lowell Fitt" <lcfitt@sbcglobal.net>
Randy,
No flames here. I have two friends that went to the PowerFin. They had the
exact issues you had and eventually went to the shortened blades. They got
the improvements you did. One is now with the Warp and doesn't know if he
likes it. I think the other still has the Powerfin. They'll both be at the
Cameron Park fly-in.
I guess that is what the poor man's dyno was all about - finding the HP at
the prop.
Lowell
----- Original Message -----
From: "Randy Daughenbaugh" <rjdaugh@rapidnet.com>
Sent: Monday, May 08, 2006 7:08 PM
Subject: Kitfox-List: Thrust - Over Rated?
> --> Kitfox-List message posted by: "Randy Daughenbaugh"
> <rjdaugh@rapidnet.com>
>
> I have been seeing discussion of thrust lately and I think it is nearly
> irrelevant.
>
> I have a PowerFin three blade prop on a 912S Series 5/7. When I first set
> it up, static RPM was 5800 RPM. And MAN DID IT HAVE THRUST! The
> acceleration would make your head snap back as you pushed the throttle in.
> Well, it came time for first flight, and boy did it get off the ground
> fast!
> I don't have good numbers, but I am guessing about 150 feet ground roll.
> BUT (you had to know that was coming), it would only fly about 65 - 70 mph
> without over-reving the engine.
>
> So I put in more pitch on the prop. Got up to 85 mph. But lower static
> rpm, less thrust and acceleration, longer ground roll. Added more pitch -
> 95 mph, and less thrust. More pitch - WOT about 108 mph - cruise at 5500
> rpm about 96 mph - static rpm about 4900 rpm. But now ground roll on take
> off approaching 500 ft. Spam can territory!
>
> PowerFin said they would shorten the prop 1" each blade. I finally took
> them up on it, but it was a tough decision for me.... When I put it back
> on
> the plane, I added a degree and a quarter more pitch. Now I cruise at 106
> mph AND off the ground much quicker - maybe 275' solo.
>
> In short, if you want more thrust, all you have to do is sacrifice top
> speed. Therefore, thrust is irrelevant.
>
> Indeed, it is more complicated than that. An "efficient" prop slips
> enough
> on take off to get the rpm up so that you can use most of your horse power
> to get off the ground, but still has enough pitch so that you can get a
> decent top speed. My plane is "over prop'ed" with the three blade
> PowerFin.
> I am saving my nickels for the Sensinich ground adjustable two blade.
>
> I would have written this earlier but was in Montana visiting my new
> grandson and didn't have my flame suit with me.
>
> Randy - Everything in aviation is a compromise.
>
> .
>
>
>
Message 15
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--> Kitfox-List message posted by: "kenneth schooley" <klschooley@hotmail.com>
I have decided to sell my Kitfox 7-A kit. It is approx. 50% built for less
than the kit cost originally. Located in San Diego area, but can arrange low
cost shipping. 760-728-2450
Message 16
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| Subject: | Thrust - Over Rated? |
--> Kitfox-List message posted by: "ron schick" <roncarolnikko@hotmail.com>
Yes Randy That is excactly the situation I am exploring. To get VW
horsepower you need 3600 rpm. To pull a Kitfox you should have a 68" or
more prop. To stay less than .8 mach at the tip of the prop requires a
redrive. I have an ifa prop, but will not use it on my AW cert for sport
applicability. This means finding the best combination of length and pitch
to give a climb and cruise compromise.
The VW direct drive has been critisized by some as lasy on climbout. For
that reason I am concerned about thrust. Some think I should be concerned
about using the VW. Don't worry I have flameproof shorts on so flame on.
Ron NB Or
>From: "Randy Daughenbaugh" <rjdaugh@rapidnet.com>
>To: <kitfox-list@matronics.com>
>Subject: RE: Kitfox-List: Thrust - Over Rated?
>Date: Tue, 9 May 2006 10:24:28 -0600
>
>--> Kitfox-List message posted by: "Randy Daughenbaugh"
><rjdaugh@rapidnet.com>
>
>I guess my main message is that to get the use of your horse power, you
>need
>rpm's. Horse power is rpm x torque. If your prop doesn't slip on take off
>and you have so much pitch in your prop that you can't get the rpm's up,
>you
>are not going to get good take off performance and good cruise at the same
>time.
>
>Mike Gibb's point about the variable pitch prop is right on, but I want to
>keep my plane LSA compliant. I seem to be getting older and want to fly a
>long time yet. Some props are more efficient than others. I am still
>looking.
>
>Randy
>
>.
>
>
>-----Original Message-----
>From: owner-kitfox-list-server@matronics.com
>[mailto:owner-kitfox-list-server@matronics.com] On Behalf Of Lowell Fitt
>Sent: Monday, May 08, 2006 8:58 PM
>To: kitfox-list@matronics.com
>Subject: Re: Kitfox-List: Thrust - Over Rated?
>
>--> Kitfox-List message posted by: "Lowell Fitt" <lcfitt@sbcglobal.net>
>
>Randy,
>
>No flames here. I have two friends that went to the PowerFin. They had
>the
>
>exact issues you had and eventually went to the shortened blades. They got
>the improvements you did. One is now with the Warp and doesn't know if he
>likes it. I think the other still has the Powerfin. They'll both be at
>the
>
>Cameron Park fly-in.
>
>I guess that is what the poor man's dyno was all about - finding the HP at
>the prop.
>
>Lowell
>----- Original Message -----
>From: "Randy Daughenbaugh" <rjdaugh@rapidnet.com>
>To: <kitfox-list@matronics.com>
>Sent: Monday, May 08, 2006 7:08 PM
>Subject: Kitfox-List: Thrust - Over Rated?
>
>
> > --> Kitfox-List message posted by: "Randy Daughenbaugh"
> > <rjdaugh@rapidnet.com>
> >
> > I have been seeing discussion of thrust lately and I think it is nearly
> > irrelevant.
> >
> > I have a PowerFin three blade prop on a 912S Series 5/7. When I first
>set
> > it up, static RPM was 5800 RPM. And MAN DID IT HAVE THRUST! The
> > acceleration would make your head snap back as you pushed the throttle
>in.
> > Well, it came time for first flight, and boy did it get off the ground
> > fast!
> > I don't have good numbers, but I am guessing about 150 feet ground roll.
> > BUT (you had to know that was coming), it would only fly about 65 - 70
>mph
> > without over-reving the engine.
> >
> > So I put in more pitch on the prop. Got up to 85 mph. But lower static
> > rpm, less thrust and acceleration, longer ground roll. Added more pitch
>-
> > 95 mph, and less thrust. More pitch - WOT about 108 mph - cruise at
>5500
> > rpm about 96 mph - static rpm about 4900 rpm. But now ground roll on
>take
> > off approaching 500 ft. Spam can territory!
> >
> > PowerFin said they would shorten the prop 1" each blade. I finally took
> > them up on it, but it was a tough decision for me.... When I put it
>back
> > on
> > the plane, I added a degree and a quarter more pitch. Now I cruise at
>106
> > mph AND off the ground much quicker - maybe 275' solo.
> >
> > In short, if you want more thrust, all you have to do is sacrifice top
> > speed. Therefore, thrust is irrelevant.
> >
> > Indeed, it is more complicated than that. An "efficient" prop slips
> > enough
> > on take off to get the rpm up so that you can use most of your horse
>power
> > to get off the ground, but still has enough pitch so that you can get a
> > decent top speed. My plane is "over prop'ed" with the three blade
> > PowerFin.
> > I am saving my nickels for the Sensinich ground adjustable two blade.
> >
> > I would have written this earlier but was in Montana visiting my new
> > grandson and didn't have my flame suit with me.
> >
> > Randy - Everything in aviation is a compromise.
> >
> > .
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
>
>
_________________________________________________________________
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Message 17
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| Subject: | Re: Thrust - Over Rated |
--> Kitfox-List message posted by: "John Anderson" <janderson412@hotmail.com>
Youre right Rick, fixed pitch are a compromise and some better than others.
But I have to say, I seem to have stumbled on a beauty...3 blade 72" tapered
tip Warpdrive. Good acceleration and 97kt cruise, I do have strut fairings,
gap seals, exit fairing on the radiator and spats so I guess this all helps.
But impressed as to how well that wee prop does. John A.
From: "wingsdown" <wingsdown@comcast.net>
Subject: RE: Kitfox-List: Re: Thrust - Over Rated
--> Kitfox-List message posted by: "wingsdown" <wingsdown@comcast.net>
If you have to turn the engine as fast or nearly so for take off as for
fast flight, then an in-flight adjustable prop has merit. Even slow
turning dinosaur engines for the most part have constant speed props.
Band-Aids come in all shapes and sizes. Some are built right in and you
never see them or for that matter know they are there. And are quite
subjective as to definition.
Rick
-----Original Message-----
From: owner-kitfox-list-server@matronics.com
[mailto:owner-kitfox-list-server@matronics.com] On Behalf Of Lowell Fitt
Sent: Tuesday, May 09, 2006 7:05 AM
Subject: Re: Kitfox-List: Re: Thrust - Over Rated
--> Kitfox-List message posted by: "Lowell Fitt" <lcfitt@sbcglobal.net>
Mike, I couldn't agree with you more. However there are airframe -
engine - prop combinations that will give enough of each with a fixed
pitch
prop that the cost / benefit and complexity just hasn't made me even
think
about yet.
In our airplanes, I think an argument could be made that a cockpit
adjustable prop is sort of like a bandade for a mismatched engine -
airframe.
Personally I like the simplicity in flight and the lack of prop
maintenane
issues of the old fashioned ground adjustable Warp Drive prop. I can
almost
keep up with the PowerFin in climb and cruise has never been an issue
for
me, I can get plenty.
Lowell
----- Original Message -----
From: "Michael Gibbs" <MichaelGibbs@cox.net>
Sent: Tuesday, May 09, 2006 12:48 AM
Subject: Kitfox-List: Re: Thrust - Over Rated
> --> Kitfox-List message posted by: Michael Gibbs
> --> <MichaelGibbs@cox.net>
>
> Randy sez:
>
>>In short, if you want more thrust, all you have to do is sacrifice top
>>speed. Therefore, thrust is irrelevant.
>
> If you want more thrust AND more top speed, you get an in-flight
> adjustable prop. You wouldn't drive your car in one gear all the
> time, why operate your airplane that way?
>
> Mike G.
> N728KF
>
>
>
>
>
>
>
>
>
>
>
>
_________________________________________________________________
Read the latest Hollywood gossip @ http://xtramsn.co.nz/entertainment
Message 18
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| Subject: | Re: Tundra tyres. |
--> Kitfox-List message posted by: kurt schrader <smokey_bear_40220@yahoo.com>
Michel,
I think the folded innertube problem is much like my
tread seperation problem. Good suggestion. It could
be that simple. 11 psi isn't much and the cold
operations might be enough to spin the tires a little
and roll up the innertube? Or pinched just from
assembly?
One thing to try is to blow them up to the max
pressure for a bit, especially if it is warm that day.
Taxi around and see if things stretch out.
If not, do as was suggested and take a wheel apart and
see if the innertube is creased. Put it back together
with the powder so it can slip in place.
Just an idea.
Now I've got to go clean the wheat out of my 767
tires... ;-)
Kurt S.
--- Michel Verheughe <michel@online.no> wrote:
> From: kurt schrader [smokey_bear_40220@yahoo.com]
> > Have you seen any crop circles lately? ;-)
>
> Yes, concentric circles about the size of the
> distance between the main gears of a B-767 and your
> name was all over it! The Norwegian authorities are
> being informed! :-)
>
> > I had a tire on my van where the tread looked
> fine, but seperated internally and
> > got a big flat spot.
>
> That could have happened to me too. I'll need to
> look at it. But, Ron and Kurt, here a good analogy:
> If you press hard with your thumb on the fabric of
> your wing, you'll make a hollow that will come back
> to normal after a time and/or with the help of heat.
>
> Well, my tyres are exactly the same, except that
> they don't seem to come back to the normal smooth
> and round shape. Since there is nothing visible on
> the outside, maybe there is something damaged on the
> inside. But I can't imagine what, when I look at the
> inside of the old tyres. What do you think?
>
> Cheers,
> Michel
__________________________________________________
Message 19
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| Subject: | Re: Thrust - Over Rated |
--> Kitfox-List message posted by: kurt schrader <smokey_bear_40220@yahoo.com>
My flame suite on for another long one.....
---------------------------------
> Randy sez:
>
> >In short, if you want more thrust, all you have to
> >do is sacrifice top speed. Therefore, thrust is
> >irrelevant.
> -------------------------
> Mike G.
> N728KF
> If you want more thrust AND more top speed, you get
> an in-flight adjustable prop. You wouldn't drive
> your car in one gear all the time, why operate your
> airplane that way?
----------------------------
Good point Mike,
There is a misunderstanding on the list of thrust, HP
and torque. The whole purpose of the prop is to
convert power into thrust. Thrust is the most
relevant measure. It moves the plane.
But we are not talking about static thrust. You need
the best thrust at the speed you are flying for best
performance. Max static thrust is best at zero speed
only. Max takeoff thrust is best somewhere around 1/2
your takeoff speed. Max climb thrust is best at climb
speed. Max cruise thrust is best at.... ahhh you get
it.
A fixed pitch prop will give you its max thrust at
only one speed. You are compromising only in that you
pick the speed you want to have it perform best at.
At all other speeds, faster or slower, it will give
less then max thrust.
A variable or constant speed prop will still have one
best speed, but the curve will be flatter. It will
perform almost as well at all speeds as a fixed pitch
prop for its one speed.
Say a cruise fixed pitch gives efficiencies of:
50% in takeoff
75% in climb
85% in cruise
A climb prop might give:
65% in takeoff
85% in climb
80% in cruise
The variable prop might give:
75% in takeoff
82% in climb
83% in cruise
I have a friend who has a Champ product, his 3rd in 2
years. His 150 HP constant speed Champ would perform
equal to his 180 HP fixed pitch Champ, except around
one speed. That speed depended upon which fixed pitch
prop he installed. He might get better climb, but
equal cruise, or better cruise, but equal climb from
the extra 30 HP.
In his case, he used the prop that meant they cruised
equally, but the fixed pitch climbed better with the
30 more HP. If it had a constant speed prop, it would
have used the 30 extra HP for better performance all
across the speed range. His fixed pitch got off the
ground better, but burned more for the same cruise
speed.
Another way to say it is that the variable prop was
almost worth the 30 extra HP.
This is my problem with static thrust measurements.
It only gives you the measurement for the best prop at
no speed. How useful is that? I think that is what
Randy was saying.
Static thrust is only good when static. It is already
losing performance in the takeoff roll, but not so
badly as when at cruise speed. A cruise prop would be
poor but increasing performance in the takeoff roll,
and continue to get better all the way up to cruise.
The climb prop is of course in between, getting
better, then getting worse as speed increases.
As to HP and torque, if you are swinging a 2x4 around
with your engine, it will take HP and torque to do,
but produce no thrust. If you have a feathered prop,
it will take lots of HP and torque to swing and still
produce no thrust. The efficiency of the prop to
produce thrust is what makes the hp and torque
meaningful.
As a prop increases pitch, it moves more toward a
feathered prop in that the angle of lift of the prop
is more against torque and less forward producing
thrust. Lift of the prop is always about 90 degrees
to the blade. A pitch of say 20 degrees means that
some of the prop's lift is pulling air in a circle and
not just pushing it back. That takes HP.
When I flew the C-130, the pitch could be as high as
55 degrees in cruise. More than 1/2 the HP went to
spinning the air and less than 1/2 went to thrust.
Our props don't get that bad due to our less pitch.
But a heavily pitched prop may take the same HP/torque
as a finer pitched prop at higher RPM. The faster
turning, lower pitched prop will produce more thrust,
to a point. That point is determined by the most
efficient rpm for the prop compared to mach number,
and the most efficient rpm for the engine. Those 2
may not match.
A less efficient prop may take more HP or torque to
give the same performance, not more. A more efficient
prop will give more thrust with the same HP/torque.
HP and torque don't tell the whole story. They don't
give thrust, except as the prop allows.
So I am saying this. The prop that produces the most
thrust will be the one that has its best speed closest
to your engine's favorite RPM, but does it at the
speed you are flying. Also it has to be the most
aerodynamically efficient.
Max static thrust equals first gear only. Takeoff
props equal second gear. Climb props equal third
gear. Cruise props are overdrive. Variable props are
automatic trannys. That is Mike's point.
The actual performance of the plane will be determined
by just how much thrust it can produce today on this
fuel, at this temp, at this density altitude, with
this prop, at this speed, with these sparkplugs, at
this rpm and manifold setting..... You can measure
all that, or you can just measure thrust.
So thrust is really the key, but it has to be measured
now, at your speed and with all variables.
Static thrust is good for fans, not planes.
Thrust is what happens after all the variables are in
place. HP and torque are only what you are putting
into a prop, not what is coming out, which changes
with prop efficiency, speed, air density.....
So that is why I wanted a meter that simply measures
the thrust output on board at all speeds, altitudes,
settings, etc. It will tell you what performance you
are getting now, whatever now is.
And instead of HP, you can simply measure fuel flow if
the engine is tuned right. That is, if the fuel air
ratio is the same, fuel in equals power out.
That you can compare to whatever you want to change
and see if it made things better or worse. 10% more
thrust with the same fuel flow is 10% better no matter
how you got it. 10% more HP or 10% more torque might
just mean a 10% worse prop is giving equal thrust for
more gas.
Bottom line: Thrust = performance. Fuel flow =
energy and $ in to produce the thrust. The best prop
will be the one that gives you the most thrust per
fuel flow at the speed you want it.
A fixed pitch will peak at a given speed with a strong
curve. A variable prop will have a broader curve.
You have to pick the prop that peaks at the speed and
rpm that best matches your engine and most important
performance goal. This is critical for fixed pitch,
but less critical for variable.
Then you can compare one prop against another to see
which gives the most thrust at the same fuel flow.
Is this too much at once? Hope it can be understood.
You want thrust. Thrust moves the plane. We just
aren't use to measuring it directly. Fuel flow is
what we pay to get it and max fuel flow is how much
power is available under present conditions.
One day I will simplify this.....
Kurt S. S-5 flying and 1/2 done.
__________________________________________________
Message 20
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| Subject: | Re: Thrust - Over Rated |
--> Kitfox-List message posted by: kurt schrader <smokey_bear_40220@yahoo.com>
Well John,
Rick does understand props and engines. But you've
done great too, having picked and built all that stuff
yourself.
What engine and prop RPM are you using? What fuel
flow for takeoff and cruise? Inquiring minds want to
know. ;-) Especially since some of us have the same
blades, just cockpit adjustable and maybe different
rpms. Hard to actually compare on different planes, I
know, but it helps a little.
Kurt S.
--- John Anderson <janderson412@hotmail.com> wrote:
> You're right Rick, fixed pitch are a compromise and
> some better than others.
> But I have to say, I seem to have stumbled on a
> beauty...3 blade 72" tapered
> tip Warpdrive. Good acceleration and 97kt cruise, I
> do have strut fairings,
> gap seals, exit fairing on the radiator and spats so
> I guess this all helps.
> But impressed as to how well that wee prop does.
> John A.
>
> From: "wingsdown" <wingsdown@comcast.net>
> To: <kitfox-list@matronics.com>
> Subject: RE: Kitfox-List: Re: Thrust - Over Rated
> Date: Tue, 9 May 2006 07:27:04 -0700
>
> --> Kitfox-List message posted by: "wingsdown"
> <wingsdown@comcast.net>
>
> If you have to turn the engine as fast or nearly so
> for take off as for
> fast flight, then an in-flight adjustable prop has
> merit. Even slow
> turning dinosaur engines for the most part have
> constant speed props.
> Band-Aids come in all shapes and sizes. Some are
> built right in and you
> never see them or for that matter know they are
> there. And are quite
> subjective as to definition.
>
> Rick
__________________________________________________
Message 21
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| Subject: | 912S/ oil cooler efficiency |
--> Kitfox-List message posted by: Fred Shiple <fredshiple@sbcglobal.net>
I've a question regarding oil cooler efficiency on a Kitfox with a 912S:
My Series 6/ 912S was built with the Skystar optional oil cooler. During the past
two summers at temps over 95F I'd have to lower the nose after talk off/climb
after about 1 to 1 1/2 minutes as oil temp reached 260F (red line 266F). At
100F (a rare occurance in NW Ohio) had to throttle back from 75% to 65% for the
same reason.
Now that I'm flying on floats, I've begun to see the same thing at 75-80 degrees.
I'm flying 12-15 mph slower (at the same rpm/manifold pressures) as anticipated
with the extra drag. The water and cylinder head temps have remained well
in the green with or without the floats. I saw temps consistant with prior
years operations in the month prior to install of the floats two weeks ago.
Any advice is appreciated as I'm now concerned about warmer weather operation.
Fred
Message 22
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| Subject: | Thrust...Overrated? |
--> Kitfox-List message posted by: "Clem Nichols" <cnichols@scrtc.com>
This is a little apart from the question of thrust, but of parallel =
interest in the sense that it has to do with airplane performance. I =
gather that most Kitfoxers use 3-bladed props just as I do, but it's my =
understanding (perhaps incorrectly) that the more blades a prop has the =
less efficient it is. I know that Randy Schlitter who manufactures the =
Rans S6S, a plane much like the Kitfox, provides a 2-blade wooden prop =
with his kits, and states in his literature that (in his opinion, at =
least) he's never seen a 3-blade prop that works better than a 2-blade =
one. (I hope I haven't misquoted him on this. I couldn't find the =
brochure to check against my memory). I realize the 3-blade by virtue =
of being shorter in diameter is less likely to strike the ground in a =
botched tail-dragger landing. I was just wondering if anyone in the =
group is using a 2-blader, and if so, what their opinion is of it.
Kurt, your message on thrust was most enlightening.
Clem Nichols
Message 23
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| Subject: | Re: 912S/ oil cooler efficiency |
--> Kitfox-List message posted by: John King <kingjohne@adelphia.net>
Fred,
I have a Series 6 powered by a 912S and haven't had excessively high oil
temperatures in hot weather. Have you calibrated your oil temperature
sensor against a standard or accurate gauge? Send me a picture of your
oil cooler inlet on the cowling. and the dimensions of the oil cooler.
I'll make a comparison with mine and send you a picture of my configuration.
--
John King
Warrenton, VA
Fred Shiple wrote:
>--> Kitfox-List message posted by: Fred Shiple <fredshiple@sbcglobal.net>
>
>I've a question regarding oil cooler efficiency on a Kitfox with a 912S:
>My Series 6/ 912S was built with the Skystar optional oil cooler. During the past
two summers at temps over 95F I'd have to lower the nose after talk off/climb
after about 1 to 1 1/2 minutes as oil temp reached 260F (red line 266F). At
100F (a rare occurance in NW Ohio) had to throttle back from 75% to 65% for
the same reason.
>Now that I'm flying on floats, I've begun to see the same thing at 75-80 degrees.
I'm flying 12-15 mph slower (at the same rpm/manifold pressures) as anticipated
with the extra drag. The water and cylinder head temps have remained well
in the green with or without the floats. I saw temps consistant with prior
years operations in the month prior to install of the floats two weeks ago.
>Any advice is appreciated as I'm now concerned about warmer weather operation.
>Fred
>
>
>
>
Message 24
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| Subject: | Re: Thrust - Over Rated |
--> Kitfox-List message posted by: "John Anderson" <janderson412@hotmail.com>
Early days on fuel flow but seems to be around 15 litres per hour and I
don't have a flow meter. 4500 on t/o, more there if I want with prop setting
but that's what I use, climb 1200fpm. 97kts at 4300. Just me in it tho at
this early stage. John
From: kurt schrader <smokey_bear_40220@yahoo.com>
Subject: RE: Kitfox-List: Re: Thrust - Over Rated
--> Kitfox-List message posted by: kurt schrader
<smokey_bear_40220@yahoo.com>
Well John,
Rick does understand props and engines. But you've
done great too, having picked and built all that stuff
yourself.
What engine and prop RPM are you using? What fuel
flow for takeoff and cruise? Inquiring minds want to
know. ;-) Especially since some of us have the same
blades, just cockpit adjustable and maybe different
rpms. Hard to actually compare on different planes, I
know, but it helps a little.
Kurt S.
--- John Anderson <janderson412@hotmail.com> wrote:
>You're right Rick, fixed pitch are a compromise and
>some better than others.
>But I have to say, I seem to have stumbled on a
>beauty...3 blade 72" tapered
>tip Warpdrive. Good acceleration and 97kt cruise, I
>do have strut fairings,
>gap seals, exit fairing on the radiator and spats so
>I guess this all helps.
>But impressed as to how well that wee prop does.
>John A.
>
>From: "wingsdown" <wingsdown@comcast.net>
>To: <kitfox-list@matronics.com>
>Subject: RE: Kitfox-List: Re: Thrust - Over Rated
>Date: Tue, 9 May 2006 07:27:04 -0700
>
>--> Kitfox-List message posted by: "wingsdown"
><wingsdown@comcast.net>
>
>If you have to turn the engine as fast or nearly so
>for take off as for
>fast flight, then an in-flight adjustable prop has
>merit. Even slow
>turning dinosaur engines for the most part have
>constant speed props.
>Band-Aids come in all shapes and sizes. Some are
>built right in and you
>never see them or for that matter know they are
>there. And are quite
>subjective as to definition.
>
>Rick
__________________________________________________
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Find the coolest online games @ http://xtramsn.co.nz/gaming
Message 25
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| Subject: | Re: 912S/ oil cooler efficiency |
--> Kitfox-List message posted by: Fred Shiple <fredshiple@sbcglobal.net>
John,
I calibrated it two years ago when it was installed (boiling water). Will get picks
and measurements to you tomorrow.
Fred
temperatures in hot weather. Have you calibrated your oil temperaturesensor against
a standard or accurate gauge? Send me a picture of your
Message 26
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| Subject: | Re: Elevator hinge tab question?? |
--> Kitfox-List message posted by: "darinh" <gerns25@netscape.net>
Thanks to all who responded. I have solved the problem using a nifty little gadget
I picked up at the local Lowe's. It is a flexibly drill shaft. I simply
installed a 13/64 bit and drilled out the elevator tabs to allow for 1/32" oversized
hole. The elevator went together excellent and works great! Thanks again,
Darin
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