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dospi(at)epm.net.co
Guest

Posted: Tue Feb 07, 2006 7:27 am Post subject: VG Installation

Sorry for bringing this subject once again to the list. I've just received a

set of VG's from Landshorter and I'd like to skip the temporary installation

so, has anybody found the best placement for a Mark III?



 



DO NOT ARCHIVE



 



Diego Ospina



Kolb Mark III



Colombia

Richard Pike

Joined: 09 Jan 2006
Posts: 1671
Location: Blountville, Tennessee

Posted: Tue Feb 07, 2006 8:35 am Post subject: VG Installation

No. Nobody has found the best placement for VG's on a MKIII wing, and 

nobody ever will. VG's on Kolb's are like Seafoam, 2 strokes vs. 4 

strokes, and when Vamoose will finally fly. Such topics are endlessly 

discussed and argued over, but nothing is ever resolved. Such is the 

nature of the Kolb list.



However, if you use a flexible tape measure and go from the center of 

the leading edge tube up a false rib for ten and a half, or ten and 

three quarter inches, or eleven inches, or eleven and one quarter 

inches, and install them at that distance, your stall speed will go 

down, your slow flight handling will go up, you will be happy, and then 

you too will be able to argue the merits of your particular VG 

placement, and the Kolb list will continue to thrive.



You will have done your part.



Richard Pike

MKIII N420P (420ldPoops)

Diego Ospina wrote:

 	  Quote: 	
		   



 Sorry for bringing this subject once again to the list. I've just received a

 set of VG's from Landshorter and I'd like to skip the temporary installation

 so, has anybody found the best placement for a Mark III?



  



 DO NOT ARCHIVE



  



 Diego Ospina



 Kolb Mark III



 Colombia

_________________
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kingsport, TN 3TN0

Forgiving is tough, being forgiven is wonderful, and God's grace really is amazing.

JetPilot

Joined: 10 Jan 2006
Posts: 1246

Posted: Tue Feb 07, 2006 2:20 pm Post subject: Re: VG Installation

 	  Richard Pike wrote: 	
		  No. Nobody has found the best placement for VG's on a MKIII wing, and 

nobody ever will. VG's on Kolb's are like Seafoam, 2 strokes vs. 4 

strokes, and when Vamoose will finally fly. Such topics are endlessly 

discussed and argued over, but nothing is ever resolved. 	




Hola Diego !!!  Hace tiempo que no eschucho nada de ti....



I can not disagree with Richard more on this.  There is most definately a best place to put VG's.  The placement and angle of the VG's is critical to get the maximum benefit from them while not inducing to much darg.  The big question is, has anyone done the testing needed to find out the optimum placement of VG's for the MK-III,  and that I dont know.



I plan on using the same VG's on my MK-III , so be sure you post your results.  Baring someone having done testing with them on the MK-III, I would put them on as per the instructions provided with them.  Wherever you end up putting them, make sure you get the placement and angles very close, otherwise you might end up with VG's that do not work as well as they should.



Michael A. Bigelow

_________________
"NO FEAR" - If you have no fear you did not go as fast as you could have !!!

Kolb MK-III Xtra, 912-S

Richard Pike

Joined: 09 Jan 2006
Posts: 1671
Location: Blountville, Tennessee

Posted: Tue Feb 07, 2006 4:17 pm Post subject: VG Installation

I forgot that tongue-in-cheek humor is not always recognized. My 

apologies. Perhaps I should have said something more like the following -

I spent a lot of time and effort moving VG's around on my MKIII, and 

eventually settled on what I felt was optimum. I spent a lot more time 

moving the VG's around on the Firestar II to come up with what seemed 

optimum. And have expressed said opinions on numerous occasions. 

Probably way too numerous.

Notwithstanding, since this is a list, and since builders of 

experimental airplanes tend to experiment, we have on this list a large 

number of other worthies who have placed their VG's (of different sizes 

and shapes) at different places, different angles, and anything else you 

can think of, and all of them will vigorously defend that theirs is the 

best placement. Which is why my original post (the part that got snipped 

out) offered four different places to put the VG's - because in my 

experience, on both the MKIII and the FSII, those placements actually 

worked pretty good. And if I had quit experimenting at that point, I 

would probably have thought them to be optimum.

Having said that, I have a Kolb-owning friend who is also on this list, 

he lives about ten miles from here, and on his almost identical FSII, 

the optimum placement for VG's is a bit different from ours, what was 

optimum for him was not optimum for us, and vice versa.

Consequently (pay close attention here) when you get around to actually 

putting VG's on your MKIII, whatever your optimum placement is will 

probably be different from mine, and probably from everybody else's on 

this list because they are Experimental airplanes, no two are exactly 

alike, they all are slightly different. Different equations give 

different results.

To further answer your question, many people have done extensive 

testing, and have found optimum placements - on their airplanes. Which 

are not exactly the same as on my airplane. And will probably not be the 

same as on your airplane.  So you too will have to do extensive testing 

to find optimum placement - on your airplane.

As far as ending up with VG's that do not work as well as they should - 

the Kolb already flies great. You add VG's any where within the accepted 

parameters, it flies even better.

Moral of the story: it is great to ice the cake, it makes the cake 

better, but if the icing is not perfect, so what? It's still better.

Just be careful you don't end up inducing too much darg.  Actually, I no 

longer have a darg, I used to have one but she died of old age. However, 

I still remember that she really hated being induced....

Richard Pike

MKIII N420P (420ldPoops)

JetPilot wrote:

 	  Quote: 	

 Richard Pike wrote:

> No. Nobody has found the best placement for VG's on a MKIII wing, and 

> nobody ever will. VG's on Kolb's are like Seafoam, 2 strokes vs. 4 

> strokes, and when Vamoose will finally fly. Such topics are endlessly 

> discussed and argued over, but nothing is ever resolved. 

>     

 Hola Diego !!!  Hace tiempo que no eschucho nada de ti....

 I can not disagree with Richard more on this.  There is most definately a best place to put VG's.  The placement and angle of the VG's is critical to get the maximum benefit from them while not inducing to much darg.  The big question is, has anyone done the testing needed to find out the optimum placement of VG's for the MK-III,  and that I dont know.

 I plan on using the same VG's on my MK-III , so be sure you post your results.  Baring someone having done testing with them on the MK-III, I would put them on as per the instructions provided with them.  Wherever you end up putting them, make sure you get the placement and angles very close, otherwise you might end up with VG's that do not work as well as they should.

 Michael A. Bigelow

 --------

 NO FEAR -  If you have no fear you did not go as fast as you could have !!!

 Read this topic online here:

 http://forums.matronics.com/viewtopic.php?p=10692#10692

_________________
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kingsport, TN 3TN0

Forgiving is tough, being forgiven is wonderful, and God's grace really is amazing.

jbhart(at)onlyinternet.ne
Guest

Posted: Tue Feb 07, 2006 4:44 pm Post subject: VG Installation

At 02:20 PM 2/7/06 -0800, you wrote:

 	  Quote: 	
		  

I can not disagree with Richard more on this.  There is most definately a best place to put VG's.  The placement and angle of the VG's is critical to get the maximum benefit from them while not inducing to much darg.  The big question is, has anyone done the testing needed to find out the optimum placement of VG's for the MK-III,  and that I dont know.




	


The archives are full of info on where people have located vg's.  Do a 

survey, take an average and use this as your initial guess.  For the 

nonbeliever, the only solution is get busy and mount vg's and move them 

around until they have what they consider to be the best solution for them.  



Have at it and let us know what you find.



Jack B. Hart FF004

Winchester, IN

biglar

Joined: 14 Jan 2006
Posts: 457

Posted: Tue Feb 07, 2006 5:19 pm Post subject: VG Installation

Howcum my ears are burning ??                Do not Archive.



Larry Bourne

Palm Springs, CA

Building Kolb Mk III

N78LB  Vamoose

www.gogittum.com



---

_________________
Larry Bourne
Palm Springs, CA
Building Kolb Mk IIIC
"Vamoose"

George Alexander

Joined: 10 Jan 2006
Posts: 245
Location: SW Florida

Posted: Tue Feb 07, 2006 5:52 pm Post subject: Re: VG Installation

 	  Richard Pike wrote: 	
		  I forgot that tongue-in-cheek humor is not always recognized. My 

apologies. Perhaps I should have said something more like the following -

	


<<<<<SNIP A BUNCH OF GOOD STUFF>>>>>

 	  And then Richard Pike some more good stuff wrote: 	
		  

To further answer your question, many people have done extensive 

testing, and have found optimum placements - on their airplanes. Which 

are not exactly the same as on my airplane. And will probably not be the 

same as on your airplane.  So you too will have to do extensive testing 

to find optimum placement - on your airplane.

	


Well said Brother Pike!  And for those who would doubt any of the above, as well as the aforementioned "GOOD STUFF", I would refer them to the photographic evidence as presented by the infamous Beauford, the Aluminum Butcher from Brandon, as currently archived in the Photoshare Vault.



For those of you who don't want to bother to search the archives:



http://www.matronics.com/photoshare/beauford(at)tampabay.rr.com.11.27.2004/

DO NOT ARCHIVE

_________________
George Alexander
FS II R503
E-LSA N709FS
http://www.oh2fly.net

neilsenrmf(at)comcast.net
Guest

Posted: Tue Feb 07, 2006 9:17 pm Post subject: VG Installation

George George George



You just had to go and do that again. You didn't mention that Buford did 

that to improve his inverted performance. With those VGs his inverted loops 

look more like snap rolls.



For those that don't know Bill he sometimes pulls our leg or for those 

across the pond "humor"



Do not archive



Rick Neilsen

Redrive VW powered MKIIIc



---

edchmiel(at)mindspring.co
Guest

Posted: Tue Feb 07, 2006 9:35 pm Post subject: VG Installation

Hi Mike,



         While he may be too modest to point it out, the good Rev. Pike is 

one of the most experienced Kolbers out there, and his experiences with VG's 

on various Kolbs bear out many of my own.  In my case, I fly a varied group 

of GA singles and twins with at least 3 different makes of VG's on them. 

They vary in size and placement, number and angle, but they seem to be one 

of those 'close is enough' devices.  A quarter-inch doesn't make any 

difference, as does one or two falling off.  When you get some real-world 

experience, let us know how they work out.



Ed in JXN

MkII/503



---

WhiskeyVictor36(at)aol.co
Guest

Posted: Tue Feb 07, 2006 10:15 pm Post subject: VG Installation

In a message dated 2/7/2006 7:18:37 P.M. Eastern Standard Time,  

richard(at)bcchapel.org writes:



I forgot  that tongue-in-cheek humor is not always recognized. My 

apologies. Perhaps  I should have said something more like the following  -



You guys are causing me to laugh.  If nothing else, its good  medicine for 

cabin fever.

 

 

Bill  Varnes

Original Kolb FireStar

Audubon NJ

Do Not  Archive

kiwimick

Joined: 10 Jan 2006
Posts: 25
Location: ENGLAND

Posted: Wed Feb 08, 2006 12:59 am Post subject: VG Installation

All I agree with jetpilot, there is a definate correct position, We have got 

UK approval for these on the XTRA and have them fitted to a 582 powered one 

and several JAb powered ones and the are fitted in the same place, the posn 

is determined by the wing section itself.

I have posted all this in the past.

If we have got UK approval for them rest assured they are in the correct 

place for the Mk III wing, nothing ever gets through this system without 

full testing, (infact 25hrs flight testing, along with anaylsis and two 

confirmation flights, one with the CAA chief test pilotand one with the PFA 

chief engineer).

Kind REgards

Mike Moulai

G-CDFA

Xtra/Jab

121 hrs now

---

_________________
Mike the kiwi Kolber in England.......

jbhart(at)onlyinternet.ne
Guest

Posted: Wed Feb 08, 2006 6:43 am Post subject: VG Installation

At 08:56 AM 2/8/06 -0000, you wrote:

 	  Quote: 	
		  


	


 	  Quote: 	
		  I have posted all this in the past.




	


 	  Quote: 	
		  From the archives:


	


Match: 	#2

Message: 	#41228

From: 	"mike moulai" <kiwimick(at)sfmicro.fsnet.co.uk>

Subject: 	Re: VORTEX GENERATORS

Date: 	Jan 18, 2006



    All, The Landshorter VG's we have extensively tested and gained approval 

for on our Xtra in the UK are spaced at 3" and at 10% of wing chord, this is 

225 millimeters back measured from the front apex of the L/E up over the 

camber. Hope this helps. 



Mike 

Xtra/Jab2200



Jack B. Hart FF004

Winchester, IN



do not archive

Richard Pike

Joined: 09 Jan 2006
Posts: 1671
Location: Blountville, Tennessee

Posted: Wed Feb 08, 2006 6:43 am Post subject: VG Installation

So even though we extensively tested our Kolbs, and the FSII's flight 

performance during the 40 hour test period was excellent, we would still 

have to wait for a Fed to come and fly it? And then wait for another Fed 

to come and fly it? Last week, the FSII clicked over it's first 100 

hours, took right at a year. Perhaps your system works quicker, but if 

we had had to wait for the Feds to come and fly it, we'd be lucky to 

have flown it at all. When I added VG's to my MKIII, I had to advise the 

FAA of a major mod in the flying characteristics and then refly a test 

period, which is required by the regs.



I think what we have here is a difference in perceptions. In the US, our 

perception is to keep the FAA/Feds at arms length. In your situation, it 

appears necessary to embrace them. I'm sure your system is better 

documented, but I think I prefer our system.



Richard Pike

MKIII N420P (420ldPoops)



mike moulai wrote:

[quote] 



 All I agree with jetpilot, there is a definate correct position, We have got 

 UK approval for these on the XTRA and have them fitted to a 582 powered one 

 and several JAb powered ones and the are fitted in the same place, the posn 

 is determined by the wing section itself.

 I have posted all this in the past.

 If we have got UK approval for them rest assured they are in the correct 

 place for the Mk III wing, nothing ever gets through this system without 

 full testing, (infact 25hrs flight testing, along with anaylsis and two 

 confirmation flights, one with the CAA chief test pilotand one with the PFA 

 chief engineer).

 Kind REgards

 Mike Moulai

 G-CDFA

 Xtra/Jab

 121 hrs now

 ---

_________________
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kingsport, TN 3TN0

Forgiving is tough, being forgiven is wonderful, and God's grace really is amazing.

n79rt(at)kilocharlie.us
Guest

Posted: Wed Feb 08, 2006 6:47 am Post subject: VG Installation

All I agree with jetpilot, there is a definate correct position, We have

got 

UK approval for these on the XTRA and have them fitted to a 582 powered

one 

and several JAb powered ones and the are fitted in the same place, the

posn 

is determined by the wing section itself.

I have posted all this in the past.

If we have got UK approval for them rest assured they are in the correct



place for the Mk III wing, nothing ever gets through this system without



full testing, (infact 25hrs flight testing, along with anaylsis and two 

confirmation flights, one with the CAA chief test pilotand one with the

PFA 

chief engineer).

Kind REgards

Mike Moulai

G-CDFA

Xtra/Jab

121 hrs now



<snip>



OK...let me rephrase this discussion just a little...this is kind of

like a story I heard once about the young aeronautical engineer that got

his first really big assignment after getting his first "real"

job...they were designing what became the F-102 Delta Dart as I recall

and the young AE was told "optimize" the wing...this young fellow worked

for weeks and weeks and tried multiple airfoil sections and just worked

the wind tunnel guys to death.  His boss finally got wind of his

exploits and started checking up on him.  When he asked the young AE

what all the fuss was about he explained all the testing he had been

doing and the results he had gotten so far and smiled proudly.  The boss

had a piece of plywood cut to the same dimensions as the test wing they

had been flying in the wind tunnel and after flying it too, they found

that it performed within a couple of percentage points in all

respects...



Lets all remember...VG's are only there to energize the boundary layer

thus preventing separation.  As long as the VG's are in front of the

point of separation then they will do their job.  You can tweak them a

little forward or whatever but they do the same thing.  The exact angle

of cant to them and the exact spacing isn't "critical" (and I put that

in quotes to mean within reason...if you get one at 13 degrees instead

of 15 it certainly isn't worth peeling off glue and trying to reset

it...)



The STC'd VG sets that have limits on how many can be broke off before

you must ground the plane (3 on a wing per the Cessna 152 STC...) is

just horse hockey legal liability lawyer talk...bottom line is they

demonstrated to the FAA that that many missing didn't adversely affect

anything (at least measurably...refer to previous story for a definition

of "measurably"  a fourth one missing won't make the plane due snap

rolls at stall...



Remember these planes built by mere mortals are NEVER going to be

identical...having a little more/less tension on the fabric when gluing

the edges or a iron calibrated a little differently can vary the amount

of fabric sag between the ribs which WILL change the airfoil

section...which would change the "OPTIMUM" position of the VG's...right?



Enough...I'm boring myself now...



Jeremy Casey

John Hauck

Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)

Posted: Wed Feb 08, 2006 7:07 am Post subject: VG Installation

|    All, The Landshorter VG's we have extensively tested and gained 

approval

| for on our Xtra in the UK are spaced at 3" and at 10% of wing chord, 

this is

| 225 millimeters back measured from the front apex of the L/E up over 

the

| camber. Hope this helps.

|

| Mike

| Xtra/Jab2200

Kiwi Mick:



Was curious how the individual VG placement works out with the rib and 

false rib spacing of the wing?



Fabric is naturally pulled down somewhat between the ribs when heat 

shrunk.  How does VG placement work with these valleys if we use 3" 

seperation?



Homer Kolb says these valleys play an important role in the 

performance of his wing.  Do the VGs interfere with these valleys and 

their performance, or does the 225mm place the VGs aft of the valleys.



I'm simply curious.  Have no immediate intentions to place VGs on my 

wings.  Surprisingly enough, I continue to be  pleased the way my 

airplane has been flying all these years.  Haven't found a need to 

change/improve their performance, yet.



Take care,



john h

MKIII-2,445.9 hours

912S-1,100.0 hours

_________________
John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama

pj.ladd(at)btinternet.com
Guest

Posted: Wed Feb 08, 2006 7:52 am Post subject: VG Installation

In the US, our perception is to keep the FAA/Feds at arms length.>>



Hi Richard,

that is what we like too. Unfortunately there is a link between MAUW and 

stalling speed which is built into the legal definition of an ultralight.If 

you are not an ultralight then you are a light aircraft and you lose all the 

advantages of different licensing rules, medical requirement, self 

maintenance etc.

With the Jabiru fitted to an Extra at MAUW it was not possible to get the 

stall speed low enough to meet the standard required. With the VG`s fitted 

the stalling speed came down  and it is now simply that with VG`s you can be 

a legal ultralight, without them you are not.

Consequently all the testing has now been done by the CAA and now if a kit 

is built to the plans and a Jabiru is fitted it will be cleared for flight.



Pat



do not archive 



--

JetPilot

Joined: 10 Jan 2006
Posts: 1246

Posted: Wed Feb 08, 2006 8:46 am Post subject: Re: VG Installation

 	  Richard Pike wrote: 	
		  

I spent a lot of time and effort moving VG's around on my MKIII, and 

eventually settled on what I felt was optimum. 

	




That is exactly the type of information I am looking for    .  Since Diego and I are both putting VG's on our MK-III's,  can you post what position and angle worked best for you.  Did you make your own, or did you use the landshorter.com VG's ?



I understand that every plane turns out a bit different depending on who builds it, but I think the optimum placement for one MK-III would work well for most MK-III's (assuming the same design of VG..)   Different designs of VG's could result in different placements... Different models of Kolbs could also be different.  But since we are talking MK-III's here I bet as a group we could get pretty close to an optimum standard.



Thanks,

Michael A. Bigelow

_________________
"NO FEAR" - If you have no fear you did not go as fast as you could have !!!

Kolb MK-III Xtra, 912-S

Dennis.Kirby(at)kirtland.
Guest

Posted: Wed Feb 08, 2006 10:19 am Post subject: VG Installation

<< The big question is, has anyone done the testing needed to find out the

optimum placement of VG's for the MK-III, and that I dont know.  Michael A.

Bigelow >>



Michael, and Kolbers contemplating using VGs -



I can answer this question.



In the past nine years I've monitored this Kolb List, I have seen SEVERAL

detailed reports of our Kolbers' experiences with VG placements.  The most

comprehensive analysis I've seen is documented by Richard Pike.  In his

wonderfully informative website, Richard reveals how he experimented with

many different placements of VGs, eventually settling on a configuration

that was ideal for his airplane.  



This was trial-and-error testing in its purest form.  And other Kolbers

(Beauford, Hart, + others) have posted similar reports.  This wealth of

information on the topic of VGs in the archives can save us much trouble

from doing the experimentation all over again.  



I plan to use Rev Pike's VG placement details when I install the LandShorter

VGs on my Mark-III.  And I plan to install 'em only once. 



Dennis Kirby

N93Dk, "Magic Bike"

Cedar Crest, NM

Do not archive

biglar

Joined: 14 Jan 2006
Posts: 457

Posted: Wed Feb 08, 2006 10:51 am Post subject: VG Installation

Well said, Dennis.                    Lar.               Do not Archive.



Larry Bourne

Palm Springs, CA

Building Kolb Mk III

N78LB  Vamoose

www.gogittum.com



---

_________________
Larry Bourne
Palm Springs, CA
Building Kolb Mk IIIC
"Vamoose"

kiwimick

Joined: 10 Jan 2006
Posts: 25
Location: ENGLAND

Posted: Wed Feb 08, 2006 2:13 pm Post subject: VG Installation

John/All,

I would agree that you guys have a much easier/workable system in the USA, 

however we have to bow and scrape and comply with some very strange rules.

We were not trying to re-design Homers wonderful aircraft, we simply had to 

make it comply with UK regs with the use of VG's.

The Landshorter type and the 3" pitch falles right in the valleys between 

the ribs, but they are well back  and not in the deepest portion of the 

valley.

I was most happy with the standard aircraft however my choice of fitting 

VG's to overcome our issue of stall speed was based upon my engineering 

background, test pilot, airworthiness inspector, flight instructor and 

approx 7000hrs of flight experience(of which probably only about 450hrs are 

are in Kolbs).

I am not saying my setup is better than all others, I was just answering a 

question from a fellow Kolber with all the information and data we have 

gathered over the last 18 months of flying and testing VG's.

Maybe the air is different over here or something......



Mike

Xtra/Jab 2200





---

_________________
Mike the kiwi Kolber in England.......

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