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Dennis Kirby
Joined: 05 Dec 2013
Posts: 35
Location: Albuquerque, NM
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 Posted: Mon Mar 10, 2014 7:38 am Post subject: Drag Reduction Paradox |
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Kolb Friends -
Since it's been somewhat slow on the List lately, here's a bizarre flight report outcome that I thought I would share.
In my quest to reduce aerodynamic drag on my Mark-III, it has become apparent that the more I attempt to clean up the airframe, instead of seeing my Kolb go faster, the results are making my airplane SLOWER!
My top speed is unchanged. The typical cruise speed for my 912 Mark-III has always been between 70 and 75 mph true airspeed (at 4800 rpm). But over the last couple of years, as I've added aerodynamic fairings on my gear legs, fairings on the sides of the upper-rear pod area, and a fairing over the top-of-windshield-to-wing juncture, I kept expecting to see my cruise speed pick up a couple of mph. But no.
What's actually happening is my slowest speed just keeps getting slower. Prior to installing the windshield-to-wing fairing, the lowest power setting at which I could fly without losing altitude was 3800 rpm. Any slower, and the Kolb would sink. Now, I can fly at 3400 rpm and still maintain straight and level flight. On my cross-country flights now, I'm not going any faster than before, but I'm burning two-tenths of a gallon less per hour at the same power setting.
A couple of years ago, Thom Riddle posted a flight report where he stated that aerodynamic clean-ups on a Kolb seem to contribute more toward lower fuel burn instead of higher airspeeds, due to improved efficiency. I believe that's what I'm seeing here.
Fine with me. Since most of my flying is local, I'm OK to putter around at low power settings, burning as little fuel as possible. The scenery around the mountains of central New Mexico is always interesting!
Dennis Kirby
Mark-3 / 912ul / Powerfin-72
Sandia Park, NM
do not archive
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John Hauck
Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)
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| Posted: Mon Mar 10, 2014 9:24 am Post subject: Drag Reduction Paradox |
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Dennis K/Kolbers:
I am strictly an amateur and what I share here is strictly my own personal
opinion.
Having built three of my own Kolb aircraft, three different models, I always
shrink the fabric to what I consider the limit, just before it breaks the
airplane. I have always felt that I should try to keep the same shape
airfoil in air as it is on the ground, at rest. Because we are dealing with
a fabric covered wing, it depends on its shape by inner structure and
tautness of the fabric. Loose fabric makes a lot different airfoil that
tight fabric. As tight as the fabric is on my wing, I still get a concave
lower wing surface in flight, but not much. The more concave that surface,
the slower the airplane will fly, but probably kill a lot of top and cruise
speed.
My MKIII has always cruised at 80 mph, or more, calibrated air speed, at
5,000 rpm with a 912, 912ULS, and at 5,800 rpm with a 582. Most Kolbs don't
cruise that fast. I know of only one other MKIII that will, and it is
configured identical to mine. James Trip and I made an 800 sm trip together
a couple years ago. We flew side by side for much of that flight,
confirming that both aircraft were performing identically at cruise.
Basically, we all build a Kolb to nearly identical specification for size
and shape. What makes the difference in performance is how that shape
changes once in the air.
Again, my own opinion, based on a lot of time on a lot of cross country
flights to think about it. 
john h
mkIII
Titus, Alabama
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John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama |
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WhiskeyVictor36(at)aol.co
Guest
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| Posted: Mon Mar 10, 2014 9:27 am Post subject: Drag Reduction Paradox |
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Mr Kirby & Other Kolbers
Quite a few years ago, someone on this list was attempting to accomplish the same thing as you are. Another wise lister responded by saying, " You can't make a Butterfly go Fast".
I assume he was insinuating that Kolbs are like butterflies.
Bill Varnes
Original Kolb FireStar
Audubon NJ
Do Not Archive
In a message dated 3/10/2014 11:38:49 A.M. Eastern Daylight Time, dennis.kirby.3(at)us.af.mil writes:
| Quote: | In my quest to reduce aerodynamic drag on my Mark-III, it has become apparent that the more I attempt to clean up the airframe, instead of seeing my Kolb go faster, the results are making my airplane SLOWER!
|
[quote][b]
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rowedenny
Joined: 09 Mar 2008
Posts: 338
Location: Western PA
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| Posted: Mon Mar 10, 2014 10:20 am Post subject: Drag Reduction Paradox |
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John,
I also wonder if your enclosed rear fuselage helps you and Mr Tripps speeds. I often Think of closing mine up like yours but the wife is against it. I think once I get a bigger fuel tank installed I might over rule her and give it a try.
Dennis "Skid" Rowe
Mk3, 690L-70, Leechburg, PA
[quote] On Mar 10, 2014, at 1:23 PM, "John Hauck" <jhauck(at)elmore.rr.com> wrote:
Dennis K/Kolbers:
I am strictly an amateur and what I share here is strictly my own personal
opinion.
Having built three of my own Kolb aircraft, three different models, I always
shrink the fabric to what I consider the limit, just before it breaks the
airplane. I have always felt that I should try to keep the same shape
airfoil in air as it is on the ground, at rest. Because we are dealing with
a fabric covered wing, it depends on its shape by inner structure and
tautness of the fabric. Loose fabric makes a lot different airfoil that
tight fabric. As tight as the fabric is on my wing, I still get a concave
lower wing surface in flight, but not much. The more concave that surface,
the slower the airplane will fly, but probably kill a lot of top and cruise
speed.
My MKIII has always cruised at 80 mph, or more, calibrated air speed, at
5,000 rpm with a 912, 912ULS, and at 5,800 rpm with a 582. Most Kolbs don't
cruise that fast. I know of only one other MKIII that will, and it is
configured identical to mine. James Trip and I made an 800 sm trip together
a couple years ago. We flew side by side for much of that flight,
confirming that both aircraft were performing identically at cruise.
Basically, we all build a Kolb to nearly identical specification for size
and shape. What makes the difference in performance is how that shape
changes once in the air.
Again, my own opinion, based on a lot of time on a lot of cross country
flights to think about it.
john h
mkIII
Titus, Alabama
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lcottrell
Joined: 29 May 2006
Posts: 1494
Location: Jordan Valley, Or
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| Posted: Mon Mar 10, 2014 5:36 pm Post subject: Drag Reduction Paradox |
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Dennis, I have no idea what your enclosure looks like, so I can't make any guess as to what can help. However when I made my trip with Arty several years ago, I used Kolb's "full enclosure" on my Firestar II so that I could stuff it full of camping stuff. I had the wrap around lexan, and the "convertible" type of flexible fabric that went behind the rear jump seat and in front of the tanks. That configuration cost me 3 MPH.
When I got back I took off the fabric leaving the windshield and making the plane look like a "shuttlecock", but it was faster. The square fabric was causing the drag.
I put streamlined fairings on both my struts and gear legs, and gained about 3 mph each. Then I put bigger wheels on the plane and lost a couple.
I do believe that John's enclosure would give you less drag, I guess its whether it is worth the extra speed is what you will have to decide. I had a Mark III with a full windshield that was open at the back. With a 582 I could never get much more than 63 MPH out of it, and it burned 5 gph. I sold the plane and the guy came over and flew with me, and I had to fly S's patterns in order to not fly off and leave him.
Larry
On Mon, Mar 10, 2014 at 9:28 AM, KIRBY, DENNIS T GS-13 USAF AFMC AFNWC/ENS <dennis.kirby.3(at)us.af.mil (dennis.kirby.3(at)us.af.mil)> wrote:
| Quote: | --> Kolb-List message posted by: "KIRBY, DENNIS T GS-13 USAF AFMC AFNWC/ENS" <dennis.kirby.3(at)us.af.mil (dennis.kirby.3(at)us.af.mil)>
Kolb Friends -
Since it's been somewhat slow on the List lately, here's a bizarre flight report outcome that I thought I would share.
In my quest to reduce aerodynamic drag on my Mark-III, it has become apparent that the more I attempt to clean up the airframe, instead of seeing my Kolb go faster, the results are making my airplane SLOWER!
My top speed is unchanged. The typical cruise speed for my 912 Mark-III has always been between 70 and 75 mph true airspeed (at 4800 rpm). But over the last couple of years, as I've added aerodynamic fairings on my gear legs, fairings on the sides of the upper-rear pod area, and a fairing over the top-of-windshield-to-wing juncture, I kept expecting to see my cruise speed pick up a couple of mph. But no.
What's actually happening is my slowest speed just keeps getting slower. Prior to installing the windshield-to-wing fairing, the lowest power setting at which I could fly without losing altitude was 3800 rpm. Any slower, and the Kolb would sink. Now, I can fly at 3400 rpm and still maintain straight and level flight. On my cross-country flights now, I'm not going any faster than before, but I'm burning two-tenths of a gallon less per hour at the same power setting.
A couple of years ago, Thom Riddle posted a flight report where he stated that aerodynamic clean-ups on a Kolb seem to contribute more toward lower fuel burn instead of higher airspeeds, due to improved efficiency. I believe that's what I'm seeing here.
Fine with me. Since most of my flying is local, I'm OK to putter around at low power settings, burning as little fuel as possible. The scenery around the mountains of central New Mexico is always interesting!
Dennis Kirby
Mark-3 / 912ul / Powerfin-72
Sandia Park, NM
do not archive
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neilsenrm(at)gmail.com
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| Posted: Mon Mar 10, 2014 6:56 pm Post subject: Drag Reduction Paradox |
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I have a VW powered MKIIIC with a full enclosure like Johns. Flying in Michigan I felt it would be warmer. The nicest feature is I can stuff a weeks worth of clothes and food in that enclosure. I put all my camping gear in the passenger seat along with a aux fuel tank and I'm good to go.
My MKIIIC likes to fly at 75 MKH. Yes it will fly faster but it isn't happy. I have flown cross country with four other MKIIICs, two 80HP without enclosures were happy app. 5 MPH faster and one was just a tad slower. John's MKIIIC with enclosure is also faster with 100HP. My big VW hangs out in the wind and may slow it down a bit so is the enclosed Kolb faster????
Rick Neilsen
Redrive VW powered MKIIIC
On Mon, Mar 10, 2014 at 9:36 PM, Larry Cottrell <lcottrell1020(at)gmail.com (lcottrell1020(at)gmail.com)> wrote:
[quote]Dennis, I have no idea what your enclosure looks like, so I can't make any guess as to what can help. However when I made my trip with Arty several years ago, I used Kolb's "full enclosure" on my Firestar II so that I could stuff it full of camping stuff. I had the wrap around lexan, and the "convertible" type of flexible fabric that went behind the rear jump seat and in front of the tanks. That configuration cost me 3 MPH.
When I got back I took off the fabric leaving the windshield and making the plane look like a "shuttlecock", but it was faster. The square fabric was causing the drag.
I put streamlined fairings on both my struts and gear legs, and gained about 3 mph each. Then I put bigger wheels on the plane and lost a couple.
I do believe that John's enclosure would give you less drag, I guess its whether it is worth the extra speed is what you will have to decide. I had a Mark III with a full windshield that was open at the back. With a 582 I could never get much more than 63 MPH out of it, and it burned 5 gph. I sold the plane and the guy came over and flew with me, and I had to fly S's patterns in order to not fly off and leave him.
Larry
On Mon, Mar 10, 2014 at 9:28 AM, KIRBY, DENNIS T GS-13 USAF AFMC AFNWC/ENS <dennis.kirby.3(at)us.af.mil (dennis.kirby.3(at)us.af.mil)> wrote:
| Quote: | --> Kolb-List message posted by: "KIRBY, DENNIS T GS-13 USAF AFMC AFNWC/ENS" <dennis.kirby.3(at)us.af.mil (dennis.kirby.3(at)us.af.mil)>
Kolb Friends -
Since it's been somewhat slow on the List lately, here's a bizarre flight report outcome that I thought I would share.
In my quest to reduce aerodynamic drag on my Mark-III, it has become apparent that the more I attempt to clean up the airframe, instead of seeing my Kolb go faster, the results are making my airplane SLOWER!
My top speed is unchanged. The typical cruise speed for my 912 Mark-III has always been between 70 and 75 mph true airspeed (at 4800 rpm). But over the last couple of years, as I've added aerodynamic fairings on my gear legs, fairings on the sides of the upper-rear pod area, and a fairing over the top-of-windshield-to-wing juncture, I kept expecting to see my cruise speed pick up a couple of mph. But no.
What's actually happening is my slowest speed just keeps getting slower. Prior to installing the windshield-to-wing fairing, the lowest power setting at which I could fly without losing altitude was 3800 rpm. Any slower, and the Kolb would sink. Now, I can fly at 3400 rpm and still maintain straight and level flight. On my cross-country flights now, I'm not going any faster than before, but I'm burning two-tenths of a gallon less per hour at the same power setting.
A couple of years ago, Thom Riddle posted a flight report where he stated that aerodynamic clean-ups on a Kolb seem to contribute more toward lower fuel burn instead of higher airspeeds, due to improved efficiency. I believe that's what I'm seeing here.
Fine with me. Since most of my flying is local, I'm OK to putter around at low power settings, burning as little fuel as possible. The scenery around the mountains of central New Mexico is always interesting!
Dennis Kirby
Mark-3 / 912ul / Powerfin-72
Sandia Park, NM
do not archive
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arget="_blank">http://www.matronics.com/Navigator?Kolb-List
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get="_blank">http://www.matronics.com/Navigator?Kolb-List
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John Hauck
Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)
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| Posted: Mon Mar 10, 2014 7:17 pm Post subject: Drag Reduction Paradox |
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Rick N, Kolbers:
I think it is. My MKIII cruised 80 mph with all three different engines, 912, 912ULS, and the 582. 80 mph is the sweet spot for my airplane. I can cruise 86-88 mph at 5200 rpm and usually fly long cross country flights at that speed. Some of those flights get plenty boring and I get a little anxious to get where I am going.
I think the reason my MKIII flies as well as it does is because of the modifications we made to it, the small frontal area of the 912 series and 582 engines. I think another little trick that helps is the keel fabric fairing which forms a V, instead of the flat belly on the standard MKIII. Also the configuration of my landing gear. There is only 18" of gear leg protruding from the main gear sockets. Braces on the main gear are streamlined 4130. I couldn't tell any difference from flying with 6.00X6 and 8.00X6 tires, and I flew each on individual flights to Alaska. Don't forget my fabric tension. I still think that alone makes a lot of difference over a Kolb that is not as tight.
john h
mkIII
Titus, Alabama
From: owner-kolb-list-server(at)matronics.com [mailto:owner-kolb-list-server(at)matronics.com] On Behalf Of Rick Neilsen
Sent: Monday, March 10, 2014 9:56 PM
To: kolb-list(at)matronics.com
Subject: Re: Drag Reduction Paradox
I have a VW powered MKIIIC with a full enclosure like Johns. Flying in Michigan I felt it would be warmer. The nicest feature is I can stuff a weeks worth of clothes and food in that enclosure. I put all my camping gear in the passenger seat along with a aux fuel tank and I'm good to go.
My MKIIIC likes to fly at 75 MKH. Yes it will fly faster but it isn't happy. I have flown cross country with four other MKIIICs, two 80HP without enclosures were happy app. 5 MPH faster and one was just a tad slower. John's MKIIIC with enclosure is also faster with 100HP. My big VW hangs out in the wind and may slow it down a bit so is the enclosed Kolb faster????
Rick Neilsen
Redrive VW powered MKIIIC
On Mon, Mar 10, 2014 at 9:36 PM, Larry Cottrell <lcottrell1020(at)gmail.com (lcottrell1020(at)gmail.com)> wrote:
Dennis,
I have no idea what your enclosure looks like, so I can't make any guess as to what can help. However when I made my trip with Arty several years ago, I used Kolb's "full enclosure" on my Firestar II so that I could stuff it full of camping stuff. I had the wrap around lexan, and the "convertible" type of flexible fabric that went behind the rear jump seat and in front of the tanks. That configuration cost me 3 MPH.
When I got back I took off the fabric leaving the windshield and making the plane look like a "shuttlecock", but it was faster. The square fabric was causing the drag.
I put streamlined fairings on both my struts and gear legs, and gained about 3 mph each. Then I put bigger wheels on the plane and lost a couple.
I do believe that John's enclosure would give you less drag, I guess its whether it is worth the extra speed is what you will have to decide. I had a Mark III with a full windshield that was open at the back. With a 582 I could never get much more than 63 MPH out of it, and it burned 5 gph. I sold the plane and the guy came over and flew with me, and I had to fly S's patterns in order to not fly off and leave him.
Larry
On Mon, Mar 10, 2014 at 9:28 AM, KIRBY, DENNIS T GS-13 USAF AFMC AFNWC/ENS <dennis.kirby.3(at)us.af.mil (dennis.kirby.3(at)us.af.mil)> wrote:
--> Kolb-List message posted by: "KIRBY, DENNIS T GS-13 USAF AFMC AFNWC/ENS" <dennis.kirby.3(at)us.af.mil (dennis.kirby.3(at)us.af.mil)>
Kolb Friends -
Since it's been somewhat slow on the List lately, here's a bizarre flight report outcome that I thought I would share.
In my quest to reduce aerodynamic drag on my Mark-III, it has become apparent that the more I attempt to clean up the airframe, instead of seeing my Kolb go faster, the results are making my airplane SLOWER!
My top speed is unchanged. The typical cruise speed for my 912 Mark-III has always been between 70 and 75 mph true airspeed (at 4800 rpm). But over the last couple of years, as I've added aerodynamic fairings on my gear legs, fairings on the sides of the upper-rear pod area, and a fairing over the top-of-windshield-to-wing juncture, I kept expecting to see my cruise speed pick up a couple of mph. But no.
What's actually happening is my slowest speed just keeps getting slower. Prior to installing the windshield-to-wing fairing, the lowest power setting at which I could fly without losing altitude was 3800 rpm. Any slower, and the Kolb would sink. Now, I can fly at 3400 rpm and still maintain straight and level flight. On my cross-country flights now, I'm not going any faster than before, but I'm burning two-tenths of a gallon less per hour at the same power setting.
A couple of years ago, Thom Riddle posted a flight report where he stated that aerodynamic clean-ups on a Kolb seem to contribute more toward lower fuel burn instead of higher airspeeds, due to improved efficiency. I believe that's what I'm seeing here.
Fine with me. Since most of my flying is local, I'm OK to putter around at low power settings, burning as little fuel as possible. The scenery around the mountains of central New Mexico is always interesting!
Dennis Kirby
Mark-3 / 912ul / Powerfin-72
Sandia Park, NM
do not archive<![if !supportLineBreakNewLine]><![endif]>
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John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama |
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GeoB
Joined: 16 Jun 2009
Posts: 207
Location: Fresno, CA
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| Posted: Tue Mar 11, 2014 12:37 am Post subject: Drag Reduction Paradox |
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| Quote: | In my quest to reduce aerodynamic drag on my Mark-III
|
I believe I kinda remember a Kolber saying that he gained significant
increase in speed after he streamlined the struts. Have you seen this to be
true? It may have been a Firestar, not sure.
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"Members of Congress should be compelled to wear uniforms like NASCAR drivers, so we could identify their corporate sponsors" |
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John Hauck
Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)
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| Posted: Tue Mar 11, 2014 3:21 am Post subject: Drag Reduction Paradox |
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Was true on my Firestar. I started out with round struts. Then we
fabricated lift strut from streamlined 4130. Was like flying a new
airplane. I had difficulty slowing down on my 600 foot grass strip.
Vibration like the old round struts was gone. Can't remember any numbers.
That was in 1987.
john h
mkIII
Titus, Alabama
| Quote: | In my quest to reduce aerodynamic drag on my Mark-III
|
I believe I kinda remember a Kolber saying that he gained significant
increase in speed after he streamlined the struts. Have you seen this to be
true? It may have been a Firestar, not sure.
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John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama |
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clydemacquarrie(at)eastli
Guest
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| Posted: Tue Mar 11, 2014 4:01 am Post subject: Drag Reduction Paradox |
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In 2011 I started taking flying lessons my Mark 3 with no covering on the
struts. After someone posted the results of lab test done back in the
forties showing the difference with streamlining the struts I was convinced
it was the way to go. I installed the fairings before continuing my training
in 2012 and noticed a big improvement in climb rate and speed.
--------------------------------------------------
From: "George Bearden" <gab16(at)sbcglobal.net>
Sent: Tuesday, March 11, 2014 5:36 AM
To: <kolb-list(at)matronics.com>
Subject: Re: Drag Reduction Paradox
| Quote: |
> In my quest to reduce aerodynamic drag on my Mark-III
I believe I kinda remember a Kolber saying that he gained significant
increase in speed after he streamlined the struts. Have you seen this to
be
true? It may have been a Firestar, not sure.
|
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Richard Pike
Joined: 09 Jan 2006
Posts: 1671
Location: Blountville, Tennessee
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| Posted: Tue Mar 11, 2014 5:52 am Post subject: Re: Drag Reduction Paradox |
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When I put streamline fairings over my aluminum tapered gear legs, I noticed an immediate change in trim, the airplane wanted to fly more nose up, presumably because of the reduction in gear leg drag well below the center of drag.
Have converted over to the very old style machined and tapered steel gear legs which Kolb has not sold in years, but have not yet flown with them. They are substantially slimmer than the aluminum gear legs, but also a bit longer. Will be interesting to see if the trim changes.
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Richard Pike
Kolb MKIII N420P (420ldPoops)
Kingsport, TN 3TN0
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ceengland7(at)gmail.com
Guest
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| Posted: Tue Mar 11, 2014 7:08 am Post subject: Drag Reduction Paradox |
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On 3/11/2014 3:36 AM, George Bearden wrote:
| Quote: |
> In my quest to reduce aerodynamic drag on my Mark-III
I believe I kinda remember a Kolber saying that he gained significant
increase in speed after he streamlined the struts. Have you seen this to be
true? It may have been a Firestar, not sure.
The difference in round vs streamlined is *huge*. There's a drawing
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that's floating around the net showing the equivalent cross sections of
a wire, a square rod, a streamline profile, etc that is almost
unbelievable. I couldn't find it with a quick search, but I did find a
link to an old Sport Aviation article (back when they had articles for
homebuilders).
Note carefully the decimal point locations.
file:///C:/Users/Charlie/Downloads/Streamline_SAA.pdf
Charlie
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Richard Pike
Joined: 09 Jan 2006
Posts: 1671
Location: Blountville, Tennessee
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| Posted: Tue Mar 11, 2014 12:32 pm Post subject: Re: Drag Reduction Paradox |
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| ceengland7(at)gmail.com wrote: | On 3/11/2014 3:36 AM, George Bearden wrote:
| Quote: |
> In my quest to reduce aerodynamic drag on my Mark-III
I believe I kinda remember a Kolber saying that he gained significant
increase in speed after he streamlined the struts. Have you seen this to be
true? It may have been a Firestar, not sure.
The difference in round vs streamlined is *huge*. There's a drawing
|
that's floating around the net showing the equivalent cross sections of
a wire, a square rod, a streamline profile, etc that is almost
unbelievable. I couldn't find it with a quick search, but I did find a
link to an old Sport Aviation article (back when they had articles for
homebuilders).
Note carefully the decimal point locations.
file:///C:/Users/Charlie/Downloads/Streamline_SAA.pdf
Charlie |
Um - Charlie? I don't think that's a web url - I think it's a file on your hard drive.
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_________________
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kingsport, TN 3TN0
Forgiving is tough, being forgiven is wonderful, and God's grace really is amazing. |
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ceengland7(at)gmail.com
Guest
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| Posted: Tue Mar 11, 2014 3:53 pm Post subject: Drag Reduction Paradox |
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On 3/11/2014 3:32 PM, Richard Pike wrote:
| Quote: |
ceengland7(at)gmail.com wrote:
> On 3/11/2014 3:36 AM, George Bearden wrote:
>
>>
>>
>>> In my quest to reduce aerodynamic drag on my Mark-III
>> I believe I kinda remember a Kolber saying that he gained significant
>> increase in speed after he streamlined the struts. Have you seen this to be
>> true? It may have been a Firestar, not sure.
>>
>>
>> The difference in round vs streamlined is *huge*. There's a drawing
>>
> that's floating around the net showing the equivalent cross sections of
> a wire, a square rod, a streamline profile, etc that is almost
> unbelievable. I couldn't find it with a quick search, but I did find a
> link to an old Sport Aviation article (back when they had articles for
> homebuilders).
> Note carefully the decimal point locations.
>
> file:///C:/Users/Charlie/Downloads/Streamline_SAA.pdf
>
> Charlie
Um - Charlie? I don't think that's a web url - I think it's a file on your hard drive.
--------
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kingsport, TN 3TN0
My soul shall be joyful in the LORD; It shall rejoice in His salvation. Psalm 35:9
Uhhhh, oops. The link does indeed require a download of a pdf file,
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which then opened automatically in my web browser (chrome). I made the
mistake of copying the url line & failed to notice that it pointed to
the downloaded file instead of the site. It's actually on the Matronics
server, but it's through the forum & I use regular email. Try this
rather nasty link:
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0CC4QFjAB&url=http%3A%2F%2Fforums.matronics.com%2Fdownload.php%3Fid%3D12887%26sid%3D329d1844c4ac0988dc9552b9aed282b2&ei=-iQfU_ihFIfukQf7zYHACA&usg=AFQjCNFj7FR4iMleClzW5i3rcXQrdvynyg&sig2=2iAaS9k5dhi0fiG73RMRqA
Charlie
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jbhart(at)onlyinternet.ne
Guest
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| Posted: Wed Mar 12, 2014 11:00 am Post subject: Drag Reduction Paradox |
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At 01:32 PM 3/11/2014 -0700, you wrote:
| Quote: |
--------
Richard Pike
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Could this be what you are looking for?
http://www.jackbhart.com/firefly/pdrag.html
Jack B. Hart FF004
Winchester, IN
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Arizona Flyer
Joined: 09 May 2013
Posts: 31
Location: Casa Grande Arizona
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| Posted: Wed Mar 12, 2014 11:03 am Post subject: Re: Drag Reduction Paradox |
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Also waxing your airplane will increase efficiency & speed. On my Rans S-7 after I put wax on I gained 3 to 5 mph at cruise & top speed.
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"Life should be lived as a bold adventure, I refuse to tiptoe through life just to arrive safely at death" |
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smlplanet(at)msn.com
Guest
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| Posted: Wed Mar 12, 2014 11:25 am Post subject: Drag Reduction Paradox |
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I haven't noticed any one saying any thing about vortex generators to help performance. I have a Mark 111 / 912 80hp with the enclosed rear area, fairing on the struts, steel landing gear with tundra tires. After installing the vortex generators I noticed a lower stall speed, increase in cruising speed and climb. There was also a decrease in fuel usage both solo and duel. My main reason for installing them was the short field and beach landing and take off...less roll out and was surprised by the above added advantages.
| Quote: | Subject: Re: Drag Reduction Paradox
From: heracesthesun(at)yahoo.com
Date: Wed, 12 Mar 2014 12:03:48 -0700
To: kolb-list(at)matronics.com
--> Kolb-List message posted by: "Arizona Flyer" <heracesthesun(at)yahoo.com>
Also waxing your airplane will increase efficiency & speed. On my Rans S-7 after I put wax on I gained 3 to 5 mph at cruise & top speed.
--------
"Life should be lived as a bold adventure, I refuse to tiptoe through life just to arrive safely at death"
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=420213#420213
====
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Richard Pike
Joined: 09 Jan 2006
Posts: 1671
Location: Blountville, Tennessee
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| Posted: Wed Mar 12, 2014 8:39 pm Post subject: Re: Drag Reduction Paradox |
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| smlplanet(at)msn.com wrote: | I haven't noticed any one saying any thing about vortex generators to help performance. I have a Mark 111 / 912� 80hp with the enclosed rear area, fairing on the struts, steel landing gear with tundra tires.� After installing the vortex generators I noticed a lower stall speed, increase in cruising speed and climb. There was also a decrease in fuel usage both solo and duel.� My main reason for installing them was the short field and beach landing and take off...less roll out and was surprised by the above added advantages.
|
Yep. My experience exactly. Isn't it wonderfully simple and straightforward?
Enjoy.
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_________________
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kingsport, TN 3TN0
Forgiving is tough, being forgiven is wonderful, and God's grace really is amazing. |
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ThermalHunter
Joined: 13 Dec 2012
Posts: 9
Location: Cleveland, TN
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| Posted: Thu Mar 13, 2014 1:42 am Post subject: Drag Reduction Paradox |
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Ref> Vortex Generators (VG's)... just installed them on my Firestar (43 on each wing) and the first thing I noticed was increased climb rate and better control at low-speed touchdowns (lowered stall speed combined with better handling is a win-win). Don't know about an increase in cruise speed, just learned that drag is not a factor at higher speeds.
Robert Gillisse
2004 Kolb Firestar II
503 DCDI
Collegedale, TN
On Thursday, March 13, 2014 12:44 AM, Richard Pike <richard(at)bcchapel.org> wrote:
--> Kolb-List message posted by: "Richard Pike" <richard(at)bcchapel.org (richard(at)bcchapel.org)>
smlplanet(at)msn.com wrote:
| Quote: | I haven't noticed any one saying any thing about vortex generators to help performance. I have a Mark 111 / 912� 80hp with the enclosed rear area, fairing on the struts, steel landing gear with tundra tires.� After installing the vortex generators I noticed a lower stall speed, increase in cruising speed and climb. There was also a decrease in fuel usage both solo and duel.� My main reason for installing them was the short field and beach landing and take off...less roll out and was surprised by the above added advantages.
|
Yep. My experience exactly. Isn't it wonderfully simple and straightforward?
Enjoy.
--------
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kingsport, TN 3TN0
My soul shall be joyful in the LORD; It shall rejoice in His salvation. Psalm 35:9
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=420251#420251ht -Matt Dralle, List ion" =======
[quote][b]
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pj.ladd(at)btinternet.com
Guest
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| Posted: Thu Mar 13, 2014 3:49 am Post subject: Drag Reduction Paradox |
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<<just learned that drag is not a factor at higher speeds. >>
Huh!,
I thought drag increased by the square of the speed (or something like that) In essence the faster you go the MORE drag you create..
Pat
[quote][b]
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