---------------------------------------------------------- Kolb-List Digest Archive --- Total Messages Posted Mon 02/18/08: 26 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 01:38 AM - Re: Re: Finally flying my MK III!!! (pj.ladd) 2. 04:07 AM - Hall ASI (william sullivan) 3. 06:32 AM - Re: Hall ASI (possums) 4. 06:49 AM - Re: Vg's (Eugene Zimmerman) 5. 07:03 AM - Re: Vg's (John Hauck) 6. 07:07 AM - Re: Re: Finally flying my MK III!!! (John Hauck) 7. 08:28 AM - Re: Re: Finally flying my MK III!!! (Richard & Martha Neilsen) 8. 09:05 AM - Re: Vg's (Bob Noyer) 9. 09:37 AM - Re: Vg's (beauford T) 10. 10:23 AM - Re: Finally flying my MK III!!! (Rex Rodebush) 11. 11:14 AM - Re: Vg's (Ralph B) 12. 11:37 AM - New topics (Richard Girard) 13. 12:49 PM - VG's : Vortex Generators Testing, Results, and Reports (JetPilot) 14. 01:22 PM - Re: VG's : Vortex Generators Testing, Results, and Reports (Jim Kmet) 15. 01:23 PM - Re: New topics (Mike Welch) 16. 03:01 PM - Re: New topics (grantr) 17. 03:17 PM - The Kolb drop (Richard Girard) 18. 04:05 PM - Re: The Kolb drop (John Hauck) 19. 05:32 PM - Re: VG's : Vortex Generators Testing, Results, and Reports (TK) 20. 05:45 PM - Re: The Kolb drop (Dana Hague) 21. 06:44 PM - Wings and their characteristics (Mike Welch) 22. 06:52 PM - Re: The Kolb drop (Steven Green) 23. 07:10 PM - Re: The Kolb drop (John Hauck) 24. 07:15 PM - Re: The Kolb drop (Bob Noyer) 25. 07:30 PM - Re: Wings and their characteristics (Richard Girard) 26. 08:32 PM - Re: Re: Test email (Ron) ________________________________ Message 1 _____________________________________ Time: 01:38:13 AM PST US From: "pj.ladd" Subject: Re: Kolb-List: Re: Finally flying my MK III!!! VGs likely help but don't help as much as you are being led to believe. In a recent side by side fly off the difference wasn't real noticeable.>> Hi Rick, on this side of the pond the engineering department of the PFA carried out very stringent tests and the answer as far as stall speed is concerned is `They work`. The proof is that the Xtra would not make the stalling speed required to qualify as a `microlight` without the VG`s. With the VG`s fitted it dropped the stalling speed by enough to enable the Xtra to make the grade. Any further so called benefits in cruise and handling are pretty sibjective I think but the lowering of the stall speed is unquestionable. Here you will not get a Certificate to Fly without the VG`s fitted. Cheers Pat ________________________________ Message 2 _____________________________________ Time: 04:07:21 AM PST US From: william sullivan Subject: Kolb-List: Hall ASI Possum- I looked at the photo you sent of the Hall ASI, and noticed something at the top of the nose cone. What is it? Chrome mount with a black thing. What model Kolb is it? Keep in mind that I am a beginner. Teach me. Bill FS do not archive ________________________________ Message 3 _____________________________________ Time: 06:32:06 AM PST US From: possums Subject: Re: Kolb-List: Hall ASI At 07:04 AM 2/18/2008, you wrote: >Possum- I looked at the photo you sent of the Hall ASI, and noticed >something at the top of the nose cone. What is it? Chrome mount with >a black thing. What model Kolb is it? > Keep in mind that I am a beginner. Teach me. > Bill > FS >do not archive Ahhhh, a new FNG ! This thing? It tells me the way the wind is blowing, if it ever points straight back at me while I am flying the plane, I pull the little red handle next to the seat. Actually - it is a very accurate slip indicator for flying through small gaps in trees & stuff like that that you're not supposed to do. http://video.google.com/videoplay?docid=-8558932262133094065&hl=en ________________________________ Message 4 _____________________________________ Time: 06:49:16 AM PST US From: Eugene Zimmerman Subject: Re: Kolb-List: Vg's On Feb 17, 2008, at 11:50 PM, Richard Girard wrote: > If anyone out there does decide to try the VG's on one wing test, > may I suggest you read the book, "Anatomy of a Spin" by John Lowery > first. > > Rick >>>As for a true apples to apples VG test we need to have this settled once and for all by having a well seasoned kolb pilot try slow flight to stall with VG's on just one wing. < g > <<< Hey guys, Please notice what I said, I said ,,,,,, a "well seasoned " ,,,, kolb pilot ,,,,, and please also notice WHO I wrote that too ; ^) ,,,,,, and please notice the ,,,,, < g >. I'm sure the degree of my seriousness in that idea was not lost on John, and If anybody were actually able to pull it off I'm sure it would be none other than John. So if you are NOT John Hauck ,,,,,,, please DO NOT ever try my DANGEROUS test suggestion. Eugene Zimmerman ________________________________ Message 5 _____________________________________ Time: 07:03:39 AM PST US From: "John Hauck" Subject: Re: Kolb-List: Vg's > So if you are NOT John Hauck ,,,,,,, please DO NOT ever try my > DANGEROUS test suggestion. > > > Eugene Zimmerman Gene Z: I relinquished my "test pilot" duties some time back. Nothing like flying something tried and true. The old mkIII is like putting on an old pair of work boots. john h mkIII ________________________________ Message 6 _____________________________________ Time: 07:07:05 AM PST US From: "John Hauck" Subject: Re: Kolb-List: Re: Finally flying my MK III!!! > Your catchy little one liner is nothing more than an attempt to distract readers from the facts here. All Rick has here is some very biased opinions, and has done nothing short of mislead and misrepresent the facts to make his point. Look at the pictures, look at the facts, and then make your choice. > > Mike Bigelow Mike B: Rick Neilsen was on the ground at London observing the flyoff between Richard Pike and me. His comments are not biased opinions, and he is not trying to mislead and misrepresent the facts to make his point. I flew as slow as Rev Pike with a mkIII that was "probably" much heavier than his mkIII equipped with VG's. Was Richard distracted? Hell, I don't know, or do I understand why that would have anything to do with his minimum flight speed. The wings are going to fly until they quit, whether you are having a good day or bad. I am extremely happy you have a static source for your airspeed indicator. All ASI's have them, although most are not calibrated. If they are not calibrated, they are not very accurate. Takes very little static pressure error to kick one +10 or -10 mph. Your photo is very impressive. If, in fact, your mkIIIx will fly 25 mph straight and level, I congratulate you, because it is probably the only one in existence that will fly that slow. Again, I am not saying VG's do not work. I am saying whatever improvement there is is not justification for me to install them on my airplane. john h mkIII ________________________________ Message 7 _____________________________________ Time: 08:28:20 AM PST US From: "Richard & Martha Neilsen" Subject: Re: Kolb-List: Re: Finally flying my MK III!!! Mike I will only respond this once on this issue only because of your continued inference about the flying qualities of a Kolb. "Kolb Quit" is a "stall" caused by low speed landings in a very low mass airplane. This is what makes our Kolbs superior STOL airplanes. If one follows common GA pilot training with the use of flaps and no power in landing you are right Kolbs take a high skill level to keep from bending gear. If we change our technique by add some speed and power while landing, Kolbs become a very forgiving airplanes to land correctly. Granted it is best to land without having to depend on power and maybe slower speeds but slowly progress to that stage as you get more proficient in your Kolb. As for the VG thing. At some point I will put them on my plane. I think they help and as I get older I might need the help but I'm still concerned about them lowering my cruise speeds. With that said the benefits are considerably over stated on this list. A ham fisted pilot will still bend his landing gear or worse even with VGs. Mike keeps saying I ignore the "facts". Most of us are aware that there is a considerable inaccuracy in airspeed indicators in different airplanes especially between installations and measurement types. To show a photo of a ASI and call it "fact" is a bit of a stretch. I REALLY REALLY don't want to start another VG battle again on the list but. I was there at the VG fly off and saw the drastic differences between the two planes and pilots. There would have been 100% agreement between every one there except maybe John H that he was going to get his butt kicked big time before the fly off. It didn't happen, it was a draw.Yes I heard ALL of the excuses but if VGs help as much as you guys say is "fact" it still would have been a butt kicking. One final comment that is truly quantifiable is that John's non VG airplane weighed almost 25% more!!! OK. Mike I know you, like my wife, will have to have the last word so have at it. Rick Neilsen Redrive VW powered MKIIIC ----- Original Message ----- From: "JetPilot" Sent: Monday, February 18, 2008 1:56 AM Subject: Kolb-List: Re: Finally flying my MK III!!! > > > NeilsenRM(at)comcast.net wrote: >> Grant >> >> VGs likely help but don't help as much as you are being led to believe. >> In a >> recent side by side fly off the difference wasn't real noticeable. >> > > > The pilot flying with the VG's was distracted, and did not fly the plane > well, which he admitted here on the list. You statement here is nothing > short of misleading and bordering on dishonest. Also, not all VG's > installations are equal. VG's made out of alumimum with the " That looks > about right" technique might not work as well. Placement and angles are > VERY critical, if VG's were not installed in a very precise and accurate > manner, their effects will be drastically reduced. > > > NeilsenRM(at)comcast.net wrote: >> >> >> John H correctly made a point that airspeed indicators in Kolbs can be >> inaccurate and at higher angles of attack they get even more so. >> >> > > > Did you not read my post, I have a separate static source and back up the > airspeed with GPS as can be seen in my picture, again your statement is > nothing short of misrepresenting the facts to make your point. Look at > the attached picture and try to explain the GPS speed as instrument error. > > > NeilsenRM(at)comcast.net wrote: >> >> >> The term I hear "kolb quit" is plain and simple a stall no matter how >> much >> these newbies want to believe otherwise. >> No I don't have VGs. Three point landings are easer >> for me and I land slower so.... >> >> As usual the advice is worth what you paid for it. >> >> Rick Neilsen >> Redrive VW powered MKIIIC >> >> >> --- > > > Kolb quit is a very real fact, and it bends a lot of gear on landing. > VG's practically eliminate this bad behavior. I dont care what theory > may or not apply, I would rather have my Kolb land in a docile manner, and > be forgiving of less than perfect technique. Pilots are human, from time > to time you will have a bad landing, I dont want an airplane that will > bite me and be easily damaged on a less than perfect landing. > > > NeilsenRM(at)comcast.net wrote: >> >> >> As usual the advice is worth what you paid for it. >> >> > > > There is a huge amount of evidence and testimonials on the positive effect > VG's here on the list. I have not always had VG's, I have flown my plane > with and without them, and I am giving my results backed up with pictures > and numbers. I do not sell VG's, and I have no reason to mislead anyone > here. I am posting information on VG's here because some Kolbers took the > trouble to tell me about the benefits of VG's, so im passing it along to > others that can benefit also. > > Your catchy little one liner is nothing more than an attempt to distract > readers from the facts here. All Rick has here is some very biased > opinions, and has done nothing short of mislead and misrepresent the facts > to make his point. Look at the pictures, look at the facts, and then make > your choice. > > Mike Bigelow > > -------- > "NO FEAR" - If you have no fear you did not go as fast as you > could have !!! > > Kolb MK-III Xtra, 912-S > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=164760#164760 > > > Attachments: > > http://forums.matronics.com//files/aerialultralightkolbmikeperformancefloridahomestead07_09_2007_009_633.jpg > > > ________________________________ Message 8 _____________________________________ Time: 09:05:55 AM PST US From: Bob Noyer Subject: Re: Kolb-List: Vg's At last we now have a dagger to put through the heart of SeaFoam: VGs! regards, Bob N. FireFly 070 Old Kolb http://www.angelfire.com/rpg/ronoy/ do not archive ________________________________ Message 9 _____________________________________ Time: 09:37:00 AM PST US From: "beauford T" Subject: Re: Kolb-List: Vg's ....what's Seafoam.....? beauford do not archive ----- Original Message ----- From: Bob Noyer To: kolb-list@matronics.com Sent: Monday, February 18, 2008 11:56 AM Subject: Re: Kolb-List: Vg's At last we now have a dagger to put through the heart of SeaFoam: VGs! regards, Bob N. FireFly 070 Old Kolb http://www.angelfire.com/rpg/ronoy/ do not archive ________________________________ Message 10 ____________________________________ Time: 10:23:33 AM PST US Subject: Kolb-List: Re: Finally flying my MK III!!! From: "Rex Rodebush" Sorry. Two different airplanes (even though both are Kolbs) with two different pilots. The VG fly off was interesting but hardly a definitive determination about the effectiveness of V.G.s. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=164837#164837 ________________________________ Message 11 ____________________________________ Time: 11:14:01 AM PST US Subject: Kolb-List: Re: Vg's From: "Ralph B" beauford173(at)verizon.ne" > ....what's Seafoam.....? > > beauford > do not archive > --- ..... maybe I need some VG's to go along with my Seafoam .... :P do not archive -------- Ralph B Original Firestar N91493 E-AB 21 years flying it Read this topic online here: http://forums.matronics.com/viewtopic.php?p=164842#164842 ________________________________ Message 12 ____________________________________ Time: 11:37:27 AM PST US From: "Richard Girard" Subject: Kolb-List: New topics So the list gets a notice from Grant R. that he's finally flown his Mk III and how excited and happy he is to have finally reached this point. He gets a few messages of congratulations, then the argument over VG's devolves along its usual path into name calling and finger pointing, all under the same heading. I don't care much about either side of this argument, but what I would respectfully request is that when you are going to go into this argumentative mode you do the rest of us a favor and simply change the subject line. Is that so hard to do? I fully realize I'm not innocent of this, but I am trying to do better. It seems rather sad that useful information gets plastered with useless tirades. It also makes it particularly difficult to do a search of the archives without coming up with a bunch of garbage rather than the information sought. Just my opinion, you'ze guys will do as you please. Rick do not archive ________________________________ Message 13 ____________________________________ Time: 12:49:01 PM PST US Subject: Kolb-List: VG's : Vortex Generators Testing, Results, and Reports From: "JetPilot" It is nothing short of incredible to me that any rational, intelligent individual would ignore 50 + years of scientific testing and huge number of pilot reports on the benefits of VG's on their Kolbs, based on one test that one of the pilots very clearly stated did not go well. The only thing this tells me is that some individuals have stated their beliefs publicly on the list, and are now so unwilling to admit that they have been wrong, that they ignore mountains of evidence and and cling to one test that was flown very poorly. See report here: http://forums.matronics.com/viewtopic.php?t=32973&highlight=vgs To give bad and incorrect advice here on the list just because a couple of you have so thoroughly dug yourselves into a position and now need to save face is a disservice to everyone that reads this list. Here on the Kolb list we have way to many guys that are so interested in saving face, or backing up their friends in their little " clique ", that they forget about or ignore the truth. Information we publish here on the list not about WHO is right, it is about WHAT is right. Many people read this list to make their airplanes safer and more enjoyable, we owe it to them to post good and accurate information. Mike -------- "NO FEAR" - If you have no fear you did not go as fast as you could have !!! Kolb MK-III Xtra, 912-S Read this topic online here: http://forums.matronics.com/viewtopic.php?p=164865#164865 ________________________________ Message 14 ____________________________________ Time: 01:22:42 PM PST US From: "Jim Kmet" Subject: Re: Kolb-List: VG's : Vortex Generators Testing, Results, and Reports Allright, enough! I can`t bite my tongue anymore! If it is so awfull the way we conduct ourselves, are`nt you ashamed to be a part of this list? If I felt the way you did, I would unsubscribe this list & join another! This is getting "OLD" even for us lurkers. Thank God & Bill Gates for the delete button!! I appreciate both opinions & facts, & I believe rational people have enough sense to filter out works for them & what doesn`t.. Thanks to those who have provided input to my questions & then left it alone. Maybe I`ll rejoin This forum at some later date, but for now, addios! Jim ----- Original Message ----- From: "JetPilot" Sent: Monday, February 18, 2008 2:46 PM Subject: Kolb-List: VG's : Vortex Generators Testing, Results, and Reports > > It is nothing short of incredible to me that any rational, intelligent > individual would ignore 50 + years of scientific testing and huge number > of pilot reports on the benefits of VG's on their Kolbs, based on one > test that one of the pilots very clearly stated did not go well. > > The only thing this tells me is that some individuals have stated their > beliefs publicly on the list, and are now so unwilling to admit that they > have been wrong, that they ignore mountains of evidence and and cling to > one test that was flown very poorly. See report here: > > http://forums.matronics.com/viewtopic.php?t=32973&highlight=vgs > > To give bad and incorrect advice here on the list just because a couple of > you have so thoroughly dug yourselves into a position and now need to save > face is a disservice to everyone that reads this list. Here on the Kolb > list we have way to many guys that are so interested in saving face, or > backing up their friends in their little " clique ", that they forget > about or ignore the truth. > > Information we publish here on the list not about WHO is right, it is > about WHAT is right. Many people read this list to make their airplanes > safer and more enjoyable, we owe it to them to post good and accurate > information. > > Mike > > -------- > "NO FEAR" - If you have no fear you did not go as fast as you > could have !!! > > Kolb MK-III Xtra, 912-S > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=164865#164865 > > > ________________________________ Message 15 ____________________________________ Time: 01:23:55 PM PST US From: Mike Welch Subject: RE: Kolb-List: New topics Poignantly stated, Rick, but likely ignored by a select few. It IS very important, as Rick said, to stay on topic. What is also important is not arguing endlessly about something there not likely a true solution to. This list offers a very valuable resource to those of us seeking assistance. Reading posts that demean or insult do not further the cause of this forum's main objective.....fellowship with like-minded pilots. Grant, I envy your bragging rights!! I long for the day I, too, can solo in my own Kolb MkIII. (Soon, I hope!!)Congradulations from most of us on a wonderful accomplishment!! Mike Welch Kolb MkIII ________________________________ From: jindoguy@gmail.com Subject: Kolb-List: New topics So the list gets a notice from Grant R. that he's finally flown his Mk III and how excited and happy he is to have finally reached this point. He gets a few messages of congratulations, then the argument over VG's devolves along its usual path into name calling and finger pointing, all under the same heading. I don't care much about either side of this argument, but what I would respectfully request is that when you are going to go into this argumentative mode you do the rest of us a favor and simply change the subject line. Is that so hard to do? I fully realize I'm not innocent of this, but I am trying to do better. It seems rather sad that useful information gets plastered with useless tirades. It also makes it particularly difficult to do a search of the archives without coming up with a bunch of garbage rather than the information sought. Just my opinion, you'ze guys will do as you please. Rick do not archive _________________________________________________________________ Shed those extra pounds with MSN and The Biggest Loser! http://biggestloser.msn.com/ ________________________________ Message 16 ____________________________________ Time: 03:01:24 PM PST US Subject: Kolb-List: Re: New topics From: "grantr" Mike, I didn't solo I just flew it with the instructor. I have soloed a Cessna 152 back in 1999 so its been a while 9 years since I flew a plane. The VG debate is just one of those forum things. Every forum I am a member of gets into heated debates over little things that are pointless to argue over. I guess we get bore sometimes and get a Little carried away. :D So y'all don't get your panties in a wad over VGs! [Laughing] Read this topic online here: http://forums.matronics.com/viewtopic.php?p=164887#164887 ________________________________ Message 17 ____________________________________ Time: 03:17:58 PM PST US From: "Richard Girard" Subject: Kolb-List: The Kolb drop I have been the victim of the Kolb "drop" more times than I care to admit. As I've said here before my intimate friendship with Mr. Hydraulic Press didn't end until Travis gave me the advice to wheel it on rather than trying to three point it. Now I carry 3000 RPM (750 prop RPM) all the way down to the deck then cut power and let her settle. It's pretty much the same technique I was taught for the Cessna 182. Works every time. Okay that and nerf tires work every time.;-) So why does the Kolb (I can only speak of the Mk IIIC) have such an abrupt stall break? I'm no aerodynamicist, but I can read a data plot of lift, drag, and center of pressure travel against angle of attack and I'll hazard a semi-educated opinion. It's the leading edge radius and the flat bottom of the airfoil. The Kolb airfoil is about 12% thickness. Some have commented that it is of the TLAR variety and they may well be right. But if you pick up a copy of Michael Rice's little book, "Handbook of Airfoil Sections for Light Aircraft", there are several sections that closely resemble the Kolb's. Take a look at the NACA 66 of 1921 vintage. While the lift coefficient has a fairly gentle curve, the drag rise is very steep as it approaches stalling angle (figure 14 degrees AoA as the point where it most likely stalls) and look at the center of pressure curve, it's moving backward toward 40% as AoA increases, just as it would if you were holding the Kolb off by bringing the stick further and further back. The result. Probably wham, and a visit with Mr. Press. Also take a look at the air speed at which the data was plotted, 98.4 feet per second (67.1 mph). Quite a bit faster than the generally agreed upon touch down speed of the Mk IIIC. No leading edge radius is given for the section, but its bottom is flat from 2.5 % of chord on back. By comparison the Kolb Mk III leading edge is 1.25% of chord (assuming a chord of 60" rather than counting the whole 64" as the aileron and flap leading edge thicken and lengthen out considerably) There's also the Clark Z from 1923. Similar to the NACA 66, but a slightly larger leading edge radius. This section was tested at 58.7 feet per second (40MPH) which is getting closer to the Kolb's drop speed ;-), but look at the lift coefficient plot, it drops like a rock at 16 1/2 degrees AoA. Unfortunately there is no center of pressure plot for this section. If you want to go a bit farther afield, English investigators tested the Fage and Collins 3 in 1927 at 75 feet per second (51.2 mph). It's lift peaks at a bit more than 12 degrees and it's leading edge radius is a bit smaller than the Kolb's at .83%. The German's offer the Goettingen 285 and 365. Both are flat bottomed but the 285 has a larger leading edge radius and was tested at the slowest airspeed of the lot at 29.3 feet per second (20 mph). Unfortunately all it's data plots end at 15 degrees AoA. The 365 had a small leading edge radius that is very close to the Kolb's at 1.26%, but like the NACA 66 it was tested at 98.4 feet per second (67.1 mph) Both these sections were of 1918/1919 vintage. I also looked in Abbot and Von Doenhoff's "Theory of Wing Sections", but it deals with research from the late 20's to the late 40's and there are no flat bottomed sections listed. So, draw your own conclusions, do some more extensive research, or look around at the planes on the ramp the next time you go out to fly. It's not magic why the Kolb drops, but that's just my opinion. Rick do not archive ________________________________ Message 18 ____________________________________ Time: 04:05:31 PM PST US From: "John Hauck" Subject: Re: Kolb-List: The Kolb drop Rick G: Pretty simple solution to Kolb QUIT. Doesn't require a text book to understand. Learn to fly the airplane. Every Kolb model I have flown, over the years, lands the same way, with or without power, with or without flaps. Learn to stall the airplane on the ground or a couple inches above the ground. Or.............fly the airplane to the ground, stick it there, and stop it. Most important is learn to fly it. john h mkIII So, draw your own conclusions, do some more extensive research, or look around at the planes on the ramp the next time you go out to fly. It's not magic why the Kolb drops, but that's just my opinion. Rick ________________________________ Message 19 ____________________________________ Time: 05:32:15 PM PST US From: TK Subject: Re: Kolb-List: VG's : Vortex Generators Testing, Results, and Reports JetPilot wrote: > > It is nothing short of incredible to me that any rational, intelligent individual would ignore 50 + years of scientific testing and huge number of pilot reports on the benefits of VG's on their Kolbs, based on one test that one of the pilots very clearly stated did not go well. > > The only thing this tells me is that some individuals have stated their beliefs publicly on the list, and are now so unwilling to admit that they have been wrong, that they ignore mountains of evidence and and cling to one test that was flown very poorly. See report here: > > http://forums.matronics.com/viewtopic.php?t=32973&highlight=vgs > > To give bad and incorrect advice here on the list just because a couple of you have so thoroughly dug yourselves into a position and now need to save face is a disservice to everyone that reads this list. Here on the Kolb list we have way to many guys that are so interested in saving face, or backing up their friends in their little " clique ", that they forget about or ignore the truth. > > Information we publish here on the list not about WHO is right, it is about WHAT is right. Many people read this list to make their airplanes safer and more enjoyable, we owe it to them to post good and accurate information. > > Mike > > -------- > "NO FEAR" - If you have no fear you did not go as fast as you could have !!! > > Kolb MK-III Xtra, 912-S > Mike, I don't know how this Kolb List was ever able to function before you came along. I do know that it was a much more pleasant place to visit before. Seems like every year or so, a new self-righteous individual comes along and plays havoc with the list. I only wish I was as certain of my perfect insight into what is right and wrong as you seem to be. With your constant ravings we are slowly losing the quality of this group and the individuals that made it a good thing. Must be a generational thing for it seems that "some newcomers" are infected with the missionary zeal of being the only one's who can see the truth! Who are you going to insult and rave at when there is no one else left? When you have proven yourself with many years of experience with a Kolb, come back and tell us all about it in a civil and respectful manner!! How many hours did you say you have?!!!!!!!! How many other groups have you infected over the years?!!!! Terry - FireFly #95 ________________________________ Message 20 ____________________________________ Time: 05:45:08 PM PST US From: Dana Hague Subject: Re: Kolb-List: The Kolb drop At 06:15 PM 2/18/2008, Richard Girard wrote: >...It's the leading edge radius and the flat bottom of the airfoil. The >Kolb airfoil is about 12% thickness... Any airfoil with a fairly sharp leading edge will have an fairly abrupt stall. The flat bottom is irrelevant; it's just the product of the taper and thickness distribution (though like the leading edge chosen, no doubt, for ease of construction). Combine the abrupt stall with a low mass / high drag aircraft and you get the behavior you see. You don't want to flare too soon or high with a Quicksilver, either, or you'll be straightening or replacing the landing gear downtubes (been there, done that... once). The test speeds for the other airfoils you mention has nothing to do with it (except perhaps for some minor Reynolds number effects). -Dana -- The speed of light is greater than the speed of sound. That's why some people seem very bright until you hear them speak. ________________________________ Message 21 ____________________________________ Time: 06:44:50 PM PST US From: Mike Welch Subject: Kolb-List: Wings and their characteristics You'ze guys, I don't begin to have all the facts about airfoils like Rick does, but it is my understanding that an abrupt stall tendency is sometimes mitigated by washout. For those unfamiliar with the term, washout is the practice of building the wings with a deliberate slight spiral twist outward. As each rib is fastened to the spar, starting at the root end, there is a very slight twist as you progress outward, with the trailing end of the rib rises. Usually the washout is around 2", or so, and can be seen quite easily if you view the end of the wing, looking toward the fuselage. The stall characteristics of any airfoil are critical at a specific angle (regardless of the airfoil). By having "washout" the root of the wing may be, in fact, STALLED, while the outer portion of the wing is still flying, albeit barely!! Notice that when a wing is designed with built-in washout, that the tips of the wing are twisted UP, not down. The most apparent reason for this direction of twist, rather than twisting the wing down, is because as "stall" progresses outward along the wing, the last to stall is the outer portion....hence, still giving you aileron control. Although I haven't backed my statements up with documentation, as Rick so eloquently does, this is more of a "shade tree mechanic" understanding. Mike Welch Do Not Archive _________________________________________________________________ Helping your favorite cause is as easy as instant messaging.You IM, we give. ________________________________ Message 22 ____________________________________ Time: 06:52:55 PM PST US From: "Steven Green" Subject: Re: Kolb-List: The Kolb drop I have experienced Kolb quit, Cessna quit, and Piper quit. They all plop down if your wheels are not on the ground when they are through flying. Some call it "quit". I'll stick with "stall". Steven Mark III 912S 550 hrs. ________________________________ Message 23 ____________________________________ Time: 07:10:03 PM PST US From: "John Hauck" Subject: Re: Kolb-List: The Kolb drop Steven G: Been sitting here waiting for your eloquent response to a very simple question. Kolbs are simple little airplanes that are fun and easy to fly. If folks would spend more time playing with their Kolbs, rather than trying to tell others how to do it and why they do it, maybe they would learn how to land them without the dreaded "Kolb quit". I shared this new expression with Homer Kolb. Homer looked at me and gave me a big grin. john h mkIII - I have experienced Kolb quit, Cessna quit, and Piper quit. They all plop down if your wheels are not on the ground when they are through flying. Some call it "quit". I'll stick with "stall". Steven ________________________________ Message 24 ____________________________________ Time: 07:15:25 PM PST US From: Bob Noyer Subject: Re: Kolb-List: The Kolb drop It ain't The Drop, It's tha Sudden Stop. bn do not archive ________________________________ Message 25 ____________________________________ Time: 07:30:26 PM PST US From: "Richard Girard" Subject: Re: Kolb-List: Wings and their characteristics Mike, it's a good understanding, however you base it. The Hershey bar wing (untapered) like the Kolb's has this tendency naturally without twist. The other way you can get the same effect is to use aerodynamic twist and use a different or thicker version of the root airfoil. Rick On Feb 18, 2008 8:42 PM, Mike Welch wrote: > > > You'ze guys, > > I don't begin to have all the facts about airfoils like Rick does, but it > is my understanding that an abrupt stall tendency is sometimes mitigated by > washout. > > For those unfamiliar with the term, washout is the practice of building > the wings with a deliberate slight spiral twist outward. As each rib is > fastened to the spar, starting at the root end, there is a very slight twist > as you progress outward, with the trailing end of the rib rises. Usually > the washout is around 2", or so, and can be seen quite easily if you view > the end of the wing, looking toward the fuselage. > > The stall characteristics of any airfoil are critical at a specific angle > (regardless of the airfoil). By having "washout" the root of the wing may > be, in fact, STALLED, while the outer portion of the wing is still flying, > albeit barely!! > > Notice that when a wing is designed with built-in washout, that the tips > of the wing are twisted UP, not down. > The most apparent reason for this direction of twist, rather than twisting > the wing down, is because as "stall" > progresses outward along the wing, the last to stall is the outer > portion....hence, still giving you aileron control. > > Although I haven't backed my statements up with documentation, as Rick so > eloquently does, this is more of a "shade tree mechanic" understanding. > > Mike Welch > Do Not Archive > _________________________________________________________________ > Helping your favorite cause is as easy as instant messaging. You IM, we > give. > > ________________________________ Message 26 ____________________________________ Time: 08:32:16 PM PST US From: Ron Subject: Re: Kolb-List: Re: Test email I think they may be right to be concerned about the wrong material getting onto the wrong place. However Comet and the rest of them use silicates as in sand / abrasive and not the silicone that I use to lubricate hinges. One is an abrasive and the other is an artificial compound created by man. If I recall the story right silicone the lubricant is based on a secretion that some insects use to get away from predators, in other words its Slick. Why was it not named Slickon is a question to ponder about, Comet does not want slick they want none slick so they can scrub the surface. But I can see the confusion on the subject. I have used Comet and Ajax to clean alum pots and besides it working well it washed pretty well too. Ron (TxAz) ============================ ---- Richard Girard wrote: Everyone likes bonafides when a statement is a controversial statement is made. Here are mine. I was a bond and seal certified inspector at Boeing for many years. I sat through the required "Death by View Foil" classes every six months in order to maintain that cert. Boeing is absolutely anal about any forms of silicone contamination on the aircraft. It is used for sealing the windows into their frames as it can with stand the temperature extremes the airframes endure in their normal working environment. Absolutely strict quarantine is made of all materials, tools, and disposables used to work with silicone containing substances to prevent contamination of those surfaces that are painted or bonded. The reason is simple to understand, although I am not a chemist so I can only repeat what the engineers taught me. The problem is that silicone forms a molecular bond with anything with which it comes into contact. Once it contaminates a surface, you can sand it, blast it, chemically etch it, or burn it and the silicone simply works its way down to the next layer. I've discussed the use of car waxes containing silicones with car painters over the years based upon what I was taught at Boeing. To a man they hated them. Yes there are products that will encapsulate them so that repair work can be done, but you will never get the same bond you would if the surface was not contaminated. One engineer used this analogy: Imagine having a bunch of microscopic highly magnetic ball bearings spread out over a steel sheet. Now imagine how it would be to paint the sheet. Then imagine how well that coating of paint would hold up to a 400 mph wind blast at -50 degrees F. This silicone issue was particularly critical to the builders of composite aircraft like the LongEZ. Early on many builders found that peel ply was virtually the same as polyester dress sheathing (which is nearly the same as ultralight weight Polyfiber cloth for that matter) with one very important difference. The dress sheathing often has sizings applied to it which contains silicone. Builders would use the dress sheathing in place of peel ply and then find that bonding of subsequent layups was sub strength.Reallybad if say you're laying up the bonds that hold the winglets on a LongEz wing for instance. Anyone wishing to test the point can buy a can of dry silicone spray, make up two test panels one with silicone and one without. Spray a coat of good quality paint on both and do a peel test on each. This information is worth exactly what you paid for it, do with it as you wish. Rick do not archive trying to get better at remembering to include that. On Feb 17, 2008 10:14 AM, Ron wrote: > > That sounds odd to me Richard, why can't you get it off with say a sponge > with a good rinse of running water? > > Ron (AZ,TX) > > =========================== > > ---- Richard Girard wrote: > > ============ > Paint problems are caused by silicone. Once you get them on a surface, > they > can never be removed, only spread around. > > Rick > > On Feb 17, 2008 8:24 AM, russ kinne wrote: > > > > > In my experience , scratching the surface > > > > > > On Feb 17, 2008, at 6:41 AM, David Lucas wrote: > > > > > > > > What's the problem with having Silicates present in your cleaning > > > gear , Your Ajax's and Bon Ami's etc. ? Paint surface preparation > > > perhaps ? > > > > > > David. > > > > > > > > > > > > > > > Read this topic online here: > > > > > > http://forums.matronics.com/viewtopic.php?p=164535#164535 > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > kugelair.com > > -- kugelair.com ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message kolb-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Kolb-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/kolb-list Browse Digests http://www.matronics.com/digest/kolb-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.