From: KR-net users group digest[SMTP:kr-net@telelists.com] Sent: Wednesday, April 07, 1999 12:16 AM To: kr-net digest recipients Subject: kr-net digest: April 06, 1999 KR-net users group Digest for Tuesday, April 06, 1999. 1. Re Dragonfly canopy 2. Sun & Fun 3. Airfoils (long) 4. Re: Airfoils (long) 5. RAF airfoil 6. Re: Airfoils (long) 7. Re: Sun-n-Fun 8. Re: Canopies 9. Taildragger FLying 10. Got my KR-2S Plans today. Help!!! 11. Taildragger Endorsement! 12. Re: Got my KR-2S Plans today. Help!!! 13. Re: Taildragger Endorsement! 14. Great Idea! 15. another great idea! ---------------------------------------------------------------------- Subject: Re Dragonfly canopy From: John Bryhan Date: Tue, 06 Apr 1999 07:35:46 -0600 X-Message-Number: 1 Good choice - I used the dragon fly canopy it's flexible and pretty easy to mount. I went with the lite green. you? You guys expecting more snow down there? ---------------------------------------------------------------------- Subject: Sun & Fun From: KR2616TJ@aol.com Date: Tue, 6 Apr 1999 10:19:37 EDT X-Message-Number: 2 Anybody from the KRNet going to be around Sun & Fun on Friday and Saturday (the last weekend). Can't make it this year until after April 15. I'll be spending most of my time in the ground control tower or walking the booths, but if anyone is around and wants to be in on a couple of cookouts in the volunteer campground just outside the gate, let me know off the KRNet. Dana Overall 1999 KR Gathering host Richmond, KY mailto:kr2616tj@aol.com http://www.geocities.com/CapeCanaveral/Hangar/7085/ ---------------------------------------------------------------------- Subject: Airfoils (long) From: Steven Eberhart Date: Tue, 6 Apr 1999 11:05:47 -0500 (CDT) X-Message-Number: 3 THere has been a lot of traffic lately about airfoils. I waited to jump into the discussions until now but here goes. As Mark Langford has said numerous times, there was a project funded by contributions from KRNet members to have a family of new airfoils designed specifically for the KR-2 and KR-2S airplanes. THis project got its start right here on KRNet. Mark was the original catalyst when he announced that he was going to use the NLF(1)0115 laminar flow airfoil on his KR-2S. TO make a long story short, you can read the long version on Mark's web page, I too decided to use the NLF(1)0115 on my KR-2S. After reading the technical paper, authored by one of the designers of the airfoil Dr. Michael Selig, I started trying to size a wing for the KR-2S that was optimized for the weight and cruise speed I wanted. As it turned out, the NLF(1)0115 was designed for wings flying at higher Reynolds numbers than the small KR wing would see. Since I travel through Champaign, IL on a regular basis, I stopped in and talked to Dr. Selig about laminar flow wings in general and the NLF(1)0115 airfoil in particular on the KR-2S. Dr. Selig was concerned about the application and eventually agreed to wind tunnel test the NLF(1)0115 airfoil to document its characteristics at the Reynolds numbers a KR wing would operate within. The only problem was money. THe wind tunnel time was the least of the expense. THe wind tunnel wing would cost around $8,000 due to the tight tolerances that were required for a valid test. The wing, even though it was only 18" x 34" had to have a 1/16" carbon fiber skin and two 4130 steel spars that were machined to mate to the ballance that was used to measure forces within the wind tunnel. We eventually agreed to a project where I would make the wind tunnel wing and we would solicit contributions from KRNet to cover the cost of having a graduate student run the tests. Within less than a week we had received over $1,000 in donations from KRNet members, so the tests were a go. Ashok Gopalarathnan, a PhD graduate student studying under Dr. Selig was recruited to do the design work and run the wind tunnel tests. John Roffey, KRNet member, made the steel spars and I had the NLF(1)0115 wing almost complete when Dr. Selig offered Ashok's services in designing two completely new airfoils specifically for the KR (he actually ended up designing over eight new airfoils, the bes of which were the AS504x series). Seems that their research into the NLF(1)0115 resulted in the same concerns that I had about the Reynolds numbers. The first wing was scrapped and Ashok designed the new AS5045 15% and AS5048 18% airfoils. THe decision to design two airfoils, the 18% for the root and the 15% for the tip was based on Dr. Richard Mole's suggestions. THe thicker root airfoil would let a lighter spar to be used with a significant weight savings. A side benefit was the stalling characteristics of the 18% which would result in a softer stall starting at the root and progressing out to the tip. The original NLF(1)0115 wing was torn apart to salvage the spars that were going to be used in the 15% wing and John Roffey made up a second set of spars. After the new airfoils were designed we realized that it would be nice if we could have a single airfoil for those that wanted to use the existing stock KR spars. The AS5046 16% airfoil was then designed such that the stock spars could be used. It is this 16% airfoil that Troy Petteway is using on his KR-2. The airfoils were tested in the University of Illinois low speed wind tunnel last Summer and the wind tunnel results confirmed the computer predictions of the airfoils performance. Several analysis programs were used to evaluste the airfoils on the computer along with Mark Lougheed's CFD analysis and everything agreed with the wind tunmnel results. THe only remaing questions to be answered were how the airfoils actually would perform on a real airplane. Troy Petteway will be providing these answers when his plane flies, less than a month from now. A side bar is that Ashok worked as a summer intern for Bert Rutan's Scalled Composites last Summer. During his time at Scalled he designed the airfoils for Rutan's new Boomerang II. Pretty good cridentials if you ask me! For those of you considering alternate airfoils for your KR - be careful. Most, if not all, of the new laminar flow airfoils were designed for higher Reynolds numbers than our KR wings will be flying at. THis is not a recommendation for the AS504x series airfoils or any airfoil for that matter. It is just to provide a little history about one family of airfoils that are still going through the development phase. It is up to you the manufacturer of your airplane to make the engineering decisions about what modifications from plans stock you make. Just remember that there are no free lunches and there are always trade offs to be made. Get all of the facts before you make your decisions. Steve Eberhart ------------------------------------- http://www.newtech.com/nlf One test is worth a thousand expert opinions but a thousand opinions are easier to get. --plagiarized from an unknown author All information, in any of my aircraft related correspondence, is strictly food for thought and is in no way intended to imply that it is anything more than ideas requiring additional, qualified, engineering analysis. ---------------------------------------------------------------------- Subject: Re: Airfoils (long) From: "Mark Langford" Date: Tue, 6 Apr 1999 14:30:11 -0500 X-Message-Number: 4 Steve Eberhart wrote: >I started trying to size a wing for the KR-2S that was >optimized for the weight and cruise speed I wanted. As it turned out, the >NLF(1)0115 was designed for wings flying at higher Reynolds numbers than >the small KR wing would see. You're just not thinking far enough out of the box, bud. Who says MY KR won't go 230, especially now that I'm using the AS5046? Just kiddin', obviously... Very good report. It should be published in Kitplanes or Sport Aviation someday. But you left out the part about you slaving for several hundred hours to make three perfect airfoils for the wind tunnel with quality high enough to make a paint and body man cry... Mark Langford, Huntsville, Alabama mailto:langford@hiwaay.net see KR2S N56ML at http://home.hiwaay.net/~langford ---------------------------------------------------------------------- Subject: RAF airfoil From: Kimball Anderson Date: Tue, 06 Apr 1999 18:59:10 -0400 X-Message-Number: 5 Hello, everyone. If there is anyone out there who is building or has completed building their wings per the Rand Robinson plans, would you please contact me off the list? Full disclosure: This is an attempt to pick your brain and/or solicit written work about your wing-building experience -- with only the best intentions, of course. Thanks, Kimball Anderson isleno@hargray.com ---------------------------------------------------------------------- Subject: Re: Airfoils (long) From: KR2616TJ@aol.com Date: Tue, 6 Apr 1999 19:23:40 EDT X-Message-Number: 6 << As Mark Langford has said numerous times, there was a project funded by contributions from KRNet members to have a family of new airfoils designed specifically for the KR-2 and KR-2S airplanes. THe wind tunnel wing would cost around $8,000 due to the tight tolerances that were required for a valid test. We eventually agreed to a project where I would make the wind tunnel wing and we would solicit contributions from KRNet to cover the cost of having a graduate student run the tests. Within less than a week we had received over $1,000 in donations from KRNet members, so the tests were a go. After the new airfoils were designed we realized that it would be nice if we could have a single airfoil for those that wanted to use the existing stock KR spars. The AS5046 16% airfoil was then designed such that the stock spars could be used. It is this 16% airfoil that Troy Petteway is using on his KR-2. The airfoils were tested in the University of Illinois low speed wind tunnel last Summer and the wind tunnel results confirmed the computer predictions of the airfoils performance. Troy Petteway will be providing these answers when his plane flies, less than a month from now. Steve Eberhart >> Sorry, but I need to use the KRNet for a thank you. Thanks Steve. I asked Steve, in an earlier post if he could describe the process by which we raised money to finance a project especially for the KR. We are now over 400 strong, I remember when it was way less that a hundred. Thought some of the new people would like to hear the chronology of the wing development. Man, if I could get to Steve to make me a wing that looked as good as the wind tunnel test wing................work of art, Steve. For the times we have disagreements on the KRNet, look at what we can do. For those of you who haven't seen the online manual web page, Mark Langford has already posted, with pictures the forward deck section. Mike Mims has posted a written description of the rear deck. Others have already signed up for chapters. There will be no need to spend hours searching web pages for basic building techniques, it will all be on one page. I guess with that last statement, I need to duck away for the KRNet police. I'm innocent, I've been framed:-). I need a "good lawyer".........boy, that's a contradiction of terms.........only kidding. Dana Overall 1999 KR Gathering host Richmond, KY mailto:kr2616tj@aol.com http://www.geocities.com/CapeCanaveral/Hangar/7085/ ---------------------------------------------------------------------- Subject: Re: Sun-n-Fun From: Dennis Ambrose Date: Tue, 06 Apr 1999 22:25:14 -0400 X-Message-Number: 7 Hi: Just a short note to extend the offer I gave out last year at this time, but this year with a twist. I have a complete KR2 retract gear system, free to a good home, difference being I am going to sun'n fun in a car this year and if someone wants it I'll bring it with me. Prefer to give it to someone who has a genuine need for spare parts as opposed to someone looking for a really big piece of 7075 springbar to decorate their scrap bin!!! I know it makes a really substantial straight edge!! By the way, this one has the positive pin locking arrangement that I talked about last time. Let me know. Regards: Dennis (in Toronto) email:dambrose@accglobal.net ---------------------------------------------------------------------- Subject: Re: Canopies From: "Austin and Connie Clark" Date: Tue, 6 Apr 1999 20:30:56 -0500 X-Message-Number: 8 - >Has anyone purchased a Dragonfly canopy recently? What's the going price? >-Tom Tom, I orderd mine from Viking Aircraft in late November. The price at that time was $450.00 plus $15.00 crating. Shipping (to a business address in Mobile, AL) was around $60.00. They told me to allow 90 days, but I received it in mid January. Austin Clark KR2S 49% Complete Pascagoula MS www.datasync.com/~itac/ ---------------------------------------------------------------------- Subject: Taildragger FLying From: Ross Youngblood Date: Tue, 06 Apr 1999 21:24:19 -0700 X-Message-Number: 9 Well I had another TERRIFIC fun day in Idaho this evening flying the Aeronca Champ. I took a short hop from Nampa (S67) to Homedale (S66) and back. I have to say that I was apprehensive about getting my taildragger rating. The first several hours with instructors were once a week twice a week. This was really not going anywhere. Once I flew twice a day for three days in a row. Poof, I knew how to fly again. I had some squirrely three point landings the past couple of days, but in general, I feel much better about the prospect of flying my KR taildragger. I'm still planning on getting some Pitts or RV time, if possible before flying mine, but my anxiety level has dropped from a 6 or 7 to a zero on the issue. I'd recommend that if you can save up some $$ to fly three days in a row twice a day or at least once a day for a few days, it will be MUCH better than trying as I did to get taildragger time once or twice a week then stop and try again. I can't wait to finish my KR. The flight from CVO (Corvallis OR) to S67 (Nampa ID) would be quite a thrill in my own plane. As soon as I get home this week, I'm sanding ailerons and cowling. (Remaining stuff on my project). Again, anyone worried about flying the KR (like I was) just needs to spend a few days flying in a taildragger to get pumped up! -- Regards Ross ---------------------------------------------------------------------- Subject: Got my KR-2S Plans today. Help!!! From: "Rick Hubka" Date: Tue, 6 Apr 1999 22:21:45 -0600 X-Message-Number: 10 This is a multi-part message in MIME format. ------=_NextPart_000_0015_01BE807B.DAF9F6A0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hey Guys Got my KR-2S plans from RR today (Yippee!!) and finished the big work = bench. But ran out of money for wood for a few weeks. But I look at this a good thing. I need to read the plans over several = times and make some initial decisions. My preliminary thoughts are: 1) First I would like to make the seating area 4" wider. ( I'm 6.1 and = 220 lb. Lost 15 lb's over the winter. 30 more to go!) 2) Seriously evaluate and consider going with one of the new air foils. = This could change the spar dimensions. 3) Consider a laminated air frame like Dr. Dean. I have done a lot of = laminating. This changes everything! Just these 3 possibilities alone eliminate me buying a standard KR-2S = Spruce Kit. Although I know the local Calgary Spruce Kit supplier would modify my = order. I need to decide. I would appreciate some advice(I may not take it) from some of the = seasoned KRNet builders and I pose this question. If you could start over tomorrow (lets pretend you wanted to). How would you do the boat? Would you go with a new air foil? 15%, 16% with stock spars or ??? Rick Hubka Calgary, Alberta Canada ------=_NextPart_000_0015_01BE807B.DAF9F6A0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Hey Guys
 
Got my KR-2S plans from RR today (Yippee!!) = and finished=20 the big work bench.  But ran out of money for wood for a few=20 weeks.
 
But I look at this a good thing. I need to read the = plans over=20 several times and make some initial decisions.
 
My preliminary thoughts are:
1) First I would like to make the seating area = 4" wider.=20 ( I'm 6.1 and 220 lb.  Lost 15 lb's over the=20 winter.  30 more to go!)
2) Seriously evaluate and consider going = with one of=20 the new air foils.  This could change the spar=20 dimensions.
3) Consider a laminated air frame like Dr. = Dean.  I have=20 done a lot of laminating.  This changes everything!
 
Just these 3 possibilities alone eliminate me buying = a=20 standard KR-2S Spruce Kit.
 
Although I know the local Calgary Spruce Kit = supplier would=20 modify my order.  I need to decide.
 
I would appreciate some advice(I may not take it) = from some of=20 the seasoned KRNet builders and I pose this question.
 
If you could start over tomorrow (lets pretend = you wanted=20 to).
 
How would you do the boat?
Would you go with a new air foil? 15%, 16% with = stock spars or=20 ???
 
Rick Hubka
Calgary, Alberta   =20 Canada
------=_NextPart_000_0015_01BE807B.DAF9F6A0-- ---------------------------------------------------------------------- Subject: Taildragger Endorsement! From: Ross Youngblood Date: Wed, 31 Mar 1999 20:05:18 -0800 X-Message-Number: 11 Lets Celebrate! Your admin just completed his taildragger endorsement today! I have been working up in Nampa ID on business, so I decided to take advantage of the $34.00 hr rental rate on the Aeronca Champ. I did two wheel and two normal landings solo today! I'm excited about getting back to work on the KR! It turns out that my instructor works across the strip on the V12 Thunder Mustang. It's a bit bigger than a KR-2, and has 8 more cylinders, and two blades more on the prop, but it's still a taildragger, and it is retract. The downside is that the kit runs over $200K. I got a tour of the builder assist hangar today. There were two kits, and the second company prototype. (The first crashed some time last year). The prefab wing skins look similar to the KR pre-fab skins except they are black (carbon fiber). So consider the KR the first kit, then do the V12 Mustang next. Part of my flight training this week included touch and goes at a little airport where the runway was shared by some cattle. Makes me really want to own a taildragger! I was out at the hangar three weeks ago looking at my KR project and trying to figure out what to do next, when my boss paged me to go to Idaho for this trip. So I decided if I can't build it... at least I can get ready to fly it! Mike, I'm still working on being your wingman this year, but don't hold your breath! -- Regards Ross ---------------------------------------------------------------------- Subject: Re: Got my KR-2S Plans today. Help!!! From: Mike Mims Date: Tue, 06 Apr 1999 22:25:19 -0700 X-Message-Number: 12 > Rick Hubka wrote: > I pose this question. > > If you could start over tomorrow (lets pretend you wanted to). > > How would you do the boat? I don't know if I really want to answer this question but I will! I would build something else. -- zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz Micheal Mims KR290S (Sky Pig) ,..Building ailerons and sanding the wings.. mailto:mikemims@home.com http://www.geocities.com/CapeCanaveral/Hangar/4136/ Aliso Viejo Ca Friends don't let Friends fly behind Ivo Props! ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ---------------------------------------------------------------------- Subject: Re: Taildragger Endorsement! From: Mike Mims Date: Tue, 06 Apr 1999 22:28:00 -0700 X-Message-Number: 13 Ross Youngblood wrote: > > Mike, I'm still working on being your wingman this year, but don't hold your breath! > Don't worry I seriously doubt I will need one! :o) -- zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz Micheal Mims KR290S (Sky Pig) ,..Building ailerons and sanding the wings.. mailto:mikemims@home.com http://www.geocities.com/CapeCanaveral/Hangar/4136/ Aliso Viejo Ca Friends don't let Friends fly behind Ivo Props! ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ---------------------------------------------------------------------- Subject: Great Idea! From: Mike Mims Date: Tue, 06 Apr 1999 23:48:27 -0700 X-Message-Number: 14 http://members.aol.com/lee810/pump.html -- zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz Micheal Mims KR290S (Sky Pig) ,..Building ailerons and sanding the wings.. mailto:mikemims@home.com http://www.geocities.com/CapeCanaveral/Hangar/4136/ Aliso Viejo Ca Friends don't let Friends fly behind Ivo Props! ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ---------------------------------------------------------------------- Subject: another great idea! From: Mike Mims Date: Tue, 06 Apr 1999 23:53:53 -0700 X-Message-Number: 15 http://members.aol.com/Lee810/propfab.html -- zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz Micheal Mims KR290S (Sky Pig) ,..Building ailerons and sanding the wings.. mailto:mikemims@home.com http://www.geocities.com/CapeCanaveral/Hangar/4136/ Aliso Viejo Ca Friends don't let Friends fly behind Ivo Props! ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ --- END OF DIGEST --- You are currently subscribed to kr-net as: johnbou@timberline.com To unsubscribe send a blank email to leave-kr-net-17800J@telelists.com