From: krnet-bounces@mylist.net To: John Bouyea Subject: KRnet Digest, Vol 346, Issue 117 Date: 6/24/2004 9:00:06 PM Send KRnet mailing list submissions to krnet@mylist.net To subscribe or unsubscribe via the World Wide Web, visit http://mylist.net/listinfo/krnet or, via email, send a message with subject or body 'help' to krnet-request@mylist.net You can reach the person managing the list at krnet-owner@mylist.net When replying, please edit your Subject line so it is more specific than "Re: Contents of KRnet digest..." Today's Topics: 1. Widening the fuselage (larry flesner) 2. KR structural analysis (larry flesner) 3. Widening the fuselage (larry flesner) 4. Airventure (Brian Kraut) 5. Re: seat belts and spar strength (Phil Matheson) 6. gear attach brackets (Brian Kraut) 7. Re: Widening the fuselage (Donald Reid) 8. Re: lost messages? (Mark Langford) 9. Re: lost messages? (Jim Morehead) 10. Re: Barry Kruyssen - GRS ballistic chute (Barry Kruyssen) 11. - GRS ballistic chute (larry flesner) 12. getting current (larry flesner) 13. RE: High Alt (Doug Rupert) 14. Re: KR structural analysis (StRaNgEdAyS) 15. RE: seat belts and spar strength (dead horse alert!) (Ron Freiberger) ---------------------------------------------------------------------- Message: 1 Date: Thu, 24 Jun 2004 18:16:51 -0500 From: larry flesner Subject: KR> Widening the fuselage To: KRnet Message-ID: <3.0.6.32.20040624181651.0089e940@pop.midwest.net> Content-Type: text/plain; charset="us-ascii" There is no way that the stock KR firewall is >wide enough to look right with an O-200. >>Don Reid ++++++++++++++++++++++++++++++++++++++++++++++++++ Don, Are you calling my baby ugly?! :-) :-) http://home.hiwaay.net/~langford/flesner/relax.jpg http://home.hiwaay.net/~langford/flesner/taxi.jpg Larry Flesner ------------------------------ Message: 2 Date: Thu, 24 Jun 2004 18:20:54 -0500 From: larry flesner Subject: KR> KR structural analysis To: KRnet Message-ID: <3.0.6.32.20040624182054.0089e280@pop.midwest.net> Content-Type: text/plain; charset="us-ascii" >Bottom line, don't waste time looking for a structural analysis - it >doesn't exist, at least not from Rand Robinson and Jeanette isn't trained >to do one. >Larry Severson +++++++++++++++++++++++++++++++++++++++++++++++++++++++ I don't know about the structural analysis but I'm becoming quite versed on the "pucker factors". :-) Larry Flesner ------------------------------ Message: 3 Date: Thu, 24 Jun 2004 18:23:06 -0500 From: larry flesner Subject: KR> Widening the fuselage To: KRnet Message-ID: <3.0.6.32.20040624182306.0089ac40@pop.midwest.net> Content-Type: text/plain; charset="us-ascii" > > There is no way that the stock KR firewall is >>wide enough to look right with an O-200. >>>Don Reid >++++++++++++++++++++++++++++++++++++++++++++++++++ Don, Are you calling my baby ugly?! :-) :-) http://home.hiwaay.net/~langford/flesner/relax.jpg http://home.hiwaay.net/~langford/flesner/taxi.jpg Larry Flesner ------------------------------ Message: 4 Date: Thu, 24 Jun 2004 19:32:54 -0400 From: "Brian Kraut" Subject: KR> Airventure To: "KRnet" Message-ID: Content-Type: text/plain; charset="us-ascii" Copied from the RV list. Thought this might be of interest. A KR will fit right in the $10K spotlight. --> RV-List message posted by: "Ross Mickey" The EAA Homebuilt Council wants to showcase at AirVenture recently built experimentals that were built for $10,000, $20,000 and $30,000. If you know of anyone who has built an airplane that fits one of these categories who would like to be in the spotlight there and in a future issue of Sport Aviation, have them contact Wally Anderson at WALLYANDER@earthlink.net. Brian Kraut Engineering Alternatives, Inc. www.engalt.com ------------------------------ Message: 5 Date: Fri, 25 Jun 2004 09:41:25 +1000 From: "Phil Matheson" Subject: Re: KR> seat belts and spar strength To: "KRnet" Message-ID: <002201c45a44$c4388190$a096dccb@Office> Content-Type: text/plain; charset="iso-8859-1" Larry Like you I did not like the back rest belt area, so I used 10mm A/C ply for the shelf, on two 3/4"spruce cross members, then on the double longerons, where the 10mm ply is glued with T88. I put a 10mm ply webbing under those longerons which tied them all together I then placed 5/8"spruce from the rear spar to the parcel shelf, near the centre, and then two more from the rear centre of the shelf to the bottom, longerons, Why, because I will be using the shelf to sit on or lean on when getting in or out on the KR. And when I get the belts. I will use aluminium plate on either side of the self, or even glue another square of 10mm under the shelf for some extra thickness for the belt bolts.( or both). only to make me happy. Phil Matheson matheson@dodo.com.au VH-PKR ( Phil's KR) 61 3 58833588 Australia.( Down Under) See My KR2 Building Web Page at: http://mywebpage.netscape.com/flyingkrphil/VHPKR.html See our VW Engines and Home built web page at http://www.vw-engines.com/ www.homebuilt-aviation.com/ ------------------------------ Message: 6 Date: Thu, 24 Jun 2004 20:04:59 -0400 From: "Brian Kraut" Subject: KR> gear attach brackets To: "KRnet" Message-ID: Content-Type: text/plain; charset="us-ascii" I am going to have new Diehl like gear upper attach brackets made. They will be a little taller than the Diehl castings to fit the AS5048 spar better and they will be a hair narrower. The main reason I am doing this is to give me more ground clearance. I am changing the angle of the legs fom 50 degrees to 57.5 degrees which will give about another 1 3/4" ground clearance. They will be cut from 6061 aluminum plate with a HyDefinition CNC plasma cutting machine, have the holes drilled exactly the same on both brackets on my milling machine so they are reversible, have all corners radiused, be welded by a professional aircraft welder with more years of experience than I am old, then heat treated back to T6 by Braddock Metalurgical. If anyone else is interrested in a set please contact me offline at brian@engalt.com. They will be around $250 a set depending on how many I do. I am basically ofering them to cut down on the $175 minimum lot charge on the heat treating and the other one time costs. I am doing this one time and ordering metal Monday and will not make any more after that. I will also do a set of longer bottom brackets in 4130 in the next week or two done at the correct angle. Keep in mind that this will make the gear less springy, you will have to come up with your own glass, Scotchply, or aluminum legs, the bottom brackets are not included and I am not sure what they will cost yet, and I am not an aeronautical or structural engineer and make no warranties as to the suitibility of this to the KR or any other aircraft. I am just using them on mine and trying to cut the one time costs some. If anyone wants a drawing email me. Also, if anyone has any other 6061 aluminum to be heat treated and wants to share some of the minimum charge let me know. I will be doing some 4130 and some 1095 in the future also, but those minimums are only $60.00. Brian Kraut Engineering Alternatives, Inc. www.engalt.com ------------------------------ Message: 7 Date: Thu, 24 Jun 2004 20:08:02 -0400 From: Donald Reid Subject: Re: KR> Widening the fuselage To: KRnet Message-ID: <6.1.0.6.2.20040624200215.01c32e38@pop.erols.com> Content-Type: text/plain; charset="us-ascii"; format=flowed At 07:23 PM 6/24/2004, you wrote: > > > > There is no way that the stock KR firewall is > >>wide enough to look right with an O-200. > >>>Don Reid > >++++++++++++++++++++++++++++++++++++++++++++++++++ > >Don, > >Are you calling my baby ugly?! :-) :-) > >http://home.hiwaay.net/~langford/flesner/relax.jpg >http://home.hiwaay.net/~langford/flesner/taxi.jpg > >Larry Flesner No baby is truly ugly ... but a lot of babies do look just like Winston Churchill. Kidding aside, when you look at your plane's outline from the top, is the curve from the front of the cowling to the tail smooth and continuous? Mine would have been either discontinuous or would have required cheeks. One inch on each side made a huge difference. Don Reid - donreid "at" erols.com Bumpass, Va Visit my web sites at: AeroFoil, a 2-D Airfoil Design And Analysis Computer Program: http://www.eaa231.org/AeroFoil/index.htm KR2XL construction: http://users.erols.com/donreid/kr_page.htm Aviation Surplus: http://users.erols.com/donreid/Airparts.htm EAA Chapter 231: http://eaa231.org Ultralights: http://usua250.org VA EAA State Fly-in: http://vaeaa.org ------------------------------ Message: 8 Date: Thu, 24 Jun 2004 19:56:32 -0500 From: "Mark Langford" Subject: Re: KR> lost messages? To: "KRnet" Message-ID: <004301c45a4f$435840f0$1202a8c0@basement> Content-Type: text/plain; charset="iso-8859-1" I replied this morning that I have an average of 1 or 2 messages per week that go astray and never appear again, but that message never made it either! I'm going to start copying myself on them and the ones that don't make it I'll send to the powers that be at mylist.net and see if they can figure out what the deal is. There appears to be no pattern to it, and I've not noticed this with CorvAircraft, which also uses mylist.net. I flew the C-172 again today and apparently did quite well according to the instructorat least nobody died) so all I need to do now is some night flight and a little hood time and I'll have my BFR! I will remain "current" from here on out. The funny thing about the C-172 is that I crawled in it after 10 years and flew it perfectly, and it was so simple to fly! Why? Maybe 40 takeoffs and landings in a Champ and a Starduster did it. I'm also very close to getting my tailwheel endorsement. It's a good thing, because it won't be long before I'll need it! I'm still waiting on my Ellison carburetor, but have everything it takes to make a new manifold segment, so I'll do that over the weekend. I'm really getting fired up about this thing. I also ordered my seatbelts yesterday... Mark Langford, Huntsville, Alabama N56ML "at" hiwaay.net see KR2S project at http://home.hiwaay.net/~langford ------------------------------ Message: 9 Date: Thu, 24 Jun 2004 18:20:48 -0700 From: Jim Morehead Subject: Re: KR> lost messages? To: KRnet Message-ID: Content-Type: text/plain; charset="US-ASCII" Mark, Who did you order your seatbelts from? Jim Morehead Cameron Park, CA on 6/24/04 5:56 PM, Mark Langford at N56ML@hiwaay.net wrote: I also ordered my seatbelts yesterday... > > Mark Langford, Huntsville, Alabama > N56ML "at" hiwaay.net > see KR2S project at http://home.hiwaay.net/~langford > > > > > > _______________________________________ > to UNsubscribe from KRnet, send a message to KRnet-leave@mylist.net > please see other KRnet info at http://www.krnet.org/info.html ------------------------------ Message: 10 Date: Fri, 25 Jun 2004 11:16:11 +1000 From: "Barry Kruyssen" Subject: Re: KR> Barry Kruyssen - GRS ballistic chute To: "KRnet" Message-ID: <023701c45a52$0431fee0$4700a8c0@T1W419b> Content-Type: text/plain; charset="iso-8859-1" Several people have asked me about my ballistic chute so I added some photos and comments of where and why to my WEB page. (I'm slack when it comes to doing my WEB page) regards Barry Kruyssen Cairns, Australia RAA 19-3873 kr2@BigPond.com http://users.tpg.com.au/barryk/KR2.htm ------------------------------ Message: 11 Date: Thu, 24 Jun 2004 21:03:38 -0500 From: larry flesner Subject: KR> - GRS ballistic chute To: KRnet Message-ID: <3.0.6.32.20040624210338.0089fad0@pop.midwest.net> Content-Type: text/plain; charset="us-ascii" At 11:16 AM 6/25/04 +1000, you wrote: >Several people have asked me about my ballistic chute so I added some photos and comments of where and why to my WEB page. >(I'm slack when it comes to doing my WEB page) >Barry Kruyssen +++++++++++++++++++++++++++++++++++++++++++++++++++++++ Barry, I'm guessing that the bottom end of the cylinder for the chute that sticks out past the bottom of the fuselage will create a good deal of drag. You may want to fare in with some foam on the bottom side of the fuselage. The back side of the cylinder will be the highest drag area, not the front. Good luck on the first flight. Larry Flesner ------------------------------ Message: 12 Date: Thu, 24 Jun 2004 21:12:04 -0500 From: larry flesner Subject: KR> getting current To: KRnet Message-ID: <3.0.6.32.20040624211204.008a03e0@pop.midwest.net> Content-Type: text/plain; charset="us-ascii" I'm also very >close to getting my tailwheel endorsement. It's a good thing, because it >won't be long before I'll need it! >Mark Langford, Huntsville, Alabama ++++++++++++++++++++++++++++++++++++++++++++++++++++ After flying a tailwheel for several hours the nosedraggers are a piece of cake. I've managed to make two "perfect" three pointers in the last few hours in the KR. They weren't intentional but happened when I flared a foot or two too high and held it off when it started to settle. I guess that proves it can be done but I had little if any wind. The visibility over the nose is near zero at that point so a three pointer is not as comfortable as a smooth tail low wheel landing. With any crosswind I'll do wheel landings and then plant in on with forward stick. Let us know when the first flight gets close. Larry Flesner ------------------------------ Message: 13 Date: Thu, 24 Jun 2004 23:11:42 -0400 From: "Doug Rupert" Subject: RE: KR> High Alt To: "'KRnet'" Message-ID: <003901c45a62$35d6a210$a604e440@office> Content-Type: text/plain; charset="us-ascii" Larry I think a few of those U-2 pilots might tend to disagree. While they are not technically a glider, the wings were built long and lean for high altitude, long range work. Doug -----Original Message----- From: krnet-bounces@mylist.net [mailto:krnet-bounces@mylist.net] On Behalf Of larry severson Sent: Thursday, June 24, 2004 10:47 AM To: KRnet Subject: RE: KR> High Alt If you extend the wings, you also significantly reduce the allowable G loading. Gliders do not pull 6 G turns! Larry Severson Fountain Valley, CA 92708 (714) 968-9852 larry2@socal.rr.com ------------------------------ Message: 14 Date: Fri, 25 Jun 2004 13:15:11 +1000 From: "StRaNgEdAyS" Subject: Re: KR> KR structural analysis To: Message-ID: <40DB98BF.00001A.03976@motherfucker> Content-Type: Text/Plain; charset="iso-8859-1" Larry said: "The KR is a radio control model scaled up to one carrying people. It was not "engineered" at any time." I beg to differ, I was under the understanding that the KR was actually a scaled down version of a larger GA aircraft, right down to the RAF airfoil. (I think this info came from Mr Langford's site in the new airfoil blog) Cheers, Peter Bancks. strangedays@dodo.com.au http://www.homebuiltairplanes.com http://canardaviationforum.dmt.net ------------------------------ Message: 15 Date: Thu, 24 Jun 2004 22:18:17 -0500 From: "Ron Freiberger" Subject: RE: KR> seat belts and spar strength (dead horse alert!) To: "KRnet" Message-ID: Content-Type: text/plain; charset="us-ascii" We ran a cable to the vertical stabilizer point for a Jeanies' Teenee, and friend Art crashed it. The tail cone was damaged, and Art was pi___d about loosing his plane. Mark's right about the rear spar attach. Cable plan is good (IMHO). Ron Freiberger mailto: rfreiberger@swfla.rr.com -----Original Message----- From: krnet-bounces@mylist.net [mailto:krnet-bounces@mylist.net]On Behalf Of Mark Langford Sent: Wednesday, June 23, 2004 8:52 PM To: KRnet Subject: KR> seat belts and spar strength (dead horse alert!) NetHeads, There has been a lot of talk about seat belt brackets, bolt diameters, etc lately. I just ordered my seat belts today from Hooker Harness, and have been forced to think about attachment in order to come up with the proper belt lengths. The thing that concerns me most is the strength of the aft spar itself. If you think about laying the thing out flat between two sawhorses with a 32" space between them, I'll bet a lot of you would have second thoughts about merely STANDING on the middle of it, much less jumping up and down on it. I think the standard for seat belts is something like 20g's, so if you weigh 200 pounds, and have a 200 pound passenger with you (half of both would be 200 at the center), imagine 4000 pounds out there in the middle of that spar (laid flat). Do you think it would hold it? I'll bet you big money it won't. I stopped by my stress guy's office today, and talked him into working out the details for me (I'm more than just a little rusty). We assumed a 1" x 1" piece of spruce with 4000 pounds (pilot and passenger) of force out in the middle of that 32" span, neglecting the upper cap, and the vertical members and plywood connecting them to the "subject" lower cap (somewhat conservative). The number we calculated was 192,000 psi applied to that spar cap's spruce material in a 20g crash. The modulus of rupture in static bending is 9600 psi for aircraft grade spruce. So my apprehension of walking on that spar would be justified. Theoretically, 200 pounds would break that 1x1, and that passes my "common sense" test. Larry's idea of spanning the two caps with a bracket is a good one, since it calls both caps into play. Using that bracket to span the caps, and if you're the optimistic type and assume that the shoulder belt and lap belt will play equal parts bearing the load, and you have no passenger, then there's only 25 pounds (200/8) acting out in the middle of each cap, so the spar would handle something closer to an 8g crash. But I seriously doubt the shoulder belts do as much work as the lap belts do, so we're probably back to 6g's again, and that's with no passenger. My point is that although bolt diameter and bracket material are important factors, you also need to make sure the spar itself can handle it. Obviously the load of the seat belts needs to be shared with something other than the aft spar if you are preparing for a 20g crash. The two best ways I can think of are a compression member connecting the main spar to the aft spar (connected to both caps of each), or a cable connected to something like the tailwheel block. I know the cable thing will stir up the usual arguments, but I think that's exactly what I'm going to do...run cables from both center shoulder and center lap belt attachment points back to the something substantial in the tail (like the tailwheel block). I know we've all heard of KR's torn to pieces in a crash, and the guy walks away with the rear spar belted to his butt, but those are not the sort of full frontal crash that this 20g standard is based on. You say you're not going to worry about 20g frontal impacts because the chance of one is unlikely? I don't blame you. They are. But then why worry about bolt diameter or brace strength for a 20g crash if the spar's not going to take it anyway? And I'm not saying the cable strap is a 20g solution either, but that's what it'll take to make me comfortable, with minimal weight gain. Just thought I'd throw that out there. There are lots of ways to work this problem, and you're welcome to work it the way you want to. I need to get back to work if I'm going to fly to the Gathering. I just wanted to bring it up... Mark Langford, Huntsville, Alabama N56ML "at" hiwaay.net see KR2S project at http://home.hiwaay.net/~langford _______________________________________ to UNsubscribe from KRnet, send a message to KRnet-leave@mylist.net please see other KRnet info at http://www.krnet.org/info.html ------------------------------ _______________________________________________ See KRnet list details at http://www.krnet.org/instructions.html End of KRnet Digest, Vol 346, Issue 117 *************************************** ================================== ABC Amber Outlook Converter v4.20 Trial version ==================================