From: krnet-bounces+markl=hiwaay.net@mylist.net on behalf of krnet-request@mylist.net Sent: Friday, November 21, 2003 12:00 PM To: krnet@mylist.net Subject: KRnet Digest, Vol 226, Issue 1 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. Re: type IV conversion manual dene colllet (Dene Collett (SA)) 2. Re: type IV conversion manual dene colllet (Mark Langford) 3. Lap belts (Colin) 4. Re: Lap belts (Barry Kruyssen) 5. Re: long hard summer is over (Dan Heath) 6. Re: Lap belts 7. Re: lap belt support (Rick Wilson) 8. Re: lap belt support (Ron Eason) 9. Re: lap belt support (Dan Heath) 10. RE: lap belt support (Dana Overall) 11. Re: lap belt support (Colin) ---------------------------------------------------------------------- Date: Thu, 20 Nov 2003 23:59:29 +0200 From: "Dene Collett \(SA\)" To: "KRnet" Subject: Re: KR>type IV conversion manual dene colllet Message-ID: <00d001c3afb1$afee2d40$37e5fea9@telkomsa127179> References: <000b01c3ac81$7e1d1660$a598ef9b@telkomsa127179><00dc01c3acaa$1cf6f3f0$1202a8c0@basement><00c601c3ad4a$770f9180$37e5fea9@telkomsa127179> <002501c3ae38$696b57f0$2402a8c0@800Athlon> Content-Type: text/plain; charset="iso-8859-1" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: list Message: 1 Mark L wrote > I talked to Steve Makish again last night, and he said he'd had one stocker> break and a Scat 4340 break.> Exactly why or how did they break? Was it failure of the taper due to gyroscopic forces? > I think if you'll ask around, you'll find more. If you want to talk strong> crank, check out the Corvair. > stock case, crank, and rods. I know y'all never imported Corvairs to SA, so > I understand why you wouldn't consider that option. Quite the contrary mark, we apparently did either import them or build them here (we did have a Chevrolet factory here in those days), the problem is, as far as I am aware, that only the early ones were sold here and not that many either. I know someone who found one at a local breakers yard.Believe me if I could find a "desirable" model corvair motor lying somewhere here I would'nt hesitate to defect purely for the extra power and smoothness reported. but I don't see the problem with > the stocker, assuming you use the "double thrust" bearings that almost > everybody uses (use the thrust half from two sets of bearings, so it > works from either direction. Now here is the reason why I belong to this group, I have never heard of the "double thrust system". Sounds very promising. Now you have really thrown a spanner in my works, I must learn more about this motor! > But the largest forces are gyroscopic (which are trying to bend the > crank repeatedly in opposite directions, leading to fatigue), not > torsional. You'll be testing for something that will probably not be > the primary mode of failure. Mark, respectfully I think you have missed what I plan on doing. I have designed a support structure that will house a double ball race, self aligning, sealed bearing situated just behind the prop hub that will handle just about all of the gyroscopic loads. All the crank will see is the torque loads and a very small amount of side load due to the relation between the length of the "drive shaft" ahead of the bearing compared to the length behind it.This side load probably wouldnt come near what a over tensioned belt would impose on the crank in a car.Here I am taking an educated guess so I welcome any information that will show me that my reconing is flawed. > You think a one in twenty risk of eventually having a forced landing > is acceptable? Absolutely not!What I am saying is that those one in twenty failures were probably due to fatigue caused by gyroscopic loads on that little taper at the end of the crank. If with my system I can eliminate the gyroscopic loads on the small taper of the crank I have no reason to believe that my system won't be as successful as the force 1 hub(provided the standard taper can handle the torque) I can't help but wonder why you wouldn't start with something proven, > like the GPASC Force One setup (although price would be a good guess). You are right on the money here, I am working on a shoestring budget and only have limited resources when it comes to machining. What I do have at my disposal at practically zero cost is a good friend who is one of the best tig welders I know of who just happens to be rated for aircraft welding. He also has a fairly good lathe and mill so most of my engineering work revolves around what we can do in-house at his shop. I searched the web for some shaft design stuff, and got bogged down > in everything but what I was looking for. Then it occured to me...the > reason I ditched the Type4 VW and went with the Corvair was because I didn't > want to have to design a drive shaft. Unfortunately I am stuck with the VW for now so I will just have to do the best I can with what I have at my disposal. > He echoed my sentiment to "go with the proven" GPASC Force One > system. I have no quarrel with this, remember , this hub is still on the pulley end and as long as it is kept as short as possible (I don't know how long a force 1 hub is) you shouldnt have any problems??? The reason I started all this redesign work was to have a substantially longer hub in order to achieve a really streamlined cowling. My friend's KR2 was a beautiful plane but I always thought it could do with a sharper more streamlined nose. It used a home made copy of the force 1 hub. I know of one aircraft engine company that paid an > engineering company to design a shaft drive system for them, and the > first example stuck on a customer's Type 4 self destructed in minutes! As I am NOT an engineer of any kind, my training is electrical and instrumentation, I won't even try to argue with you or anyone else more knowledgeable than I when it comes to things like tortional vibration, fatigue life, etc. The best I can do is compare my designs to things that have already been tried and use what was successful in the past, (or a combination of successful designs). To this end I will test a design using a significantly longer shaft than the force 1 hub attached to the crank using the existing taper ( subject to the taper performing well in the torque test ). To eliminate the mode of failure prone to the other hubs attached in this way in the past, I will be building the bearing housing support as mentioned above. I hope you'll decide to do something that's been proven already. > I know that sounds funny coming from me, but you've got to draw the > line somewhere. You are welcome to prove me wrong and crow about it, > but I'm not > going to encourage it... Mark I am not aiming at proving you or anybody else wrong and I certainly won't crow about it if by chance I do succeed, but it should be noted that I am literally miles away from having anything to attach this motor to in order to go flying behind it. My 2S is a long way from flying and I certainly won't stick a motor on the front of it that I was'nt reasonably sure will pull me around the skies as safely as I can make it possible. As William says "flying is risky", all we can do is keep that risk down to a minimum by not being irrisponsible by thinking we know it all no matter who we are or how many qualifications we have.( Please don't take that as a stab at you because it honestly isn't) I am a very humble person and don't feel threatened by someone who can teach me something. I value yours and everyone elses input regarding my idea and read each and every response to it.Since I started this thread, before I sit down in front of the PC I put on a second hand nomex flight suit and install a welding screen between myself and the monitor! I might try some sunblock as an added UV protection soon. I thank you for your help and patients up to now. I will post the results of my torque test as soon as it is done. Cheers guys dene.collett@telkomsa.net ------------------------------ Date: Thu, 20 Nov 2003 17:20:22 -0600 From: "Mark Langford" To: "KRnet" Subject: Re: KR>type IV conversion manual dene colllet Message-ID: <01f101c3afbc$e0e803c0$1202a8c0@basement> References: <000b01c3ac81$7e1d1660$a598ef9b@telkomsa127179><00dc01c3acaa$1cf6f3f0$1202a8c0@basement><00c601c3ad4a$770f9180$37e5fea9@telkomsa127179><002501c3ae38$696b57f0$2402a8c0@800Athlon> <00d001c3afb1$afee2d40$37e5fea9@telkomsa127179> Content-Type: text/plain; charset="iso-8859-1" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: list Message: 2 Dene Collett wrote: > Exactly why or how did they break? Was it > failure of the taper due to gyroscopic forces? I don't know HOW they broke, but I do know that one of them broke in the middle of a journal so it was basically captured, which kept the prop from flying off. Torsional vibration is my first guess, but I don't know. > Mark, respectfully I think you have missed what I plan on doing. I > have designed a support structure that will house a double ball race, > self aligning, sealed bearing... I realize that. It's the torsional vibration issue that worries me most. When you bolt anything onto the crank solidly, you change the dynamics of the system, and you're in uncharted territory. Of course, that didn't keep ME from bolting a pulley and a Nissan Sentra flexplate to my harmonic balancer hub, did it? So I guess I have no room to preach! > William says "flying is risky", all we can do is keep that risk down > to a minimum by not being irrisponsible by thinking we know it all no > matter who > we are > or how many qualifications we have.( Please don't take that as a stab > at you > because it honestly isn't) No problem there. I certainly don't claim to be any kind of super engineer. We all know our little niche well, but once out of there, we're just like everybody else, we have to do the research and come up to speed. Your first clue that somebody's blowing smoke is when they justify that they know what they're talking about because they're some kind of engineer! I know some mechanical engineers that don't have clue how an engine works, or how to get in out of the rain, for that matter. > You are right on the money here, I am working on a shoestring budget > and only have limited resources when it comes to machining. Understood, and if you have free machining and welding available, that's a big help. > Mark I am not aiming at proving you or anybody else wrong and I > certainly won't crow about it if by chance I do succeed, but it should > be noted that I > am literally miles away from having anything to attach this motor to > in order to go flying behind it. My 2S is a long way from flying and I > certainly won't stick a motor on the front of it that I was'nt > reasonably sure will pull me around the skies as safely as I can make > it possible. If you pull this off and it works great, you'll have every right to crow about it, and I hope you will! There are several ways to build an airplane. One is follow the tried and true and buy stuff that'll get you in the air soon, and the other is build and/or design as you go and don't worry about when it flies. Whatever works for you, and I wish you the best of luck with it. Please feel free to keep us informed on how it's going. You're right, that's why they call it experimental... Mark Langford, Huntsville, AL N56ML "at" hiwaay.net see KR2S project at http://home.hiwaay.net/~langford ------------------------------ Date: Thu, 20 Nov 2003 18:51:34 -0500 From: "Colin" To: Subject: KR>Lap belts Message-ID: <00c601c3afc1$3ac47b90$f2452141@Beverly> Content-Type: text/plain; charset="iso-8859-1" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: list Message: 3 Netters, I appreciate the responses thus far about my belts. I made the decision = not to mount the belts to the rear spar due to the reverse angle created = by the seats and such, as well as the weakening of the spars with more = bolts drilled and mounted. Although the previous builder had mounted the = lap belts (no shoulder belts were in yet), they had ridiculously small = brackets and AN3 bolts which I knew would be inadequate. Brackets around = the spar already cause sharp angles and opportunities for the belts to = get frayed and twisted, reducing their strength and life. I do not = desire a major structural failure by mounting the belts into the spar = with large appropriate bolts for strength, but reduce the integrity of = that spar.=20 My real questions are related to improving/strengthening the = existing mounts without the addition of too much weight, to allow the = belts to withstand a "normal" survivable crash. I do not wish to make = them, nor do I think I can make them withstand a major airframe = destruction crash, due to too many other variables. Like the KR2 that = crashed right after takeoff and the pilot walked away, but not before = exiting the aircraft through the BOTTOM of the aircraft, I think it is = nearly impossible to protect against every eventuality. Kind of like = adding seat belts to a motorcycle: it is a good thing in alot of the = cases of a crash, but not all of them. These belts are rated for the = automotive industry, so they are designed for what Scott Cable mentioned = in his reply. I desire to have them basically cause airframe damage to = the area they are mounted, because if I am receiving that much impact, = so is the plane, and I don't expect much of it to survive anyhow. Not = being a fatalist, just realistic about a major uncontrolled collision. Colin & Bev Rainey KR2(td) crainey1@cfl.rr.com http://kr-builder.org/Colin/index.html Sanford, Florida KR Gathering 2004-see ya in Mt VernonFrom jes@usfamily.net Thu Nov 20 15:58:04 2003 Received: from gv-m1.usfamily.net ([207.225.145.195]) by lizard.esosoft.net with smtp (Exim 3.36 #1) id 1AMygV-000GfW-00 for krnet@mylist.net; Thu, 20 Nov 2003 15:58:03 -0800 Received: from [205.158.33.162] by usfamily.net(USFamily MTA v2.0.1) with SMTP id com for ; Thu, 20 Nov 2003 18:02:21 -0600 (CST) (envelope-from jes@usfamily.net, authenticated user jes@usfamily.net) Message-ID: <001d01c3afc2$e05f6410$a2219ecd@CPQ28121814422> From: "j stevens" To: "krlist" Date: Thu, 20 Nov 2003 18:03:19 -0600 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1158 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1b3 Subject: KR>long hard summer is over X-BeenThere: krnet@mylist.net X-Mailman-Version: 2.1b3 Precedence: list Reply-To: KRnet List-Id: KRnet List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: List-Help: Well delay after delay I finally got my tailwheel endorsement today. I bought the kr in June and one system after another went down. The = major one being the elect igntion. Without the secondary ignition my = instructor would not fly in the kr. after starting with this instructer he plans to leave the country in a = few days. And instructers who will train in a kr are scarce around here = . I fixed the ig. prob., flew for two hrs got endorsed and=20 finished instalation if my brs all today whew!!! And to top it off my instructer could not get over how well iIwas able = to land in such a short time. I even stoped the bird in 1200 ft of runway! Needless to say Ill be rackin out the hours now. later Joel kr2s ------ http://USFamily.Net/info - Unlimited Internet - From $8.99/mo! ------ ------------------------------ Date: Fri, 21 Nov 2003 10:49:16 +1000 From: "Barry Kruyssen" To: "KRnet" Subject: Re: KR>Lap belts Message-ID: <01a601c3afc9$50e07340$ea00a8c0@t1w419> References: <00c601c3afc1$3ac47b90$f2452141@Beverly> Content-Type: text/plain; charset="iso-8859-1" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: list Message: 4 I agree that your lap belts are to far back. This can be very important. Let me explan by recounting an experiance I had. I'm flying a glider, an Open Cirus, turning my last turn point at 50kt with enough hight for a fast final glide to the gliding strip. I'm about to push the spead up so I tighten my belts. I push the speedup to cruising along at 90kts 5000ft in turbulant condition. I only have about 2in cleance on the canopy. It's quite rough so I pull hard on the harness ends and get the harness even tighter. Five minutes pass then I hit this "pot hole" that jams my head into the canopy and busts the canopy open, I'm daised by I manage to grab the canopy so I don't loose it (AU$2000 to to replace), gently pull the speed back to best glide, and try to clear my head. I do a gentle check of the controls and make a radio call to glide base stating my situation and ask a tug (tow aircaraft) to do a fly by. I'm wearing a chute so at this height I can getout, BUT Everything looks OK, I'm at 3000ft so I lower the undercariage and gently pull the airbrakes. Still all OK so I do a one handed landing (still holding the canopy). I'm told it was one of my better landings and all is OK. I'm left with a sore neck for several days. The lap hardness mount points were to far back and all they did was hold me back not down. I'm lucky I wasn't knocked out. The aircaft has since been fitted with a 5 point harness (one strap beween the legs). I'd ensure that the lap belts hold you down! Regards and safe flying Barry Kruyssen Cairns, Australia kr2@BigPond.com AUF Registered 19-3873 http://users.tpg.com.au/barryk/kr2.htm ----- Original Message ----- From: "Colin" To: Sent: Friday, November 21, 2003 9:51 AM Subject: KR>Lap belts Netters, I appreciate the responses thus far about my belts. I made the decision not to mount the belts to the rear spar due to the reverse angle created by the seats and such, as well as the weakening of the spars with more bolts drilled and mounted. Although the previous builder had mounted the lap belts (no shoulder belts were in yet), they had ridiculously small brackets and AN3 bolts which I knew would be inadequate. Brackets around the spar already cause sharp angles and opportunities for the belts to get frayed and twisted, reducing their strength and life. I do not desire a major structural failure by mounting the belts into the spar with large appropriate bolts for strength, but reduce the integrity of that spar. My real questions are related to improving/strengthening the existing mounts without the addition of too much weight, to allow the belts to withstand a "normal" survivable crash. I do not wish to make them, nor do I think I can make them withstand a major airframe destruction crash, due to too many other variables. Like the KR2 that crashed right after takeoff and the pilot walked away, but not before exiting the aircraft through the BOTTOM of the aircraft, I think it is nearly impossible to protect against every eventuality. Kind of like adding seat belts to a motorcycle: it is a good thing in alot of the cases of a crash, but not all of them. These belts are rated for the automotive industry, so they are designed for what Scott Cable mentioned in his reply. I desire to have them basically cause airframe damage to the area they are mounted, because if I am receiving that much impact, so is the plane, and I don't expect much of it to survive anyhow. Not being a fatalist, just realistic about a major uncontrolled collision. Colin & Bev Rainey KR2(td) crainey1@cfl.rr.com http://kr-builder.org/Colin/index.html Sanford, Florida KR Gathering 2004-see ya in Mt Vernon_______________________________________________ see KRnet list details at http://www.krnet.org/instructions.html ------------------------------ Date: Thu, 20 Nov 2003 20:03:56 -0500 (Eastern Standard Time) From: "Dan Heath" To: "krnet@mylist.net" Subject: Re: KR>long hard summer is over Message-ID: <3FBD647C.00001E.02292@Computer> References: <001d01c3afc2$e05f6410$a2219ecd@CPQ28121814422> Content-Type: Text/Plain; charset="iso-8859-1" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: list Message: 5 So much for a KR being hard to learn to fly. =0D =0D N64KR=0D =0D Daniel R. Heath - Columbia, SC=0D =0D DanRH@KR-Builder.org=0D =0D See you in Mt. Vernon - 2004 - KR Gathering=0D =0D See our KR at http://KR-Builder.org - Click on the pic=0D See our EAA Chapter 242 at http://EAA242.org=0D =20From phil@wotech.com.au Thu Nov 20 17:11:08 2003 Received: from dsl-202-72-188-202.wa.westnet.com.au ([202.72.188.202] helo=wotech.com.au)by lizard.esosoft.net with smtp (Exim 3.36 #1) id 1AMzpD-000JLx-00 for krnet@mylist.net; Thu, 20 Nov 2003 17:11:07 -0800 Received: (qmail 12597 invoked from network); 21 Nov 2003 01:16:36 -0000 Received: from unknown (HELO laptop) (192.168.1.3) by gangway.wotech.com.au (202.72.188.217) with ESMTP; 21 Nov 2003 01:16:36 -0000 From: "Philip Maley" To: "'KRnet'" Subject: RE: KR>type IV conversion manual dene colllet Date: Fri, 21 Nov 2003 09:16:29 +0800 Message-ID: <001001c3afcd$1ab3e6e0$0301a8c0@wotech.net> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.4024 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 In-Reply-To: <00d001c3afb1$afee2d40$37e5fea9@telkomsa127179> Importance: Normal X-BeenThere: krnet@mylist.net X-Mailman-Version: 2.1b3 Precedence: list Reply-To: KRnet List-Id: KRnet List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: List-Help: There is an article in this month's issue of the Australian SAAA journal "Sport Aviation" about Graham Schott's KR2 VH-XXS. This aircraft recently lost its propeller in flight and Graham and his wife Sue made a safe landing on a highway. It looks like the crankshaft had a fatigue failure near the prop hub. The article didn't give any engine details but according to the Australian register the engine is a C-85! There are some photos of XXS at http://home.hiwaay.net/~langford/gschott.html. Phil Maley Perth Australia ------------------------------ Date: Thu, 20 Nov 2003 21:16:55 EST From: FIXERJONES@aol.com To: krnet@mylist.net Subject: Re: KR>Lap belts Message-ID: <60.3835db3b.2ceecf97@aol.com> Content-Type: text/plain; charset="US-ASCII" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: list Message: 6 seatbelts are a must with sholder harness,,but no one so far has addressed roll over protection? the kr ( and alot of planes) have little if any support in the event of flipping over upside down. the canopy&turtle deck willnot support that kind of impact! i've installed a steel rollbar inside the turtledeck where the canopy meets. hopefully it will help to keep my head&back ok in the event of #@*%,,you know what i mean< yea it's extra weight & worth it,,steve jones,,N212KR ------------------------------ Date: Thu, 20 Nov 2003 18:20:18 -0800 (PST) From: Rick Wilson To: KRnet Subject: Re: KR>lap belt support Message-ID: <20031121022018.82501.qmail@web21206.mail.yahoo.com> In-Reply-To: <003901c3af1d$89b2e1a0$f2452141@Beverly> Content-Type: text/plain; charset=us-ascii MIME-Version: 1.0 Precedence: list Message: 7 Colin, I think I recall seeing somewhere that some builders chose to install cables from the rear of the aircraft (somewhere around the tailwheel attachment bolts) running forward to the shoulder belt attachment brackets. This was supposed to tie the brackets into the rear of the airframe. Just a suggestion, Rick Wilson. --- Colin wrote: > Netters, > I am looking for commentary critique of my mounting > of the lap belts in our KR. It is shown on our site > and Dan Heath expressed a valid concern about the > mounting. I would appreciate any commentary critique > of this mounting and potential improvements. Those > who have not gotten to this pint yet here is your > chance to learn before doing, to save you time. > > Colin & Bev Rainey KR2(td) > crainey1@cfl.rr.com > http://kr-builder.org/Colin/index.html > Sanford, Florida > KR Gathering 2004-see ya in Mt > Vernon_______________________________________________ > see KRnet list details at http://www.krnet.org/instructions.html ===== Rick Wilson, Haleyville, Alabama KR2-0200A -99% rwdw2002@yahoo.com __________________________________ Do you Yahoo!? Free Pop-Up Blocker - Get it now http://companion.yahoo.com/ ------------------------------ Date: Thu, 20 Nov 2003 20:51:47 -0600 From: "Ron Eason" To: "KRnet" Subject: Re: KR>lap belt support Message-ID: <00a901c3afda$68195d90$6501a8c0@Administration> References: <20031121022018.82501.qmail@web21206.mail.yahoo.com> Content-Type: text/plain; charset="iso-8859-1" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: list Message: 8 That's what I did with the center attachment [ 2 place]. I also brought dragster 5 way belts { 4" wide belts] with panic buckle from Jaggs speed shop. Ron ----- Original Message ----- From: "Rick Wilson" To: "KRnet" Sent: Thursday, November 20, 2003 8:20 PM Subject: Re: KR>lap belt support > Colin, I think I recall seeing somewhere that some > builders chose to install cables from the rear of the aircraft > (somewhere around the tailwheel attachment > bolts) running forward to the shoulder belt attachment brackets. This > was supposed to tie the brackets into the rear of the airframe. Just a > suggestion, Rick Wilson. > --- Colin wrote: > > Netters, > > I am looking for commentary critique of my mounting > > of the lap belts in our KR. It is shown on our site > > and Dan Heath expressed a valid concern about the > > mounting. I would appreciate any commentary critique > > of this mounting and potential improvements. Those > > who have not gotten to this pint yet here is your > > chance to learn before doing, to save you time. > > > > Colin & Bev Rainey KR2(td) > > crainey1@cfl.rr.com > > http://kr-builder.org/Colin/index.html > > Sanford, Florida > > KR Gathering 2004-see ya in Mt > > > Vernon_______________________________________________ > > see KRnet list details at > http://www.krnet.org/instructions.html > > > ===== > Rick Wilson, Haleyville, Alabama KR2-0200A -99% rwdw2002@yahoo.com > > > > __________________________________ > Do you Yahoo!? > Free Pop-Up Blocker - Get it now > http://companion.yahoo.com/ > > _______________________________________________ > see KRnet list details at http://www.krnet.org/instructions.html > ------------------------------ Date: Thu, 20 Nov 2003 21:56:40 -0500 (Eastern Standard Time) From: "Dan Heath" To: "krnet@mylist.net" Subject: Re: KR>lap belt support Message-ID: <3FBD7EE8.000030.02292@Computer> References: <20031121022018.82501.qmail@web21206.mail.yahoo.com> Content-Type: Text/Plain; charset="iso-8859-1" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: list Message: 9 That is what I did the first time, but this NET, convinced me that I did = not want to do that. If the tail gets caught up on something and rips off th= e plane, what happens to you? So, I did not do it that way this time.=0D =0D There was a long thread on that several years ago. =0D =0D N64KR=0D =0D Daniel R. Heath - Columbia, SC=0D =0D DanRH@KR-Builder.org=0D =0D See you in Mt. Vernon - 2004 - KR Gathering=0D =0D See our KR at http://KR-Builder.org - Click on the pic=0D See our EAA Chapter 242 at http://EAA242.org=0D =20From kr2cooper@earthlink.net Thu Nov 20 20:05:21 2003 Received: from firecrest.mail.pas.earthlink.net ([207.217.121.247]) by lizard.esosoft.net with esmtp (Exim 3.36 #1) id 1AN2Xp-000Kyl-00 for krnet@mylist.net; Thu, 20 Nov 2003 20:05:21 -0800 Received: from user-0c8hlqn.cable.mindspring.com ([24.136.215.87] helo=earthlink.net) by firecrest.mail.pas.earthlink.net with asmtp (Exim 3.33 #1) id 1AN2dB-0003wi-00 for krnet@mylist.net; Thu, 20 Nov 2003 20:10:53 -0800 Message-ID: <410-22003115213579520@earthlink.net> X-Priority: 3 X-Mailer: EarthLink MailBox 2004.0.129.0 (Windows) From: "Jack Cooper" To: "KRnet" Subject: RE: KR>lap belt support Date: Thu, 20 Nov 2003 22:57:09 -0500 MIME-Version: 1.0 Content-type: text/plain; charset=US-ASCII X-ELNK-Trace: 43a40ff3c21252eb71639b933de7ae6f7e972de0d01da94015f0a2674991029c4a2d9a1899f1aaef350badd9bab72f9c350badd9bab72f9c350badd9bab72f9c X-BeenThere: krnet@mylist.net X-Mailman-Version: 2.1b3 Precedence: list Reply-To: kr2cooper@earthlink.net, KRnet List-Id: KRnet List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: List-Help: Colin and other interested netters. I also have some concern about how your seat belts are mounted. Gene Byrd had his lap belts mounted to the rear spar cap strip with a AN 3 bolt, and the shoulder harness was attached to the tail with cables. He walked away from the crash with only minor scratched and some bruising. The bruises on his shoulders were from the shoulder harness. One side of the spar cap strip was broken where the seat belt mounting bolt split the spar and pulled out. Check the crash pictures an http://www.jackandsandycooper.com/byrdcrash.html I have not made my seatbelt attachments yet but they will be made of aluminum angle and attached to the rear spar through both the top and bottom strips with AN-3 bolts.. As you see in the pictures the KR tends to break apart at the spars so I have not decided how I will attach the shoulder harness. Its hard to say if Genes shoulder harness saved his life or did they only cause him injury (bruises) but if he had to ride through the same crash I bet he would say attach the harness to the tail just as it was. The bruises may have been a small price to pay. Robert J. (Jack) Cooper kr2cooper@earthlink.net http://www.jackandsandycooper.com/kr2.html Why Wait? Move to EarthLink. > [Original Message] > From: Colin > To: > Date: 11/19/03 11:19:55 PM > Subject: KR>lap belt support > > Netters, > I am looking for commentary critique of my mounting of the lap belts > in our KR. It is shown on our site and Dan Heath expressed a valid concern about the mounting. I would appreciate any commentary critique of this mounting and potential improvements. Those who have not gotten to this pint yet here is your chance to learn before doing, to save you time. > > Colin & Bev Rainey KR2(td) > crainey1@cfl.rr.com > http://kr-builder.org/Colin/index.html > Sanford, Florida > KR Gathering 2004-see ya in Mt Vernon_______________________________________________ > see KRnet list details at http://www.krnet.org/instructions.html ------------------------------ Date: Fri, 21 Nov 2003 06:59:48 -0500 From: "Dana Overall" To: krnet@mylist.net Subject: RE: KR>lap belt support Message-ID: Content-Type: text/plain; format=flowed MIME-Version: 1.0 Precedence: list Message: 10 Colin, Just as a point of reference, my current project's attachment points are as folllows: the seatbelts are attached to, what on a KR would be, the top and bottom spar caps of the rear spar using brackets to span the two structures. The crotch strap attachment point is forward enough to allow a couple inches between the crotch belt and the jewels. The shoulder harnesses attach to a cable which is bolted to the upper fuselage longerons. This attachment point is the position aft which allows a straight line to the attachment point of the shoulder harnesses themselves. Just thinking out loud here, if your shoulder harness cables are not run in a straight line intersecting at a midpoint between your shoulder blades, in a crash you will be pulled whatever direction opposite of any angle you have in the cable. Make sense?? Dana Overall 1999 & 2000 National KR Gathering host Richmond, KY RV-7 slider, Imron black, "Black Magic" Finish kit Buying Instruments. Hangar flying my Dynon. http://rvflying.tripod.com do not archive _________________________________________________________________ online games and music with a high-speed Internet connection! Prices start at less than $1 a day average. https://broadband.msn.com (Prices may vary by service area.) ------------------------------ Date: Fri, 21 Nov 2003 12:24:59 -0500 From: "Colin" To: "KRnet" Subject: Re: KR>lap belt support Message-ID: <00aa01c3b054$64298550$f2452141@Beverly> References: Content-Type: text/plain; charset="iso-8859-1" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: list Message: 11 Yes it does Dana, and they are straight back from individual belts to = their own brackets on a angle bracket attached to the longerons. Colin & Bev Rainey KR2(td) crainey1@cfl.rr.com http://kr-builder.org/Colin/index.html Sanford, Florida KR Gathering 2004-see ya in Mt VernonFrom kr2cooper@earthlink.net Fri Nov 21 10:29:03 2003 Received: from badboy.mail.pas.earthlink.net ([207.217.120.20]) by lizard.esosoft.net with esmtp (Exim 3.36 #1) id 1ANG1f-000CEy-00 for krnet@mylist.net; Fri, 21 Nov 2003 10:29:03 -0800 Received: from razorbill.mail.pas.earthlink.net (razorbill.mail.pas.earthlink.net [207.217.121.248]) by badboy.mail.pas.earthlink.net (8.11.7+Sun/8.11.6) with ESMTP id hALHmZE21920 for ; Fri, 21 Nov 2003 09:48:35 -0800 (PST) Received: from user-0c8hlqn.cable.mindspring.com ([24.136.215.87] helo=earthlink.net) by razorbill.mail.pas.earthlink.net with asmtp (Exim 3.33 #1) id 1ANFJJ-0006b3-00 for krnet@mylist.net; Fri, 21 Nov 2003 09:43:13 -0800 Message-ID: <410-2200311521172823780@earthlink.net> X-Priority: 3 X-Mailer: EarthLink MailBox 2004.0.129.0 (Windows) From: "Jack Cooper" To: "KR builders and pilots" Date: Fri, 21 Nov 2003 12:28:23 -0500 MIME-Version: 1.0 X-ELNK-Trace: 43a40ff3c21252eb71639b933de7ae6f7e972de0d01da940f35f2497844d221e82ab4b4edb42d70a350badd9bab72f9c350badd9bab72f9c350badd9bab72f9c Content-Type: text/plain; charset=US-ASCII X-Content-Filtered-By: Mailman/MimeDel 2.1b3 Subject: KR>seat belts X-BeenThere: krnet@mylist.net X-Mailman-Version: 2.1b3 Precedence: list Reply-To: kr2cooper@earthlink.net, KRnet List-Id: KRnet List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: List-Help: Has anyone installed a 5 point belt system where the stick is between the legs and a control tube under the seat.? (The aircraft control stick). I have a 5 point system but don't know how I' going to make it work. Robert J. (Jack) Cooper kr2cooper@earthlink.net http://www.jackandsandycooper.com/kr2.html Why Wait? Move to EarthLink.From s2cable1@yahoo.com Fri Nov 21 10:47:21 2003 Received: from web40808.mail.yahoo.com ([66.218.78.185]) by lizard.esosoft.net with smtp (Exim 3.36 #1) id 1ANGJN-000CQs-00 for krnet@mylist.net; Fri, 21 Nov 2003 10:47:21 -0800 Message-ID: <20031121185250.83903.qmail@web40808.mail.yahoo.com> Received: from [130.76.64.17] by web40808.mail.yahoo.com via HTTP; Fri, 21 Nov 2003 10:52:50 PST Date: Fri, 21 Nov 2003 10:52:50 -0800 (PST) From: Scott Cable Subject: Re: KR>lap belt support To: KRnet In-Reply-To: <00aa01c3b054$64298550$f2452141@Beverly> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-BeenThere: krnet@mylist.net X-Mailman-Version: 2.1b3 Precedence: list Reply-To: KRnet List-Id: KRnet List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: List-Help: Colin, While thinking of your Lap Belt Support, I thought of another more likely scenario where you could end up in serious difficulty with the method that you chose to attach your belts. You appear to be a fairly significantly sized individual, you probably weigh a little over 200 lbs? Ask any of the flying KR pilots what its like to hit turbulence in one of these little birds. Everyone of them will tell you it's not fun, maybe even downright scarey. With a lap belt attached through the rear spar, (yes, you should put doublers made out of plywood and or aluminum angle) you would be assured that the lap belt attachment stays put, therefore keeping you restrained when you encounter turbulence. If memory serves, isn't the KR designed to carry -4 G's? That means that attachment must be designed to carry at a minimum 1200 lbs ((200 x 4)x 1.5)=1200 lbs. This is the load per side i.e. pilot only. Lets say you're carrying a 150 lb passenger. Add another 900 lbs limit load to the same crossmember, skin and lower longeron, and you're up to 2100 lbs. That's at only -4 G's If you look at the 7 G case, you're looking at 2100 lbs on your side alone, 3675 combined limit load. The main problem that I see with the crossmember approach that you have made is that you place the lap belt fasteners in tension, not shear. The whole installation is a tension load. Generally speaking, if you load identical fasteners, one in shear, one in tension, the tension loaded fastener will fail at around 75% of the shear loaded fastener. Some people will want to argue about it, but ask any engineer, they will tell you that it's a much more effective joint in shear than in tension, which is why we always try to design our joints for shear. The strength department typically knocks down our fastener allowables by as much as 50% when the fastener is tension loaded. OK, so how would that equate to your installation? Double the limit combined load, that is what you have to design that structure for or 7350 lbs. The lower longerons and skin were never designed to carry that kind of point load. --- Colin wrote: > Yes it does Dana, and they are straight back from > individual belts to their own brackets on a angle > bracket attached to the longerons. > Colin & Bev Rainey KR2(td) > crainey1@cfl.rr.com ===== Scott Cable KR-2S # 735 Wright City, MO s2cable1@yahoo.com __________________________________ Do you Yahoo!? Free Pop-Up Blocker - Get it now http://companion.yahoo.com/ ------------------------------ _______________________________________________ See KRnet list details at http://www.krnet.org/instructions.html End of KRnet Digest, Vol 226, Issue 1 *************************************