krnet-l-digest Wednesday, April 30 1997 Volume 01 : Number 005 ---------------------------------------------------------------------- Date: Tue, 29 Apr 1997 13:46:51 -0500 From: inet@intellisys.net (brian whatcott) Subject: Re: KR: Fire Sensors At 10:48 AM 4/29/97 -0700, krnet-l@teleport.com wrote: >> > >> If they don't cost too much they might be worth it >... I'm assuming an OPEN circuit would trigger the lamp. >Given the amount of vibration etc in the engine compartment, I expect >the likelyhood of a false alarm would be as high or higher than the >likely hood of an engine fire. This of course would depend on the >reliability of the sensors, the installation, and the number of sensors >installed. > > I think it's a good idea however, any warning is better than none. >But false alarms would be a real pain. Show me a simple installation >and I'll put them in my KR. > > - Ross Wire all thermal fuses in series. Suggest 1 amp thermal fuses in smallest practical size, mounted close to inlet manifold, motor mount, generator, vaccuum pump etc.... To a ground point - wire one end of fuse string. Connect other end of string to a cockpit accessible "push to test" switch (open when pushed) Connect other side of "push to test" switch to base of transistor. >From base of transistor, connect a 1200 ohm 1/4 watt resistor. Connect other end of resistor to 14 v battery power after master preferably through 1 amp breaker. Transistor is NPN like an MPS2222a ( to92 case secured with one screw) Connect emitter of transistor to ground Connect collector of transistor to 12 volt indicator lamp rated 1 to 4 watts. Connect other side of lamp to 14 volt battery power through the 1 amp breaker, like the resistor. Add item to preflight checklist: Master on, fire det cb on press fire det test button Lamp lights release button Lamp extinguishes. This is pretty simple, pretty light, pretty effective. Less important than a stall warning device, in my book, but still.... regards brian whatcott Altus OK ------------------------------ Date: Tue, 29 Apr 1997 14:19:16 -0500 From: inet@intellisys.net (brian whatcott) Subject: Re: KR: Fire Detector Fuses At 11:24 AM 4/29/97 -0700, krnet-l@teleport.com wrote: >>If I may respectfully suggest: ) Land - pronto. >> >>Sincerely >Only to find your 10 cent fire warning system has shorted and sent you a >false signal,. If the fuse string shorts - that's its normal state - no alarm. If one lamp wire shorts, or the transistor shorts, THAT'S a false alarm. Not very likely.... .> as you stand there scratching your head and looking at your >FIXED landing gear that is tucked neatly under your wing, you say "I know I >put the gear down!" so you wonder why your tire is sticking up through your >wing and how the heck are you going to get your airplane over too that >highway just over the horizon. > >Micheal Mims Didn't understand this comment - did you think we were talking about gear warning lights? Regards brian whatcott Altus OK ------------------------------ Date: Tue, 29 Apr 1997 14:08:03 -0700 From: Micheal Mims Subject: Re: KR: Fire Detector Fuses At 02:19 PM 4/29/97 -0500, you wrote: > as you stand there scratching your head and looking at your >>FIXED landing gear that is tucked neatly under your wing, you say "I know I >>put the gear down!" so you wonder why your tire is sticking up through your >>wing and how the heck are you going to get your airplane over too that >>highway just over the horizon. >> > >Didn't understand this comment - > did you think we were talking about gear warning lights? > No it was supposed to be a funny! You know.. forced, off airport landing causes fixed gear to break and fold up under the wing and poke up through the wing. The comment about the poor guy thinking he put his gear down on a FIXED gear airplane was just to show how confused this poor guy was during and after the forced landing. Micheal Mims ------------------------------ Date: Tue, 29 Apr 1997 16:30:26 -0700 From: daturley Subject: Re: KR: Fire Detector Fuses I flew King Airs for a while, and the photo-electric sensors would show a fire in the right engine every once in a while. (Especially after washing the engine or a good hard rain / windstorm)- the sunlight would glint off water droplets The checklist went: 1. Confirm normal engine gage indications (fuel flow, oil press) 2. Turn 45 degrees left or right 3. If #2 turns fire indication off, proceed back on course. 4. If #2 does not turn off the light, consider shutting down engine for a couple miles and then restart. 5. Under NO circumstances other than gage indications or visual fire identification will you push the fire bottle button, which will require an engine teardown and rebuild to clean the compressor of extinguisher powder!!! Are we thinking of a fire extinguishing system in the KR???? Also heated leading edge panels for icing protection and a King KFC 950 HF radio as well . . . . Sorry, just being a pill . . . Dave ------------------------------ Date: Mon, 28 Apr 1997 21:59:48 -0500 From: "Mark Langford" Subject: Re: KR: project update Bob Smith wrote: > About that type 4 -- I just recently gave up on the idea of type 4. Too many reports of crankshaft failures. > Seems there is a resonance problem that cant be overcome. I'm sure you are aware of the problem, so I'm > surprised you've recently decided to go that route. Well, we all know that I'm not too bright. But my plan at the moment is to build a prop shaft that runs off of the flywheel end of the engine, which would allow the use of the $550 welded stroker crank. The $1250 saved over the $1800 Scat crank would more than pay for the prop shaft stuff, and I'd have something that would allow lots of streamlining. It's pretty much designed, but I'm trying to decide if it's worth the time involved to prove it. And Steve's is due out soon, so I may wait to see how his looks before I take the plunge on my version. But there's something about running the prop off of the proper end (the one DESIGNED to take the thrust, although a thrust bearing will take that), and in the right direction, and very streamlined, that appeals to me... Of course, there's a weight penalty associated with it, and with the Type 4, but longevity is a factor as well. Still going with the Rabbit CIS injection too. Just call me stupid... Mark Langford langford@hiwaay.net http://fly.hiwaay.net/~langford ------------------------------ Date: Tue, 29 Apr 1997 20:21:01 -0500 From: "Mark Langford" Subject: Re: KR: Fuselage Widening Mike Mims wrote: > When I got my first ride in a KR2 (standard width) I had > to sit sideways and put my arm around the pilot! This is standard KR2 passenger behavior. Personally, I widened mine about 3 inches, which is perfect for me and my wife. And I widened it at the the shoulder for ergonomic and aerodynamic reasons, as Don Reid stated. Mark Langford langford@hiwaay.net http://fly.hiwaay.net/~langford ------------------------------ Date: Tue, 29 Apr 1997 21:53:22 -0700 From: "David M. Gargasz" Subject: Re: KR: project update Mark Langford wrote: > > Bob Smith wrote: > > > About that type 4 -- I just recently gave up on the idea of type 4. Too > many reports of crankshaft failures. > > Seems there is a resonance problem that cant be overcome. I'm sure you > are aware of the problem, so I'm > > surprised you've recently decided to go that route. > > Well, we all know that I'm not too bright. But my plan at the moment is to > build a prop shaft that runs off of the flywheel end of the engine, which > would allow the use of the $550 welded stroker crank. The $1250 saved over > the $1800 Scat crank would more than pay for the prop shaft stuff, and I'd > have something that would allow lots of streamlining. It's pretty much > designed, but I'm trying to decide if it's worth the time involved to prove > it. And Steve's is due out soon, so I may wait to see how his looks before > I take the plunge on my version. But there's something about running the > prop off of the proper end (the one DESIGNED to take the thrust, although a > thrust bearing will take that), and in the right direction, and very > streamlined, that appeals to me... Of course, there's a weight penalty > associated with it, and with the Type 4, but longevity is a factor as well. > Still going with the Rabbit CIS injection too. Just call me stupid... > > Mark Langford > langford@hiwaay.net > http://fly.hiwaay.net/~langford hi, Mark I cant remember where I read it about vw air conversions, but the author was against removing the stock flywheels on all vw enjines because they acted as a balancing damper to counter react the prop load. The fly wheel weighs about 20 lbs, might be the answer. Gene Gargasz % dave@erienet.net ------------------------------ Date: Tue, 29 Apr 1997 21:03:19 -0500 From: kencor@cneti.com (Ken Cornelius) Subject: Re: KR: Fuselage Widening >I have both sides of my fuselage built and am considering widening it by a >couple inches to have a little more shoulder room. Some say it needs to be >wider and others say the standard width is adequate. I am average build >and a wider cockpit may be more trouble than it's worth. I would be >interested in some comments from those who have "been there, done that" and >what they would do if they could do it over again. > >Thanks, > >Austin Clark > > Hi Austin, I'm of average build (5' 8" 160 #) and my son is taller but weighs about 15# less than me. I widened my KR 3" and we both fit comfortablely in it. Ken Thomas widened his 4" but he weighs about 240#. He sayes his is OK with him and a smaller pasenger. I had no problems widening mine. Hope this helps. Ken Cornelius ------------------------------ Date: Tue, 29 Apr 1997 20:18:45 From: Austin Clark Subject: Re: KR: Fuselage Widening At 09:20 4/29/97 -0700, you wrote: >Austin Clark wrote: >> >> I have both sides of my fuselage built and am considering widening it by a >> couple inches to have a little more shoulder room. Some say it needs to be >> wider and others say the standard width is adequate. I am average build >> and a wider cockpit may be more trouble than it's worth. I would be >> interested in some comments from those who have "been there, done that" and >> what they would do if they could do it over again. >> >> Thanks, >> >> Austin ClarkI added three inches to the width of a -2S but I am a very large guy at >6' 9" and 235#. If I were to do it again, I would have added 5 instead. >If you are going to use to prefab pieces, you are limited in what will >fit. With scratch built, you can do almost anything. A Dragonfly canopy > fits perfectly on the wider fuselage. > >If I were to do mine over, I would make the widest point of the fuselage >at the shoulders, not at the main spar. The extra room would be nice and >the wing/fuselage interference drag would be less. Again, this depends >on what you are willing to build vs. buy. > >Don Reid > I think you are on the mark with the 5 inches. I am 20 inches wide at the shoulders so I figure I need at least 40 inches at shoulder height. I did a quick drawing on my CADD and added 5 inches at "D" (43 inches instead of 38) and "G" (41.75 instead of 36.75) and left the "A" dimension at 36 inches. A bezier curve from the tail post to approximatley the front of the cowling intersecting these points produces a nice streamlined curve. This will give me about 41 inches inside at the widest point. I am building from scratch so the changes are no problem for me. I think I can leave the fuselage bottom width dimensions to plans. I will jig it to the table this weekend and see how it looks. Thanks, Austin Clark ------------------------------ Date: Tue, 29 Apr 1997 19:44:42 From: Austin Clark Subject: Re: KR: Fuselage Skin At 18:56 4/28/97 -0700, you wrote: >At 07:05 PM 4/28/97, you wrote: >>I've noticed some of the KR web pages show photos of the fuselage frame >assembled without the plywood skin. > >I did not encounter any problems, I used staples and clamps to hold my skin >in place until it cured. I assembled my sides as per plans without the >skin and then installed the belly skin first before I removed it from the >jig. After the belly skin cured I flipped it over and installed the side >skins. Piece of cake! > >Micheal Mims Michael, Did you make your scarf joints in the plywood before installation or during installation? I am considering making the scarf joints and letting them cure before installing the skin. Austin Clark ------------------------------ Date: Tue, 29 Apr 1997 20:35:36 From: Austin Clark Subject: Re: KR: Wood Repair (not a keeper for Archives) At 21:57 4/28/97 -0400, you wrote: >In a message dated 97-04-25 03:27:54 EDT, you write: > ><< > like Jim mentioned, I would feel comfortable with injecting epoxy into >the > > crack. > > > > Austin Clark > > I think the injecting epoxy idea is a sound one too. I'm not too sure > about super glue, as it doesn't fill gaps as good as epoxy, but given > a fresh break, clamping should fill all the gaps. Modern adhesives > are wonderful. > > -- Ross >> > > I forgot to mention that the superglue was of the thicker variety and >the FAA inspector did have me run some breakage tests which all broke the way >we want (in the wood). The stuff did squeeze out of the cracks after >allowing the wood to return to its natural form. I hadn't heard of the >longevity aspect tho. Anyone have any suggestions as to what else I should >do? I mean should I additionally epoxy a doubler or something like that >along that area? He didn't mention anything about any longevity problems and >I surely thought he knew what he was talking about. > >Jim Hayward > > Jim, I injected epoxy into a split in a longeron by wedging a very small screwdriver into the split and moved it back and forth to work the epoxy down into the wood. I clamped it and let it cure. I have more faith in this repair than a scarfed joint. However, I oriented the longeron so that the plywood skin will act as a doubler over the repaired area. I think I would put a doubler over any repaired area if possible even if the only benefit is piece of mind. Austin Clark ------------------------------ Date: Tue, 29 Apr 1997 23:55:16 -0400 (EDT) From: DAmbrose12@aol.com Subject: Re: KR: Fire Detector Fuses These thermal fuses don't false alarm. If you read the article, it said that the fire indication light should be taken as a POSSIBLE fire indication. Now we wouldn't want to see a plane crash while staring at a red light( like the plane that flew into a mountain while the crew fussed over a cockpit light!) These thermal fuses are available in temp. ratings from about 160F and up. The size in your kettle is probably in the 180 degrees celcius range. (Sorry about mixing temp. units) In Toronto they can be purchased for $1.35 each at a local surplus electronics shop. Once they open they are garbage so you have to replace them. I wouldn't put them near the exhaust, manifolds will get VERY hot as the exhaust temps are high. As for their value?? If there is a small fire under the hood, I'd like the chance to deal with it as soon as possible! ie. If it's fuel related, shut off supply. If it's electrical shut off the master-- you know the drill. At 150 M.P.H. you may not see smoke until it's a MAJOR fire. I think i'll build the circuit. Regards Dennis. ------------------------------ Date: Wed, 30 Apr 1997 00:53:18 -0400 (EDT) From: MikeTnyc@aol.com Subject: KR: Using AC Switches with DC I didn't save the post about how electrical switches designed for AC have less capacity with DC, but today I found a microswitch kicking around on my desk with capacities listed for both, and I was shocked to discover how MUCH less capacity they have for DC. This particular switch (Micro micro switch, Freeport Ill, #V3-1171-D8) has a listed capacity of 10 amps at 125 or 250 VAC, but only 1/4 amp at 250 VDC. Is this 40-fold decrease typical of all switches, or just of this type of microswitch? Mike Taglieri ------------------------------ Date: Wed, 30 Apr 1997 00:53:21 -0400 (EDT) From: MikeTnyc@aol.com Subject: Re: KR: Fuselage: Covering with 1.45 oz deck cloth In a message dated 97-04-23 01:09:43 EDT, you write: >> Maybe I'm missing something, but if you are covering with glass I would >> >assume it is for structural purposes. If not, why even bother. >> >> Yep your missing something! As we all know the KR doesn't need any >> strength added! The layer of glass is too aid in sealing the plywood, so >> don't overlap the dang joints! YOU don't have to use the layer of glass if >> you don't want too, but it is recommended by 9 out of 10 who have built a >> KR, of course there are some people who insist on not listening to people >> who have been there! :-) > >I haven't met these other 9 folks. The first KR I saw looked terrific, and >when >I asked the owner what he did to seal the plywood, he indicated he just used >primer >and paint. I think he did seal the staple holes with filler however, thats >when I >decided that I didn't need to do anything to the plane. I guess I need to go >to >a KR gathering and meet the 9 other guys. ;) To some extent, it depends on where you plan to store the plane, doesn't it? Around here, I would never be able to afford a hangar, and the climate can be pretty damp, with lots of rain and some snow in the winter. If a wood plane is practical at all under such circumstances (and I think it is, with good varnishing) I would want the fuselage to be watertight even if it got a nick from a stone, etc, on the paint. To me, this would suggest deck cloth AND a slight overlap. Guys in So. Cal. and Arizona may think differently. If anybody thinks a person without a hangar shouldn't build a wooden plane, I'd be interested in hearing that discussion, also. Mike Taglieri ------------------------------ Date: Wed, 30 Apr 1997 00:53:24 -0400 (EDT) From: MikeTnyc@aol.com Subject: Re: KR: KR Wing Ribs In a message dated 97-04-24 08:50:57 EDT, you write: >>> Structural? Well in a way, they are. If you have ever flown in a KR you >>> will notice the top wing skin bows up quite a bit at higher speeds. The >>> fiberglass skin attached to the spars and the underside of the foam >>> connected to the ribs keeps this from getting out of control. >>I am curious about the wing bowing line that has been talked about. > > I have never noticed my wing bowing even in a 200 mph pass. This may be >because of the extra layer of 4 oz glass I used over the entire wing or it >may not. Do any of the other flying KR's wings bow - or - am I just >>too happy in the KR to really notice that mine are bowed? >> >>Jim Faughn >>N891JF >> >I have never seen any bow in my wings, but I'm not even sure of what a bow >is. At over 200mph dives, the wings look the same as they do at 70mph. Also >they look the same at 12,000 feet as they do on the ground. Sometimes based >upon the sunlight, the wings show the spar line but that is a >construction/finishing issue. > >Bobby Muse >bmuse@mindspring.com Bobby, did you also use extra layers of glass or build them "normal?" There seem to be as many different building techniques on this list as there are people. Mike Taglieri ------------------------------ Date: Wed, 30 Apr 1997 01:01:36 -0700 From: Owen Davies Subject: Re: KR: Fuselage Widening Does anyone have a good grip on how much difference a wider fuselage makes to your cruise and top end? Many thanks. Owen Davies ------------------------------ Date: Tue, 29 Apr 1997 23:05:01 -0700 From: Micheal Mims Subject: Re: KR: Fuselage Skin At 07:44 PM 4/29/97, you wrote: Michael, > >Did you make your scarf joints in the plywood before installation or during >installation? I am considering making the scarf joints and letting them >cure before installing the skin. > I cut out the pieces and made all the scarf joints but I applied one skin at a time. I think I installed the forward section first, after it cured I then installed the aft skin. The reason I waited to install the second skin was to make sure I would have a good solid surface to apply pressure too around the scarf area. Bonding the skins before applying them may be the easier way to go although I had no problems. Micheal Mims ------------------------------ Date: Tue, 29 Apr 1997 23:10:33 -0700 From: Micheal Mims Subject: Re: KR: Fuselage Widening At 01:01 AM 4/30/97 -0700, you wrote: >Does anyone have a good grip on how much difference a wider >fuselage makes to your cruise and top end? > >Many thanks. > We talked about this a few months back, I personally don't think its gona have any effect at all, Is an RV6 slower than a RV4 with the same HP? Is the KR2 just as fast or faster than a KR1 with the same HP? I guess we will just have to wait and see. Micheal Mims ------------------------------ Date: Wed, 30 Apr 1997 02:50:59 -0500 From: Bobby Muse Subject: Re: KR: ? on Trim Tabs At 01:46 PM 4/25/97 -0400, you wrote: >> That's all, and If I just caused any confusion with my inexperienced >> way of explaining things, let me know and I'll find a better way of >> explaining it. I hope! > >Oops! >Would >> these serve a purpose on a KR? I doubt anyone is snap rolling the heck >> out of these things(KR's), or doing inverted flat spins! YEA! > > I forgot... If anyone would like a diagram, I'm sure I could work >something up in a dwg of bmp format. > > >-- >Vince Bozik - Athens, Georgia I don't do flat spins!. Bobby Muse ------------------------------ Date: Wed, 30 Apr 1997 02:51:01 -0500 From: Bobby Muse Subject: Re: KR: wing flaps and ailerons At 07:04 PM 4/25/97 -0800, you wrote: My opinion is that if the pitching rate and the the roll >rates could be swapped things would be just right. Don't get me wrong >I enjoy the KR-2 very much but for my liking I would increase the roll >rate slightly and decrease the pitching rate of the associated >controls. > >Regards >Parley Byington > > I can't disagree with you at all... Bobby Muse ------------------------------ Date: Wed, 30 Apr 1997 02:51:02 -0500 From: Bobby Muse Subject: Re: KR: Possible builder...(NOT FOR ARCHIVE) At 09:49 AM 4/27/97 -0400, you wrote: >On Fri, 25 Apr 1997, Steven A Eberhart wrote: >> On Wed, 23 Apr 1997, Tom Crawford wrote: >> [big editorial snip] >> > This is not counting about the same >> > number of hours standing there with a dumb look on my face, scratching my >> > head trying to figure out how to do something that is not made clear in the >> > construction manual. >> Construction manual? Construction Manual? you got a construction manual? >> I got a notebook that meticulously described how to make the retractable >> gear that nobody is using, some notes on construction methods and some >> notes and drawings. After you take out the retract section and the >> construction methods sections there is very little left filling up the >> book. Compare that with what you get for a Cozy IV and it makes you >> wonder. Oh well, as I have said >> before, I am keeping the design for the drink holder and scrapping most >> everything else - guess I didn't need a manual after all ;-) >> >> Steve Eberhart > >Steve, >You are right about the manual. When I first saw it before I began building, >I thought Geez- if that's all there is to it, I should have this sucker done >in about six months. HA! Take a look at a Lancair or Glassair manual. At >least with them you know what you are in for. > > >Tom Crawford KR4QV >Gainesville, FL > Well all things are not perfect. One of the things that is great about building is that the plans and design give you the ability to creative and unique. Bobby Muse ------------------------------ Date: Wed, 30 Apr 1997 02:51:04 -0500 From: Bobby Muse Subject: Re: KR: aileron linkage At 05:26 PM 4/28/97 -0700, you wrote: >At 08:18 PM 4/27/97 -0700, you wrote: >>Robert Lasecki wrote: >>> >>> Can anyone advise me regarding the proper angle for aileron belcrank >angle with respect to the main spar at zero deflection? The "construction >manual" is slightly vague :-( > Also, am I correct is seeing that 3/16 hardware is shown for use with the > aileron pushrods yet the pushrod bearings are bored out for 1/4" screws? > > In regards to the 3/16 or 1/4 inch bolts or >hardware, I am assuming your tie rod ends have a .250 bore instead of a .1900 bore. In that case I would either drill the bellcrank and aileron bracket to 1/4 inch or send the tie rod ends back for the ones with the correct bore. > >On the angle thing Im still lost! If you are talking about setting the aileron in the neutral position and rigging your cables, then the belcrank should be 90 degrees or parallel depending on which arm you are aligning with the aft face of the spar (see below), otherwise you lost me! > > : <- cable to stick > : > : >______:_______________ <- spar > / | ---:-------------------------- <- cable to other belcrank > / |__: <--belcrank > / > / <- pushrod > >Micheal Mims >mailto:mimsmand@ix.netcom.com >http://www.netcom.com/~mimsmand Recommendation: Drill a locking pin hole through eack of the belcranks and mounting brackets so that they can be locked into the proper angle/position. Once locked, all of the aileron cables and push rods can be proper lenghtened and adjusted.Bobby Muse bmuse@mindspring.com ------------------------------ Date: Wed, 30 Apr 1997 03:14:54 -0500 From: Bobby Muse Subject: Re: KR: Fuselage Widening At 06:50 PM 4/28/97, you wrote: >I have both sides of my fuselage built and am considering widening it by a >couple inches to have a little more shoulder room. Some say it needs to be >wider and others say the standard width is adequate. I am average build >and a wider cockpit may be more trouble than it's worth. I would be >interested in some comments from those who have "been there, done that" and >what they would do if they could do it over again. > >Thanks, > >Austin Clark > I weigh 200lbs, 5'9" and I find the standard width to be adequate. N122B is built to plans as far as the dimensions are concerned. But being a little wider would be nice. But would I make it wider if I could do it over again....NO! By the way....It would be nice to be wider, longer, faster, less expensive, not needed to be white, aerobic, not required to be hanagered, etc....but I love flying my KR just the way it is.Bobby Muse bmuse@mindspring.com ------------------------------ Date: Wed, 30 Apr 1997 04:09:13 -0500 From: Bobby Muse Subject: Re: KR: aileron linkage At 03:12 PM 4/29/97 +0000, you wrote: Did you mount your rudder pedals on the floor or from the >shelf? The "new" plans Jeanette has show the rudder cables routed along the >fuselage sides. Using the nylon blocks or other techniques, isn't there a >lot of friction when the cables are tensioned? Also, the "construction >manual" (using the term very loosely) refers indirectly to adding return >springs to the rudder cables to keep the cables tensioned. Any suggestions >before I try to re-invent the wheel?> > FYI, (1) It doesn't matter if the rudder pedals are mounted on he floor or the shelf. Mine is mounted on the shelf but the master cyclinders would be easier to install if the pedals wre mounted on the floor. (2) The rudder cables are guided by nylon or phenolic(sp) blocks and used plenolic blocks. The friction is not noticeable. But I would like to suggest that you consider using Nynaflow tubing to route your cables thru as used in the Lancair. With the Nynaflow tubing you can make major changes in the direction of the cable with very little friction. If I would do it over I would use Nynaflow, but the phenolic works good. (3) A major reason for the return springs is to keep the rudder pedals in the proper position when you take your feet off of the pedals. I used a single spring connected between cables coming from the front of each rudder pedal, thru pulleys mounted at the inside outboard corners of the firewall. Bobby Muse bmuse@mindspring.com ------------------------------ Date: Wed, 30 Apr 1997 04:41:54 -0500 From: Bobby Muse Subject: Re: KR: KR Wing Ribs At 12:53 AM 4/30/97 -0400, you wrote: >In a message dated 97-04-24 08:50:57 EDT, you write: > >>>> Structural? Well in a way, they are. If you have ever flown in a KR you >>>> will notice the top wing skin bows up quite a bit at higher speeds. The >>>> fiberglass skin attached to the spars and the underside of the foam >>>> connected to the ribs keeps this from getting out of control. >>>I am curious about the wing bowing line that has been talked about. >> >> I have never noticed my wing bowing even in a 200 mph pass. This may be >>because of the extra layer of 4 oz glass I used over the entire wing or it >>may not. Do any of the other flying KR's wings bow - or - am I just >>>too happy in the KR to really notice that mine are bowed? >>> >>>Jim Faughn >>>N891JF >>> >>I have never seen any bow in my wings, but I'm not even sure of what a bow >>is. At over 200mph dives, the wings look the same as they do at 70mph. > Also >>they look the same at 12,000 feet as they do on the ground. Sometimes based >>upon the sunlight, the wings show the spar line but that is a >>construction/finishing issue. >> >>Bobby Muse >>bmuse@mindspring.com > >Bobby, did you also use extra layers of glass or build them "normal?" There >seem to be as many different building techniques on this list as there are >people. > >Mike Taglieri > The outer wings are Diehl wing skins. The inner wing stubs have two layers with four on the leading edge. My Dad's KR has one layer of Dynel(used before fiberglass) and two on the leading edge. I have flown in his KR serveral times and have never noticed any bowing in the skin. If I did, I don't believe that I would fly in his KR. I remember the first few times that I flew with him that I had the fear that the wings would fall off. So, I watched the wings.....a lot! Bobby Muse bmuse@mindspring.com ------------------------------ Date: Wed, 30 Apr 1997 20:59:47 +0700 From: "L.Palaniappan" Subject: Re: KR: Fuselage Widening At 08:21 PM 4/29/97 -0500, you wrote: >Mike Mims wrote: > Personally, I widened mine about >3 inches, which is perfect for me and my wife. And I widened it at the >the shoulder for ergonomic and aerodynamic reasons, as Don Reid stated. Doubts doubts doubts, Many have widened several inches at the shoulder of the fuse. Does this involve a corresponding widening of the fuse base? If so in what proportions? Will the length of the fuselage from firewall to tail remain the same, or become shorter due to increased curvature at the shoulders ? Please set my logic straight, that's all. Thank you. Palani Malaysia. ------------------------------ Date: Wed, 30 Apr 1997 10:34:06 -0400 (EDT) From: LVav8r@aol.com Subject: Re: KR: Fire Sensors In a message dated 97-04-29 17:07:51 EDT, you write: << I think it's a good idea however, any warning is better than none. >But false alarms would be a real pain. Show me a simple installation >and I'll put them in my KR. > > - Ross >> I plan to put a verrrrrrry simple fire detector in mine. MY EYES & MY NOSE!!! Tom Kilgore ------------------------------ Date: Wed, 30 Apr 1997 10:34:32 -0700 From: Donald Reid Subject: Re: KR: Fuselage Widening L.Palaniappan wrote: > > At 08:21 PM 4/29/97 -0500, you wrote: > >Mike Mims wrote: > > > Personally, I widened mine about > >3 inches, which is perfect for me and my wife. And I widened it at the > >the shoulder for ergonomic and aerodynamic reasons, as Don Reid stated. > > Doubts doubts doubts, > > Many have widened several inches at the shoulder of the fuse. > Does this involve a corresponding widening of the fuse base? If so > in what proportions? > > Will the length of the fuselage from firewall to tail remain the same, > or become shorter due to increased curvature at the shoulders ? > > Please set my logic straight, that's all. Thank you. > > Palani > Malaysia. I widened mine proportionally at the fuselage bottom. If you don't, the top longeron bow will increase. The overall length does decrease, but only a tiny amount. Don Reid donreid@erols.com ------------------------------ Date: Wed, 30 Apr 1997 10:48:13 -0700 From: Donald Reid Subject: Re: KR: Fuselage Widening Owen Davies wrote: > > Does anyone have a good grip on how much difference a wider > fuselage makes to your cruise and top end? > > Many thanks. > > Owen Davies In classical aeronautical theory, a relatively blunt streamlined object has a minimum drag with a length to thickness ratio of about 3 or 4 to 1. Our aircraft are less than that by a considerable amount, so a small increase will not adversely affect the fuselage drag, and might even help. This is one reason why the Questair Venture looks like an egg with wings and goes so fast. The wing to fuselage interference might be affected, but not by a lot. The wetted surface area is not increased by widening (surface in contact with the air stream), and the basic smooth finish is not increased, so there should not be a significant change in overall drag. Don Reid donreid@erols.com ------------------------------ Date: Wed, 30 Apr 1997 08:57:58 -0700 From: Micheal Mims Subject: Re: KR: aileron linkage At 02:51 AM 4/30/97 -0500, you wrote: >Recommendation: > Drill a locking pin hole through eack of the belcranks and mounting brackets so that they can be locked into the proper angle/position. Once locked, all of the aileron cables and push rods can be proper lenghtened and adjusted.Bobby Muse >bmuse@mindspring.com > > Wow, I did this but forgot to mention it! I was thinking back to the days when I rigged flight controls on the F-4S in the USMC and that's how we did it, so I figured if its good enough for McDonald Douglas its good enough for the KR! :-) Micheal Mims ------------------------------ Date: Wed, 30 Apr 1997 09:11:19 -0700 From: Micheal Mims Subject: Re: KR: Fuselage Widening At 08:59 PM 4/30/97 +0700, you wrote: >At 08:21 PM 4/29/97 -0500, you wrote: >>Mike Mims wrote: >> > Personally, I widened mine about >>3 inches, which is perfect for me and my wife. And I widened it at the >>the shoulder for ergonomic and aerodynamic reasons, as Don Reid stated. > > >Doubts doubts doubts, > >Many have widened several inches at the shoulder of the fuse. >Does this involve a corresponding widening of the fuse base? If so >in what proportions? > >Will the length of the fuselage from firewall to tail remain the same, >or become shorter due to increased curvature at the shoulders ? > >Please set my logic straight, that's all. Thank you. > Boy, sometimes these editing jobs on the posting really get things switched around! I think Mark Langford posted the statement above not me. I widened mine 4 inches top and bottom at the widest points on the plans and left the firewall and everything else the same. If you widen the top and not the bottom I hope you have a small butt!! Im sure the firewall angle may have changed a little and my KR could be 1/2 inch shorter but who cares? At least two people can fit in mine! I plan on adjusting my thrust line with washers anyway after the project is complete. Micheal Mims ------------------------------ Date: Wed, 30 Apr 1997 14:41:37 -0400 From: Patrick Flowers Subject: KR: Funny With apologies to KR purists, I offer the following which was found on rec.aviation.homebuilt: > A Microsoft engineer gets drafted and shipped off to basic training. > While at the rifle range the engineer is given a rifle and some > ammunition. Said engineer then sends three shots downrange and is > informed that nothing hit the target. Puzzled, our hero takes out > the magazine, checks the chamber, cycles the action and reloads. > Three more shots are fired off and the same message comes from > downrange -- no hits. Now the engineer seems perplexed. He puts > his finger ovr the barrel and lets loose a round. The tip of his > finger is taken off in a spray of red mist. He then yells down > to the sighting bunkers, "It's leaving here just fine. The problem > must be on your end!" - -- Patrick Flowers Mailto:patri63@ibm.net ------------------------------ Date: Wed, 30 Apr 1997 11:46:49 -0700 From: Ross Youngblood Subject: Re: KR: Fuselage Skin Austin Clark wrote: > Michael, > > Did you make your scarf joints in the plywood before installation or during > installation? I am considering making the scarf joints and letting them > cure before installing the skin. > > Austin Clark Austin, This is what I did, it worked out well. -- Ross ------------------------------ Date: Wed, 30 Apr 97 19:38:32 GMT From: mathewrz@iafrica.com (Rob Matthews) Subject: Fw: RE: Re: KR: RAF48 incidence, trim Rob Matthews Have a nice day South Africa email mathewrz@iafrica.com - ----------------------------Forwarded Message-------------------------------- > Does Bill have the aerofoil data for the RAF 48? I am sure that if one were > to take a look at Pazmany's Light Aircraft Design book, one would find the > method of calculating incidence angle. My thinking on incidence is; 1) To > generate Cl max at the stall speed of around 55mph without knocking the tail > on the runway. This is vital in a tricycle; in a tail tragger - to produce a > three point landing, I would like a balance between the wing angle of attack > at Cl max and the stall speed. 2) If I had rigged my wing at -2 degrees. The > wing would still stall at Cl max and the related angle of attack BUT can you > imagine the stall attitude from the pilot seat! Dont kid yourselves, 5 > degrees is alot !! In designing my aircraft (not a KR2), I used the > relationship between the normal line of sight from the pilot, the fuselage > attitude and the angle of incidence of the wing at its Cl max, to determine > the rigging angle. > Steve > ---------- > From: SMTP1@K1 - Server@Servers[] > To: > Subject: Fw: Re: KR: RAF48 incidence, trim > Date: Monday, April 28, 1997 2:59PM > > -- > Rob Matthews Have a nice day > South Africa > email mathewrz@iafrica.com > ----------------------------Forwarded Message-------------------------------- > > > smithr wrote: > > > > > > Forgive me for beating this horse. > > > Incidence means little when the wing is flying. And we are only talking > > > about 3.5 degrees anyhow. I suspect that at equilibrium cruise (with 1 > > > person) the KR needs only a fraction of 1 degree, maybe about 0.5 deg to > > > generate enough lift. This means the fuselage is pointing down only 3 > > > degrees. This doesn't seem like much and probably improves visibility. > > > In a landing descent at 3 degrees, the KR fuselage would appear to be > > > pointing down 6 degrees (sounds pretty normal to me). I don't see a > > > problem. > > > I realize that drag is probably not optimized. But the > > > important concerns are whether or not enough trim is available (between > > > a 1 or 2 person load) and the relationship of the wing incidence (3.5 > > > deg) to the horizontal stabilizer incidence (0 deg ) which hopefully > > > stabilizes the plane. Will less than 3.5 decalage stabilize the KR? > > > I will probably lower my incidence very little to 3 deg. > > > Comments anyone? > > > > > > Bob Smith, KR2S , no aerodynamics credentials whatsoever > > > > Bob, another small point on incidence: the root incidence is 3 degrees > > however the tip incidence is of course less. The net result is the > > average incidence is less than 3 degrees. Also the RAF 48 aerofoil has > > a zero lift angle of attack of -2 degrees so the wing/body incidence in > > flight is hard to actually determine theoretically and practically. > > > > The required angle of attack (to support the weight will vary according > > to speed of course so not only has washout, angle of zero lift to be > > considered, but also the speed that you are setting the wing incidence > > for. > > > > An equally important factor is the engine thrust line. If this is not > > set optimally to take into account body angle at cruise and upwash in > > front of the wing, then the efficiency will be reduced affecting cruise > > speed for a given power setting. > > > > Well that's my 2 cents worth. > > > > bill > > > ------------------------------ End of krnet-l-digest V1 #5 ***************************