From: To: Subject: krnet Digest 4 Sep 2001 07:29:08 -0000 Issue 283 Date: Tuesday, September 04, 2001 12:29 AM krnet Digest 4 Sep 2001 07:29:08 -0000 Issue 283 Topics (messages 6722 through 6751): Re: Juno Mail 6722 by: virgnvs.juno.com WAF stress analysis 6723 by: Oscar Zuniga 6725 by: Donald Reid 6728 by: Serge F. VIDAL flight data- Revmaster 2100D/KR-2S 6724 by: Oscar Zuniga 6727 by: rwmoore Whelen tail lights 6726 by: Mark Langford Wheel vs Tailwheel landings 6729 by: GoFlySlow2.aol.com 6730 by: Peter Nauta 6732 by: Philip J. Visconti 6738 by: virgnvs.juno.com gear height 6731 by: Mark Langford 6734 by: David Mullins landing the KR 6733 by: krwr1.zoominternet.net composite question 6735 by: drewlive.prodigy.net 6736 by: Mark Langford 6739 by: Jerry Mahurin 6742 by: Robert X. Cringely KR1 gear 6737 by: clair boyd 6740 by: Greg S Martin 6743 by: Robert X. Cringely 6745 by: virgnvs.juno.com 6746 by: Daniel Heath Re: 15 hours to convert! 6741 by: JC Marais Re: KR2 boat 6744 by: moat1 Re: nose gear 6747 by: michael beck flow lines? 6748 by: Mark Langford 6750 by: Serge F. VIDAL Re: Volunteer? Hell, we're the Vol state... 6749 by: CS A direct quote...from Tony Bingelis... 6751 by: CS Administrivia: To subscribe to the digest, e-mail: To unsubscribe from the digest, e-mail: To post to the list, e-mail: ---------------------------------------------------------------------- Date: Sun, 2 Sep 2001 17:45:21 -0400 To: viscan@juno.com From: virgnvs@juno.com Cc: krnet@mailinglists.org Subject: Re: KR> Juno Mail Message-ID: <20010902.175020.-126695.0.virgnvs@juno.com> I have Juno and got this, Virg On Sun, 2 Sep 2001 13:20:22 -0400 "Philip J. Visconti" writes: > Yesterday, Juno sent me msg saying they were having problem with > their > E-mail. > > Haven't received any since then. I'll see what happens with this. > > Phil > ________________________________________________________________ > GET INTERNET ACCESS FROM JUNO! > Juno offers FREE or PREMIUM Internet access for less! > Join Juno today! For your FREE software, visit: > http://dl.www.juno.com/get/tagj. > > --------------------------------------------------------------------- > To post to the list, email: krnet@mailinglists.org , or "reply all" > > To UNsubscribe, e-mail: krnet-unsubscribe@mailinglists.org > For additional commands, e-mail: krnet-help@mailinglists.org > > See the KRNet archives at http://www.escribe.com/aviation/krnet/ . > AOL and Compuserve do NOT pass KRNet email, so use some other > system! > > ------------------------------ Date: Sun, 02 Sep 2001 23:11:08 To: krnet@mailinglists.org From: "Oscar Zuniga" Subject: WAF stress analysis Message-ID: Hello, netters; As usual, I'm way behind in my reading, so I just got around to reading the EAA Experimenter from July (same edition that has the story by Pat Panzera on his beautiful Corvair engine), and noticed that KRNet's very own Don Reid made that issue. Not with a story or pictures, but with a response on the series that they have been running on analyzing stress at a wing attach fitting. The author of the articles responded to a letter that Don wrote about the analysis. I think Don noticed a resemblance between the sample WAF that was being used as an example, and the KR WAF. Way to go, Don. Also, in a little email exchange a few years ago, I thought I was being a know-it-all on taildragger landing technique and I corrected someone who said that upon touching down for landing in a taildragger, they would ease the stick forward to kill lift and plant the mains. Daniel Heath again mentions this in a post from a day or two ago: >The entire time that I flew my KR, I was only able to do a >3 point landing one time. I always did wheel landings and raised >the tail slightly as the mains touched. This was to kill the lift. Well, since I fly taildraggers I was sure that I was right about doing just the opposite... pulling that stick back to plant the mains! The idea is to stall the wing and keep it stalled, put it in a high-drag configuration and make the plane stay that way. I kept muttering to myself that I was right, you guys were wrong about lowering the nose because the airplane is "operating on the backside of the curve" and "in the area of reversed control effect" and produces more drag than lift when you keep increasing the AOA at that point, etc. etc. What never occurred to me was that the KR taildragger's wing may not be stalled when in a 3-point configuration! The light is finally going on in my head, folks. As my daughter would say, I'm going like, DUH! Oscar Zuniga Medford, Oregon mailto: taildrags@hotmail.com website at http://www.geocities.com/taildrags/ _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp ------------------------------ Date: Sun, 02 Sep 2001 20:08:46 -0400 To: krnet@mailinglists.org From: Donald Reid Subject: Re: KR> WAF stress analysis Message-Id: <5.0.2.1.0.20010902200106.00a0aa40@pop.erols.com> --=====================_6261073==_.ALT Content-Type: text/plain; charset="us-ascii"; format=flowed At 11:11 PM 9/2/2001 +0000, Oscar Zuniga wrote: >... reading the EAA Experimenter from July (same edition that has the >story by Pat Panzera on his beautiful Corvair engine), and noticed that >KRNet's very own Don Reid made that issue. Not with a story or pictures, >but with a response on the series that they have been running on analyzing >stress at a wing attach fitting. The author of the articles responded to >a letter that Don wrote about the analysis. Actually, I wrote a reasonably long letter that said he was wrong about one critical area of his design. I listed some references and gave a few calculations. He rephrased the letter a lot to make my comment less damning. I thought about doing an article of rebuttal but I don't really have the time. The short answer is that in a KR style wing fitting, what most of you think of a "holes to make the fitting lighter" are really an important part of the structure. When metal is bolted to wood, things are pretty critical. Continuing to geek... Don Reid mailto:donreid@erols.com Bumpass, Va Visit my web sites at: 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 --=====================_6261073==_.ALT-- ------------------------------ Date: Mon, 3 Sep 2001 08:12:11 +0200 To: "Oscar Zuniga" , From: "Serge F. VIDAL" Subject: RE: KR> WAF stress analysis Message-ID: Oscar, I confirm that stick-forward story. Don't do it, and you get a big bounce, and a frightening one, at that. Now, this applies to power-assisted, wheeled landings. My guess is that doing a wheeled landing on a KR, the aircraft touches down at fairly high speed (85mph in my case), and still has potential to get airborne. In my understanding, the stick forward is actually to prevent the vertical speed to translate into a nose-up attitude. For 3-points landings, which I haven't tried yet, I am fairly sure that the technique would be the same as for any taildragger. Could any expert confirm on that, before I go and test? Serge VIDAL KR2 ZS-WEC Johannesburg, South Africa -----Original Message----- From: Oscar Zuniga [mailto:taildrags@hotmail.com] Sent: 02 September, 2001 11:11 PM To: krnet@mailinglists.org Subject: KR> WAF stress analysis Hello, netters; As usual, I'm way behind in my reading, so I just got around to reading the EAA Experimenter from July (same edition that has the story by Pat Panzera on his beautiful Corvair engine), and noticed that KRNet's very own Don Reid made that issue. Not with a story or pictures, but with a response on the series that they have been running on analyzing stress at a wing attach fitting. The author of the articles responded to a letter that Don wrote about the analysis. I think Don noticed a resemblance between the sample WAF that was being used as an example, and the KR WAF. Way to go, Don. Also, in a little email exchange a few years ago, I thought I was being a know-it-all on taildragger landing technique and I corrected someone who said that upon touching down for landing in a taildragger, they would ease the stick forward to kill lift and plant the mains. Daniel Heath again mentions this in a post from a day or two ago: >The entire time that I flew my KR, I was only able to do a >3 point landing one time. I always did wheel landings and raised >the tail slightly as the mains touched. This was to kill the lift. Well, since I fly taildraggers I was sure that I was right about doing just the opposite... pulling that stick back to plant the mains! The idea is to stall the wing and keep it stalled, put it in a high-drag configuration and make the plane stay that way. I kept muttering to myself that I was right, you guys were wrong about lowering the nose because the airplane is "operating on the backside of the curve" and "in the area of reversed control effect" and produces more drag than lift when you keep increasing the AOA at that point, etc. etc. What never occurred to me was that the KR taildragger's wing may not be stalled when in a 3-point configuration! The light is finally going on in my head, folks. As my daughter would say, I'm going like, DUH! Oscar Zuniga Medford, Oregon mailto: taildrags@hotmail.com website at http://www.geocities.com/taildrags/ _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp --------------------------------------------------------------------- To post to the list, email: krnet@mailinglists.org , or "reply all" To UNsubscribe, e-mail: krnet-unsubscribe@mailinglists.org For additional commands, e-mail: krnet-help@mailinglists.org See the KRNet archives at http://www.escribe.com/aviation/krnet/ . AOL and Compuserve do NOT pass KRNet email, so use some other system! ------------------------------ Date: Sun, 02 Sep 2001 23:25:58 To: krnet@mailinglists.org From: "Oscar Zuniga" Subject: flight data- Revmaster 2100D/KR-2S Message-ID: Netters; After my post regarding VWs for KRs, I got several emails in response. About a year ago, there was a Revmaster 2100D for sale locally, and it was picked up by Al Friesen, a guy here on the Net. He has it flying, and since folks are always looking for data on flying KRs, I am forwarding this info from Al: From: "Al Friesen" Date: Fri, 31 Aug 2001 12:16:34 -0700 I saw your mail on engine size. I bought the 2100D from Terry I think it was, on your advice as to his sale last fall, it flys great on my 2S. I get good climb at 80, 2600rpm cruise is 120, full out at 3300rpm 160. All that with a Props Inc. 55X45 prop. The landings are a bit hairy but controlable. I have 4 CHT and got a hot front right cyl, saw a note on the KR chat about a stainless fuel deflector aft of the carb, same side as the fuel entry and got the temps even on all cyl. She flys great, feels like a Spit in power turns. [The] mixture problem [was that it was] too lean on the right cyls. and I got the fix idea off the net. Because the fuel enters the intake manifold on the left side somebody suggested putting a centering defector aft of the carb on the same side as the fuel jet. The fix was on a Revmaster carb and worked perfectly. I have temps on all cyls so can correct a fuel imbalance. -Al ============ The Revflow carb has a slide in the throat, and when the carb is mounted under the engine with the bore horizontal, the slide opens from one side, which means that one side of the "Y" splitter to each head will see more of the fuel/air mix than the other (until the slide is wide open). Someone came up with the idea of adding a diverter tab of some sort, to deflect more of the fuel to the side of the "Y" opposite the throttle slide opening. Apparently it works. Oscar Zuniga EAA#237232 AOPA#455536 SAA#1001 Medford, Oregon _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp ------------------------------ Date: Mon, 03 Sep 2001 00:20:13 -0400 To: Oscar Zuniga From: rwmoore CC: krnet@mailinglists.org Subject: Re: KR> flight data- Revmaster 2100D/KR-2S Message-ID: <3B9304FD.78B2D9AF@alltel.net> Bill Wood at Foothills Aviation has a Revmaster/turbo/vacuum pump drive system. 706-886-6341 Toccoa, Ga. 30577 Tell him R. W. told you to call. R. W. Moore Oscar Zuniga wrote: > Netters; > > After my post regarding VWs for KRs, I got several emails in response. > About a year ago, there was a Revmaster 2100D for sale locally, and it was > picked up by Al Friesen, a guy here on the Net. He has it flying, and since > folks are always looking for data on flying KRs, I am forwarding this info > from Al: > > From: "Al Friesen" > Date: Fri, 31 Aug 2001 12:16:34 -0700 > > I saw your mail on engine size. I bought the 2100D from Terry I think it > was, on your advice as to his sale last fall, it flys great on my 2S. I get > good climb at 80, 2600rpm cruise is 120, full out at 3300rpm 160. All that > with a Props Inc. 55X45 prop. The landings are a bit hairy but controlable. > I have 4 CHT and got a hot front right cyl, saw a note on the KR chat about > a stainless fuel deflector aft of the carb, same side as the fuel entry and > got the temps even on all cyl. She flys great, feels like a Spit in power > turns. > > [The] mixture problem [was that it was] too lean on the right cyls. and I > got the fix idea off the net. Because the fuel enters the intake manifold > on the left side somebody suggested putting a centering defector aft of the > carb on the same side as the fuel jet. The fix was on a Revmaster carb and > worked perfectly. I have temps on all cyls so can correct a fuel imbalance. > -Al > ============ > The Revflow carb has a slide in the throat, and when the carb is mounted > under the engine with the bore horizontal, the slide opens from one side, > which means that one side of the "Y" splitter to each head will see more of > the fuel/air mix than the other (until the slide is wide open). Someone > came up with the idea of adding a diverter tab of some sort, to deflect more > of the fuel to the side of the "Y" opposite the throttle slide opening. > Apparently it works. > > Oscar Zuniga EAA#237232 AOPA#455536 SAA#1001 > Medford, Oregon > > _________________________________________________________________ > Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp > > --------------------------------------------------------------------- > To post to the list, email: krnet@mailinglists.org , or "reply all" > > To UNsubscribe, e-mail: krnet-unsubscribe@mailinglists.org > For additional commands, e-mail: krnet-help@mailinglists.org > > See the KRNet archives at http://www.escribe.com/aviation/krnet/ . > AOL and Compuserve do NOT pass KRNet email, so use some other system! ------------------------------ Date: Sun, 2 Sep 2001 22:23:45 -0500 To: "KRnet" From: "Mark Langford" Subject: Whelen tail lights Message-ID: <006201c13427$d748dcd0$7000a8c0@athlon600> Somebody asked about tail lights the other day. Here's a picture of Bobby Muse's, http://home.hiwaay.net/~langford/kbm4.jpg , which appears to be a Whelen like the one I'm using. It's only about an 1.625" in diameter. I originally located mine along the same plane as the horizontal stabilizer, but then it occurred to me that the elevator might get "caught up" on it, so I moved it up a few inches. Otherwise, mine's going to look a lot like this one. Mark Langford, Huntsville, Alabama mailto:langford@hiwaay.net see KR2S project N56ML at http://home.hiwaay.net/~langford ------------------------------ Date: Mon, 3 Sep 2001 03:06:16 EDT To: krnet@mailinglists.org From: GoFlySlow2@aol.com CC: svidal@icon.co.za Subject: Wheel vs Tailwheel landings Message-ID: <8c.c129c57.28c485e8@aol.com> --part1_8c.c129c57.28c485e8_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit I have found the landing characteristics of my particular KR-2 to be better in the tailwheel first scenario. I approach on final at 80mph. Short final at idle gradually decreasing speed to 70-60 mph. I fly the plane at idle on short final to just above the ground.(Approx 3-5 feet) As speed bleeds off, continue to keep her just off the ground (without ballooning) by raising the the nose. Speed continues to bleed off. The appearance/attitude will be like that of the plane at taxi or slightly higher. Maintain that attitude and feel the tail wheel touch first followed immediately by the mains. Gently, smoothly and slowly give full back stick pressure and allow the plane to slow down. My touch down speeds are 45-50 mph. and feel VERYmuch more stable on roll out than when landing on the mains. Also, Much less runway is used up. My KR-2 Stats - http://www.angelfire.com/biz6/MFM/inflight.JPG http://www.angelfire.com/biz6/MFM/JeanieKR2.jpg 1835 HAPI engine with "stinger exhaust" single mag, Bendix Zenith carb Great American 52x44 prop Standard retracts Extended wing 23ft Extended Fuse by 14 in 4 in diameter extended pneumatic tailwheel (large, not pretty but works great) Empty Wt. 667 lbs Climb - at sea level, F- 68 Pilot 190lbs Passenger 140lbs fuel 60lbs - 700-800 ft/min at 90 -100mph 2800rpm (at Torrance Zamperinni, Ca. with Kevin Lampon who asked for a ride on this list)) Stall - power on 45mph power off 50mph cruise 145 -150mph 3200rpm Hope this sheds a little insight. Chuck Scrivner Wish I could go to the "Gathering" --part1_8c.c129c57.28c485e8_boundary-- ------------------------------ Date: Mon, 3 Sep 2001 13:08:05 +0200 To: "Krnet@Mailinglists. Org" From: "Peter Nauta" Subject: RE: KR> Wheel vs Tailwheel landings Message-ID: I have no actual tailwheel time or time in a KR as PIC, but want to relay what's been said over here about tailwheel KR's. The first and only KR2S in the Netherlands is a taildragger. It was badly damaged some 2 weeks ago during a landing which went wrong. The craft only has one set of controls, the throttle is on the left side, so the instructor had no way of assisting. The PIC had his first landing in the left seat and confused throttle with stick, so after flaring too high, things got hairy and the plane flipped. No personal injuries were sustained, but major repairs have to be done. Two things which apparently are going to change are that trigear will be fitted and dual controls are going in in such a way that both pilots have equal opportunity. An instructor who flew the bird on previous occasions commented that ground effect is the biggest problem. He said that while flaps help getting the speed down, one may actually consider retracting these as soon as the plane is in ground effect. Another suggestion was to fit longer gear legs. How long these need to be I dare not say. A belly board with holes or spoilers are some other suggestions. Retracting the flaps during such critical phase is not something I plan to attempt. I have always been convinced of the benefits of trigear, and even more so after this episode and these threads. Another decision also stands firm: a reduction drive, so the prop at idle won't contribute to elongated floating (idling the engine at 1000rpm actually means a prop running at less than 500rpm). Another way may be an adjustable prop. I know a lot of KR's are tailwheel, and many pilots successfully fly these without incidence, it is my opinion that a low time pilot should stay away from it. Regards, Peter Nauta PS. Opinions are just that... -----Original Message----- From: GoFlySlow2@aol.com [mailto:GoFlySlow2@aol.com] Sent: maandag 3 september 2001 9:06 To: krnet@mailinglists.org Cc: svidal@icon.co.za Subject: KR> Wheel vs Tailwheel landings I have found the landing characteristics of my particular KR-2 to be better in the tailwheel first scenario. I approach on final at 80mph. Short final at idle gradually decreasing speed to 70-60 mph. I fly the plane at idle on short final to just above the ground.(Approx 3-5 feet) As speed bleeds off, continue to keep her just off the ground (without ballooning) by raising the the nose. Speed continues to bleed off. The appearance/attitude will be like that of the plane at taxi or slightly higher. Maintain that attitude and feel the tail wheel touch first followed immediately by the mains. Gently, smoothly and slowly give full back stick pressure and allow the plane to slow down. My touch down speeds are 45-50 mph. and feel VERYmuch more stable on roll out than when landing on the mains. Also, Much less runway is used up. My KR-2 Stats - http://www.angelfire.c om/biz6/MFM/inflight.JPG http://www.angelfire.com/biz6/MFM/JeanieKR2.jpg 1835 HAPI engine with "stinger exhaust" single mag, Bendix Zenith carb Great American 52x44 prop Standard retracts Extended wing 23ft Extended Fuse by 14 in 4 in diameter extended pneumatic tailwheel (large, not pretty but works great) Empty Wt. 667 lbs Climb - at sea level, F- 68 Pilot 190lbs Passenger 140lbs fuel 60lbs - 700-800 ft/min at 90 -100mph 2800rpm (at Torrance Zamperinni, Ca. with Kevin Lampon who asked for a ride on this list)) Stall - power on 45mph power off 50mph cruise 145 -150mph 3200rpm Hope this sheds a little insight. Chuck Scrivner Wish I could go to the "Gathering" ------------------------------ Date: Mon, 3 Sep 2001 09:38:31 -0400 To: GoFlySlow2@aol.com From: "Philip J. Visconti" Cc: krnet@mailinglists.org, svidal@icon.co.za Subject: Re: KR> Wheel vs Tailwheel landings Message-ID: <20010903.093832.-89215.0.viscan@juno.com> Chuck, Sounds good. How much runway used ? With and without passenger. Phil ________________________________________________________________ GET INTERNET ACCESS FROM JUNO! Juno offers FREE or PREMIUM Internet access for less! Join Juno today! For your FREE software, visit: http://dl.www.juno.com/get/tagj. ------------------------------ Date: Mon, 3 Sep 2001 16:15:28 -0400 To: pnauta@xs4all.nl From: virgnvs@juno.com Cc: krnet@mailinglists.org Subject: Re: KR> Wheel vs Tailwheel landings Message-ID: <20010903.161733.-288249.0.virgnvs@juno.com> Find Vs add 10% and fly that on final. Practice this with spot landings. Be the best pilot on the field. Virg On Mon, 3 Sep 2001 13:08:05 +0200 "Peter Nauta" writes: > I have no actual tailwheel time or time in a KR as PIC, but want to > relay > what's been said over here about tailwheel KR's. > > The first and only KR2S in the Netherlands is a taildragger. It was > badly > damaged some 2 weeks ago during a landing which went wrong. The > craft only > has one set of controls, the throttle is on the left side, so the > instructor > had no way of assisting. The PIC had his first landing in the left > seat and > confused throttle with stick, so after flaring too high, things got > hairy > and the plane flipped. No personal injuries were sustained, but > major > repairs have to be done. Two things which apparently are going to > change > are that trigear will be fitted and dual controls are going in in > such a way > that both pilots have equal opportunity. > > An instructor who flew the bird on previous occasions commented that > ground > effect is the biggest problem. He said that while flaps help > getting the > speed down, one may actually consider retracting these as soon as > the plane > is in ground effect. Another suggestion was to fit longer gear > legs. How > long these need to be I dare not say. A belly board with holes or > spoilers > are some other suggestions. Retracting the flaps during such > critical phase > is not something I plan to attempt. > > I have always been convinced of the benefits of trigear, and even > more so > after this episode and these threads. Another decision also stands > firm: a > reduction drive, so the prop at idle won't contribute to elongated > floating > (idling the engine at 1000rpm actually means a prop running at less > than > 500rpm). Another way may be an adjustable prop. I know a lot of > KR's are > tailwheel, and many pilots successfully fly these without incidence, > it is > my opinion that a low time pilot should stay away from it. > > Regards, > > Peter Nauta > . Opinions are just that... > > > -----Original Message----- > From: GoFlySlow2@aol.com [mailto:GoFlySlow2@aol.com] > Sent: maandag 3 september 2001 9:06 > To: krnet@mailinglists.org > Cc: svidal@icon.co.za > Subject: KR> Wheel vs Tailwheel landings > > > I have found the landing characteristics of my particular KR-2 to be > better > in the tailwheel first scenario. > > I approach on final at 80mph. > Short final at idle gradually decreasing speed to 70-60 mph. > I fly the plane at idle on short final to just above the > ground.(Approx 3-5 > feet) As speed bleeds off, continue to keep her just off the ground > (without > ballooning) by raising the the nose. Speed continues to bleed off. > The > appearance/attitude will be like that of the plane at taxi or > slightly > higher. Maintain that attitude and feel the tail wheel touch first > followed > immediately by the mains. Gently, smoothly and slowly give full > back stick > pressure and allow the plane to slow down. My touch down speeds are > 45-50 > mph. and feel VERYmuch more stable on roll out than when landing on > the > mains. > Also, Much less runway is used up. > My KR-2 Stats - HREF="http://www.angelfire.com/biz6/MFM/inflight.JPG">http://www.angelfir e.c > om/biz6/MFM/inflight.JPG HREF="http://www.angelfire.com/biz6/MFM/JeanieKR2.jpg"> > http://www.angelfire.com/biz6/MFM/JeanieKR2.jpg > 1835 HAPI engine with "stinger exhaust" single mag, Bendix Zenith > carb > Great American 52x44 prop > Standard retracts Extended wing 23ft Extended Fuse by 14 in > 4 in diameter extended pneumatic tailwheel (large, not pretty but > works > great) > Empty Wt. 667 lbs > Climb - at sea level, F- 68 Pilot 190lbs Passenger 140lbs fuel > 60lbs - > 700-800 ft/min at 90 -100mph 2800rpm (at Torrance Zamperinni, Ca. > with > Kevin > Lampon who asked for a ride on this list)) > Stall - power on 45mph power off 50mph > cruise 145 -150mph 3200rpm > Hope this sheds a little insight. > Chuck Scrivner > Wish I could go to the "Gathering" > > > > --------------------------------------------------------------------- > To post to the list, email: krnet@mailinglists.org , or "reply all" > > To UNsubscribe, e-mail: krnet-unsubscribe@mailinglists.org > For additional commands, e-mail: krnet-help@mailinglists.org > > See the KRNet archives at http://www.escribe.com/aviation/krnet/ . > AOL and Compuserve do NOT pass KRNet email, so use some other > system! > > ------------------------------ Date: Mon, 3 Sep 2001 07:20:26 -0500 To: "KRnet" From: "Mark Langford" Subject: gear height Message-ID: <007201c13472$d050b1f0$7000a8c0@athlon600> I wrote this yesterday, but hadn't hit "send" yet. But after reading Peter's message, I think it's time has come. Maybe Ed will comment on his Grove gear. I've been thinking about gear height, Ed's use of the Grove gear, and was wondering how tall the Grove gear would make a KR. The measurements are on their web site, and it would basically make my KR2S 3.5" taller than the Diehl gear than it sits on now, which is even taller than the retracts. If I were to do it again, I believe I'd start with the Grove. But I've already made my own 3" gear extensions, which are detailed at http://home.hiwaay.net/~langford/kgear.html . The extra height allows more prop clearance and gets closer to full stall landing capability. Amazingly, they shouldn't cost any extra drag, since the gear leg will now intersect at the top of the wheel pant rather than at the middle. But I won't install them until winter when all the composite fun is over... Mark Langford, Huntsville, Alabama mailto:langford@hiwaay.net see KR2S project N56ML at http://home.hiwaay.net/~langford ------------------------------ Date: Mon, 03 Sep 2001 12:27:28 -0400 From: David Mullins CC: KRnet Subject: Re: KR> gear height Message-ID: <3B93AF70.74E83A1@mediaone.net> Mark and Netters, Ed Blocher asked me a while ago for the dimensions of my Grove main gear. The thickness and width were calculated by Robbie Grove as 4.5" wide and 7/8" thick. I calculated the height and track width by taking the thrust line of the KR, after fitting the Corvair engine in place, I then added a 60" Warp drive propeller. I gave the prop 9" of clearance. In my CAD program I had drawn a line representing the ground. I measured the wheels and tires. I put those in which gave me the axle height. The dimension from the axle centerline to the top face of the gear was 18". I wanted the wheels to track as wide as possible but still be able to fit an eight foot wide trailer. The width of the Tracy O'Brien brakes, wheels, axles and the MF-3 wheel pants were measured. Those figures were included to get me the final gear width of 66". This gives me a wheel track centerline of 7 feet. My Main Gear bracket is a simple "L" shape made from 1/4" 4130 plate 3" wide. I welded 1/8" 4130 plate as sides to it and a 2" wide stiffener across the third side of the angle. There were five 3/8" holes drilled into the bracket. One at the top spar cap, Two at the bottom spar cap, and two on the bottom of the "L" to fit the radius blocks that the main gear actually bolt to. The nose gear I am making from 4130 tubing and plate following the basic design of a Grumman Yankee's. The nose wheel pant is one made by Ken Boyer. Which I believe is from a mold of Mark's wheel pant. The Nose gear mount was incorporated into the Corvair motor mount. I used a 1.250" .120 wall 4130 tube mounted on a 45 degree angle. In to that I used a 1" .120 wall 4130 tube. This tube also had a 45 degree bend in it. This bend will make the tube run vertically. A trailing link fork will slide on to this tube. The links below will let you see what has been completed and what is planned. http://n323xl.iwarp.com/bllandinggear1.htm - Main Landing Gear http://n323xl.iwarp.com/bllandinggear4.htm - Pictures of Yankee nose gear http://n323xl.iwarp.com/yankeenosegear.htm - Diagram of a Yankee Gathering bound, Dave Mullins Nashua, New Hampshire http://n323xl.iwarp.com/ mailto:n323xl@mediaone.net Mark Langford wrote: > I wrote this yesterday, but hadn't hit "send" yet. But after reading > Peter's message, I think it's time has come. Maybe Ed will comment on his > Grove gear. > > I've been thinking about gear height, Ed's use of the Grove gear, and was > wondering how tall the Grove gear would make a KR. The measurements are on > their web site, and it would basically make my KR2S 3.5" taller than the > Diehl gear than it sits on now, which is even taller than the retracts. If > I were to do it again, I believe I'd start with the Grove. > > But I've already made my own 3" gear extensions, which are detailed at > http://home.hiwaay.net/~langford/kgear.html . The extra height allows more > prop clearance and gets closer to full stall landing capability. Amazingly, > they shouldn't cost any extra drag, since the gear leg will now intersect at > the top of the wheel pant rather than at the middle. But I won't install > them until winter when all the composite fun is over... > > Mark Langford, Huntsville, Alabama > mailto:langford@hiwaay.net > see KR2S project N56ML at http://home.hiwaay.net/~langford ------------------------------ Date: Mon, 3 Sep 2001 10:01:49 -0400 To: krnet@mailinglists.org From: krwr1@zoominternet.net Subject: landing the KR Message-ID: <3B93550D.14533.722093@localhost> HI In 1500 hr's in the KR, this always worked for me. I used what some called the navy style of landing. I tried to touched down on the tailwheel first, so that when the mains touched, the KR was done flying. If the gear on the KR were higher, you could get a higher angle of attack, and a slower landing speed. I made wheel landings in higher winds or cross winds. I made the wheel landings with the tail a little low, and as soon as the mains touched I relaxed the back pressure and then a little forward pressure. I even used the brakes at times with the tail up at higher speeds to slow down when the end of the runway was coming up.(I do not recommend this, but it saved my butt a couple of times). Bill Reents krwr1@zoominternet.net ------------------------------ Date: Mon, 03 Sep 2001 12:42:42 -0500 To: krnet@mailinglists.org From: drewlive@prodigy.net Subject: composite question Message-Id: I have decided to use Kevlar to save some weight, but I know idea how much to use. It's been a week since I have emailed DuPont and haven't resieved a reply. Ok, I was going to make a 3ply, 8oz, Bi-directional, glass fabric. I know what the specs are for the glass. What I don't know is how should I do the Kevlar. Do I need to keep it 3ply, or can I use 2 or even 1 ply? There seems to be three styles that I can find, all of which are stronger than glass. Is it ok to use the 1.5 oz on place of the 8oz glass or shoul I stick with the 5 oz. Really what I am trying to say does any one know a good site that can help me convert from glass to Kevlar? Drew ------------------------------ Date: Mon, 3 Sep 2001 12:51:35 -0500 To: From: "Mark Langford" Subject: Re: KR> composite question Message-ID: <082101c134a1$13164490$7000a8c0@athlon600> > I have decided to use Kevlar to save some weight, but I know idea how > much to use. It's been a week since I have emailed DuPont and haven't > resieved a reply. Below is a "composite" of several replies that I've made on KRNet regarding Kevlar and carbon fiber. My main point is that Kevar has practically no place on an airplane other than the cowling (for noise damping) or inside the cockpit (for penetration resistance), but not places where you want strength and stiffness, that's the place for carbon fiber. And if you don't believe it's hard to work with, you need to buy a yard and experience it for yourself before you buy a whole bunch of it for your project! The opportunities to save weight using either Kevlar or carbon fiber aren't all that great, since most of the plane is covered with one layer of whatever cloth you use, and both KR glass and the CF that I used weigh the same. What you CAN get is much stronger parts. The weight savings will be in places where you use several layers, like the canopy frame or wing walks. I'd also use it on ailerons and elevators for flutter resistance. Below is something I posted a while back, again. I think there's a reason why Kevlar is so cheap lately. Also, from "Composite Aircraft Design" by Hollman: 1) "Although fiberglass is the least expensive material, graphite fibers are the most promising for aircraft structures because of their low weight, high strength, and high stiffness as shown in Figure 3. The Starship and Voyager are completely built out of graphite and honeycomb and we can expect to see more and more complete aircraft built of this material." 2) "...this is especially true for Kevlar, which has a tensile strength of 60,000 psi and a compressive strength of 23,000 psi. Because of this low compressive strength, Kevlar is almost solely used for fairings, wheel pants, engine cowls, and other fairings in aircraft structures." 3) "However, because of Kevlar's low crompression strength, Kevlar has found limited structural application in aircraft primary structures. Kevlar is difficult to work with and special tools are needed. The above quotes are not where I formed my opinion about carbon fiber vs Kevlar, just the first ones I came across to support my argument. Engineering data from many different sources is where I formed my "opinion". Personally, there's no amount of benefits of Kevlar that could possibly offset the frustration of trying to work with it. That one little "tracer" thread on carbon fiber rolls has driven me almost to insanity (well, maybe ALL the way, many would argue). That thread invariably ends up on the overlapping joints where there's a material overlap (like wings). Once you sand that little thread, all the fibers stick up, and refuse to go away. With CF or glass they just sand right off. With Kevlar, you're gonna have to sand that thread entirely away, or have a really ugly joint that looks like a line of fuzz. I eventually buried it under Aeropoxy Lite, but in the future, I'll always ensure that the overlap is ON TOP of that thread, rather than below it. I know an engineer who built a Defiant. He built the first cowling out of Kevlar, and the second out of carbon fiber. He swore he'd never touch Kevlar again. And from another post of Kevlar vs carbon fiber: While I can't lay my hands on any tables of comparative strengths at the moment (I could, but I'm really not in the mood to do any more homework at the moment), from memory I'll say that carbon fiber does fail quickly, but much further up the strength curve than the point at which fiberglass fails, so it is in fact stronger than glass. But you're still talking about force levels like you'd experience in a crash here. The point of using carbon fiber is reduced weight for the same strength as glass, or improved strength with the same weight. Last time I looked, 282 carbon fiber has a strength to weight ratio about 3-5 times higher than regular 7533 "KR" glass, but then it also costs 6 times as much. And let the record show that I'm not saying the KR2S even needs ANY carbon fiber, but it's a great way to make things stronger and stiffer while saving weight in the process. Mark Langford, Huntsville, Alabama mailto:langford@hiwaay.net see KR2S project N56ML at http://home.hiwaay.net/~langford ------------------------------ Date: Mon, 03 Sep 2001 16:37:33 -0400 To: "Mark Langford" , From: "Jerry Mahurin" Subject: Re: KR> composite question Message-ID: All, Just for your information: Kevlar was used as the motor mount plate between the Onan engine and the firewall bulkhead. I suppose it was for the slight dampening effect. All I really know is that it is a bit*h to machine (drill, cut, etc.). Of course, that was in the early '80's late 70's; but Kevlar is kevlar. It makes good tire cords.... Jerry Mahurin Lugoff, SC On Mon, 3 Sep 2001 12:51:35 -0500 "Mark Langford" wrote: > > I have decided to use Kevlar to save some weight, but I > know idea how > > much to use. It's been a week since I have emailed > DuPont and haven't > > resieved a reply. > > Below is a "composite" of several replies that I've made > on KRNet regarding > Kevlar and carbon fiber. My main point is that Kevar has > practically no > place on an airplane other than the cowling (for noise > damping) or inside > the cockpit (for penetration resistance), but not places > where you want > strength and stiffness, that's the place for carbon > fiber. And if you > don't believe it's hard to work with, you need to buy a > yard and experience > it for yourself before you buy a whole bunch of it for > your project! > > The opportunities to save weight using either Kevlar or > carbon fiber aren't > all that great, > since most of the plane is covered with one layer of > whatever cloth you use, > and both KR glass and the CF that I used weigh the same. > What you CAN get > is much stronger parts. The weight savings will be in > places where you use > several layers, like the canopy frame or wing walks. I'd > also use it on > ailerons and elevators for flutter resistance. Below is > something I posted > a while back, again. I think there's a reason why Kevlar > is so cheap > lately. > > Also, from "Composite Aircraft Design" by Hollman: > > 1) "Although fiberglass is the least expensive material, > graphite fibers > are the most promising for aircraft structures because of > their low weight, > high strength, and high stiffness as shown in Figure 3. > The Starship and > Voyager are completely built out of graphite and > honeycomb and we can expect > to see more and more complete aircraft built of this > material." > > 2) "...this is especially true for Kevlar, which has a > tensile strength of > 60,000 psi and a compressive strength of 23,000 psi. > Because of this low > compressive strength, Kevlar is almost solely used for > fairings, wheel > pants, engine cowls, and other fairings in aircraft > structures." > > 3) "However, because of Kevlar's low crompression > strength, Kevlar has > found limited structural application in aircraft primary > structures. Kevlar > is difficult to work with and special tools are needed. > > The above quotes are not where I formed my opinion about > carbon fiber vs > Kevlar, just the first ones I came across to support my > argument. > Engineering data from many different sources is where I > formed my "opinion". > Personally, there's no amount of benefits of Kevlar that > could possibly > offset the frustration of trying to work with it. That > one little "tracer" > thread on carbon fiber rolls has driven me almost to > insanity (well, maybe > ALL the way, many would argue). That thread invariably > ends up on the > overlapping joints where there's a material overlap (like > wings). Once you > sand that little thread, all the fibers stick up, and > refuse to go away. > With CF or glass they just sand right off. With Kevlar, > you're gonna have > to sand that thread entirely away, or have a really ugly > joint that looks > like a line of fuzz. I eventually buried it under > Aeropoxy Lite, but in the > future, I'll always ensure that the overlap is ON TOP of > that thread, rather > than below it. > > I know an engineer who built a Defiant. He built the > first cowling out of > Kevlar, and the second out of carbon fiber. He swore he'd > never touch > Kevlar again. > > And from another post of Kevlar vs carbon fiber: > > While I can't lay my hands on any tables of comparative > strengths at the > moment (I could, but I'm really not in the mood to do any > more homework at > the moment), from memory I'll say that carbon fiber does > fail quickly, but > much further up the strength curve than the point at > which fiberglass fails, > so it is in fact stronger than glass. But you're still > talking about force > levels like you'd experience in a crash here. The point > of using carbon > fiber is reduced weight for the same strength as glass, > or improved strength > with the same weight. Last time I looked, 282 carbon > fiber has a strength > to weight ratio about 3-5 times higher than regular 7533 > "KR" glass, but > then it also costs 6 times as much. And let the record > show that I'm not > saying the KR2S even needs ANY carbon fiber, but it's a > great way to make > things stronger and stiffer while saving weight in the > process. > > Mark Langford, Huntsville, Alabama > mailto:langford@hiwaay.net > see KR2S project N56ML at http://home.hiwaay.net/~langford > > > > > > --------------------------------------------------------------------- > To post to the list, email: krnet@mailinglists.org , or > "reply all" > > To UNsubscribe, e-mail: krnet-unsubscribe@mailinglists.org > For additional commands, e-mail: > krnet-help@mailinglists.org > > See the KRNet archives at http://www.escribe.com/aviation/krnet/ > . > AOL and Compuserve do NOT pass KRNet email, so use some > other system! >