---------------------------------------------------------- Kolb-List Digest Archive --- Total Messages Posted Mon 02/03/03: 17 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:01 AM - Re: Stupid Question! (kuffel) 2. 07:06 AM - Re: Rotax 532 (johnjung@compusenior.com) 3. 07:31 AM - Re: Stupid Question! (jerb) 4. 07:42 AM - Re: Rotax 532 (Richard Pike) 5. 07:56 AM - Re: Stupid Question! (Richard Pike) 6. 08:13 AM - 447 won't start (H MITCHELL) 7. 09:07 AM - Re:Aluminum covering...?? (dixieshack@webtv.net (Mike and Dixie Shackelford)) 8. 09:59 AM - Re: Ultralight Pilot Busted (Jim and Phyllis Hefner) 9. 10:04 AM - Re: 447 not starting and tach trouble. (NealMcCann@aol.com) 10. 11:52 AM - Re: Re:Aluminum covering...?? message of Sun, 2 Feb 2003 23:56: (H MITCHELL) 11. 12:27 PM - Re: Aerobatics in a Kolb (Christopher Armstrong) 12. 01:37 PM - Re: Rotax 532 (Jim) 13. 04:27 PM - reply (Paul Petty) 14. 06:33 PM - crankcase clearing (GeoR38@aol.com) 15. 08:10 PM - Re: Follow up on the Pala Verda Incident (Jim and Phyllis Hefner) 16. 08:24 PM - Re: Re:Aluminum covering...?? message of Sun, (jerb) 17. 10:47 PM - Re: Rotax 532 (kuffel) ________________________________ Message 1 _____________________________________ Time: 12:01:27 AM PST US From: kuffel Subject: Re: Kolb-List: Stupid Question! --> Kolb-List message posted by: kuffel Paul Petty: <> Not a stupid question at all and worth archiving. 1) You are dramatically changing the load paths of the structure. In other words, there is a high probability you could be making the airplane less strong. The metal skin transfers stresses in ways not intended or tested by the designer. These loads can wind up being focused at a particular point instead of being distributed, causing a failure which otherwise would not occur. This is not likely to be a problem for metal skin attached to the fuselage cage of a Kolb because of its high design strength mandated by other factors. 2) There is some data which imply the scalloping of the fabric at the leading edge of the wing improves the airflow over the wing at high angles of attack. 3) I very much doubt you could detect any speed improvement by replacing the fabric with metal skin of the same shape. The Kolb configuration is inherently so high drag that any improvement in skin friction, even if it did exist, would reduce total drag by only a percent or two at most. 4) Perhaps obvious, but weight really is a major downside to consider. It would be like lugging around 10 gallons of unusable fuel, an intolerable inefficiency for most light airplane drivers. Hope this helps you avoid straying too far from the plans. Tom Kuffel Whitefish, MT Building (a modified) Original FireStar ________________________________ Message 2 _____________________________________ Time: 07:06:46 AM PST US From: "johnjung@compusenior.com" Subject: Re: Kolb-List: Rotax 532 --> Kolb-List message posted by: "johnjung@compusenior.com" Jim, Did you move the probes in the exhaust or just change the wires? Whichever you did, now do the other. Then get new readings, and report back. All you know now is that either the gage(s) or the porbe(s) or both are wrong. If they were all consistant, the reading would have switched. John Jung --> Kolb-List message posted by: "Jim" > Richard, Thanks for the info. Today I switched the probes and now both are reading about 1000. But I don't understand that! If the probe or gauge was wrong, wouldn't the readings be the same as before I switched except for being opposite to what it was before switching? Jim ________________________________ Message 3 _____________________________________ Time: 07:31:11 AM PST US From: jerb Subject: Re: Kolb-List: Stupid Question! --> Kolb-List message posted by: jerb At 01:00 AM 2/3/03 -0700, you wrote: >--> Kolb-List message posted by: kuffel > > >snip... >4) Perhaps obvious, but weight really is a major downside to consider. >It would be like lugging around 10 gallons of unusable fuel, an >intolerable inefficiency for most light airplane drivers. > >Hope this helps you avoid straying too far from the plans. > >Tom Kuffel >Whitefish, MT >Building (a modified) Original FireStar > >snip.... The extra weight is a very good point. Build it light, they fly better that way. What's the reason (desire) behind wanting to cover it with aluminum or does it need recover and if so are you trying to avoid the covering process. It's not that bad once you get the hang of it and start to understand what your doing. Get some one with a little covering experience to come help you get started. Wouldn't be surprised many Kolber's probably be willing to come to your location for a weekend to get your started if you offered to put them up. As far as covering the tail components I don't think you really would have a problem doing it. You might need to add a rib or two so the aluminum will not oil can or drum. If it works it will eventually crack. I'm a metal wacker, built a RV6 tail kit and helped a friend do his wings and fuselage. Also got a ThunderGull in the garage under construction. The wing kit I got was part metal and fabric. I decided to go completely metal after discussing what mod's I would have to do with the factory. This is an interesting point - when you fully metalize the wing on it, you have to use thicker aluminum on the center section top and bottom due to the extra loading the weight adds. So things do change. My recommendation, build it to the plans, its a proven airplane in that configuration. My self I like the fabric, it's easier to repair dings should you have to do so. jerb ________________________________ Message 4 _____________________________________ Time: 07:42:11 AM PST US From: Richard Pike Subject: Re: Kolb-List: Rotax 532 --> Kolb-List message posted by: Richard Pike John is correct in his analysis, but there may yet be another variable - what if the two cylinders are running at different temps? (And that is certainly not unusual) What do your spark plugs look like? Similar? Any chance you can borrow a gauge and probe known to be relatively accurate from a friend and get a "second opinion?" Richard Pike MKIII N420P (420ldPoops) At 08:05 AM 2/3/03 -0700, you wrote: >--> Kolb-List message posted by: "johnjung@compusenior.com" > > >Jim, > >Did you move the probes in the exhaust or just change the wires? >Whichever you did, now do the other. Then get new readings, and report back. > >All you know now is that either the gage(s) or the porbe(s) or both are wrong. >If they were all consistant, the reading would have switched. > >John Jung > > --> Kolb-List message posted by: "Jim" > > > Richard, > > Thanks for the info. Today I switched the probes and now both are > reading > about 1000. But I don't understand that! If the probe or gauge was > wrong, > wouldn't the readings be the same as before I switched except for being > opposite to what it was before switching? > > Jim > > ________________________________ Message 5 _____________________________________ Time: 07:56:47 AM PST US From: Richard Pike Subject: Re: Kolb-List: Stupid Question! --> Kolb-List message posted by: Richard Pike Many years ago, I read somewhere that the best thing you can do in constructing any airplane is to "Simplicate and add lightness." You make the call. Richard Pike MKIII N420P (420ldPoops) Do Not Archive At 10:19 PM 2/2/03 -0700, you wrote: >--> Kolb-List message posted by: "CaptainRon" > >I have been thinking of doing just that. Of late the only thing I'll redo is >the horizontal stabs in .017 alum. It looks like way too much+ work to do >the whole airplane. My best swag that if you do everything, you will gain >about 55 lbr in additional weight. It maybe 5-10kt faster. Might as well >just buy a Titan. :-) >I don't think it would be worth it. It may?? just be easier to wrap it in >fiberglass. > >do not archive >================================, > > > > Stupid Question I know, > > But hey I'm redneck! > > With the obvious factor being weight, what would be the down side of >constructing a Kolb's exterior in aluminum vs. poly fab?..... > > > > Please....DO NOT ARCHIVE :-) > > > > pp..... > > > > > > ________________________________ Message 6 _____________________________________ Time: 08:13:30 AM PST US From: "H MITCHELL" Subject: Kolb-List: 447 won't start --> Kolb-List message posted by: "H MITCHELL" After Gene Ledbetter could not get his started last weekend he insisted that I fly on without him because it was such a perfect day. My engine was running great. I landed at a friend's pasture, turned the plane around and visited for about 30 minutes. When I was ready to go home mine would not start. I tried everything but ended up getting a ride back to Panacea, hooking my trailer up and hauling the plane home G-r-r-r. It is not fuel mix. We bought our fuel at different times at different stations. I rebuilt my carb but she still would not start. The plugs were on the black side but not wet. I built a nifty little tool for viewing the spark and found that there was no spark at the plugs. My meter measured 170 ohms to ground through the pick-up coil. The Stratman sheet says it should be 60. Gene Ledbetter's coil to ground measurement read "open". Confirmed with a second meter. It is weird that we both have starting problems at the same time. Maybe it was an EMP from Tyndal AFB experiments when we flew in that direction?... Naw :( When I placed the order for replacement coils I knew the price would be outrageous but was astonished to find that the price had gone from the former $60 to an incredible $92. It seems that Rotax had also upgraded to a new part number so the old $60 ones were not all that good. Rotax must be buying from one of the U.S. government's man-rated suppliers. The worth-their-weight-in-gold coils will be delivered today and on the planes this PM. Stay tuned for further developments. Maybe I have bee watching too many news programs :) ________________________________ Message 7 _____________________________________ Time: 09:07:50 AM PST US From: dixieshack@webtv.net (Mike and Dixie Shackelford) Subject: Kolb-List: Re:Aluminum covering...?? message of Sun, 2 Feb 2003 23:56:09 -0800 --> Kolb-List message posted by: dixieshack@webtv.net (Mike and Dixie Shackelford) How about all those extra drilled holes in the airframe required to rivet the aluminum in place? Looks like you'd end up with a weaker and heavier structure.... Then, remember sometime back about the question of removing Homer's "scallops" from the airfoil......? Don't remember much about it but didn't a smooth surface devoid of those scallops between the ribs detract from performance? Maybe I'm missing the point? Mike in WV ________________________________ Message 8 _____________________________________ Time: 09:59:02 AM PST US From: "Jim and Phyllis Hefner" Subject: Kolb-List: Re: Ultralight Pilot Busted --> Kolb-List message posted by: "Jim and Phyllis Hefner" John Hauck wrote: Adriel flies a very old Kolb Twinstar, unless he changed plane recently. John/Kolbers: Adriel is still flying the Twinstar, which he highly modified the front cage for unobstructed photography. He is "hanging out" in the breeze, with a fiberglass pod on the right side, which holds his camera gear. The last time I saw his plane a year or so ago it still had the 503 on it, but have heard recently that he upgraded to a 912. He flew over my house a few months ago and did a 360 overhead and I was amazed at how quiet his engine was... thought he had installed an intake silencer or a different muffler.... I now know it was the 912 that made the difference. He only lives a few miles from me, but is rarely there for long in between shooting trips. Jim Hefner FF#022 Tucson, AZ ________________________________ Message 9 _____________________________________ Time: 10:04:03 AM PST US From: NealMcCann@aol.com Subject: Re: Kolb-List: 447 not starting and tach trouble. --> Kolb-List message posted by: NealMcCann@aol.com Don't know if this could help in this situation but once I had a tach problem and voltage regulator problem at the same time. My engines ground is straped to the airframe. I remember my regulator case wasn't grounded to the airframe. Even though the black wire on the regulator was always connected, the case itself wasn't. When I properly grounded the case of the regulator, everything got fixed right up. ________________________________ Message 10 ____________________________________ Time: 11:52:03 AM PST US From: "H MITCHELL" Subject: Re: Kolb-List: Re:Aluminum covering...?? message of Sun, 2 Feb 2003 23:56: --> Kolb-List message posted by: "H MITCHELL" Mike et al, A Mk3X builder in panacea Florida has covered his fuselage with aluminum. When he proposed this change I advised him not to drill any holes the framework. The next time I saw the plane he had drilled holes only to mount some Al. angles which he used to attach the skin. It came out surprisingly well and held up during his first (hard) landing. He even did a pretty clean job of making the seams smooth in the compound curve areas. It added some weight but met his own personal preference and looks good. Duane the plane,Tallahassee FL ----- Original Message ----- From: dixieshack@webtv.net Subject: Kolb-List: Re:Aluminum covering...?? message of Sun, 2 Feb 2003 23:56:09 -0800 --> Kolb-List message posted by: dixieshack@webtv.net (Mike and Dixie Shackelford) How about all those extra drilled holes in the airframe required to rivet the aluminum in place? Looks like you'd end up with a weaker and heavier structure.... Then, remember sometime back about the question of removing Homer's "scallops" from the airfoil......? Don't remember much about it but didn't a smooth surface devoid of those scallops between the ribs detract from performance? Maybe I'm missing the point? Mike in WV ________________________________ Message 11 ____________________________________ Time: 12:27:38 PM PST US From: "Christopher Armstrong" Subject: RE: Kolb-List: Aerobatics in a Kolb --> Kolb-List message posted by: "Christopher Armstrong" Anytime I have ever seen a film or a picture of a Kolb doing aerobatics it has been an Ultrastar, is the design of the Ultrastar balanced for aerobatics better than the other Kolbs? I think that was the only Kolb that existed back when people were uncareful enough to do this suicidal stuff. Now that we are mostly knowledgable enough to know that the planes will break if you do aerobatics in them we dont. The kolbs lift strut is not nearly as strong in compresion as in tension. so negative g maneuvers would be extremely hazardous, so I don't think anybody should worry about a negative g fuel supply! that said the u;trastar was about as strong as a firestar and weighed less, so it would have better g capability, so would be a "better choice" for this foolishness. topher ________________________________ Message 12 ____________________________________ Time: 01:37:43 PM PST US From: "Jim" Subject: Re: Kolb-List: Rotax 532 --> Kolb-List message posted by: "Jim" Richard and John, Thanks for the comments. I will try some of your suggestions next time I am able. Jim ----- Original Message ----- From: "Richard Pike" Subject: Re: Kolb-List: Rotax 532 > --> Kolb-List message posted by: Richard Pike > > John is correct in his analysis, but there may yet be another variable - > what if the two cylinders are running at different temps? (And that is > certainly not unusual) > > What do your spark plugs look like? Similar? > Any chance you can borrow a gauge and probe known to be relatively accurate > from a friend and get a "second opinion?" > > Richard Pike > MKIII N420P (420ldPoops) > > At 08:05 AM 2/3/03 -0700, you wrote: > > >--> Kolb-List message posted by: "johnjung@compusenior.com" > > > > > >Jim, > > > >Did you move the probes in the exhaust or just change the wires? > >Whichever you did, now do the other. Then get new readings, and report back. > > > >All you know now is that either the gage(s) or the porbe(s) or both are wrong. > >If they were all consistant, the reading would have switched. > > > >John Jung > > > > --> Kolb-List message posted by: "Jim" > > > > > > Richard, > > > > Thanks for the info. Today I switched the probes and now both are > > reading > > about 1000. But I don't understand that! If the probe or gauge was > > wrong, > > wouldn't the readings be the same as before I switched except for being > > opposite to what it was before switching? > > > > Jim > > > > > > ________________________________ Message 13 ____________________________________ Time: 04:27:04 PM PST US From: "Paul Petty" Subject: Kolb-List: reply SPAM_PHRASE_00_01, USER_AGENT_OE, USER_IN_WHITELIST) --> Kolb-List message posted by: "Paul Petty" Kolber's Thanks for the info. I had no intensions of covering my project in aluminum. Was just curious after looking at a titan. And as always just trying to learn.I'm a tinker nut. Love to tinker around especially with engines. Airplanes however I plan to leave as designed. Speaking of witch I noticed that when the 2 cycle family has problems or wont start, first thing most of you check first is electrical. Have also noticed that fuel loading has never been mentioned. Very common problem with 2 stokes especially when one is shut down and shortly restarted. Not familiar with the ones used on aircraft, but not being able to clutch the thing and rev it to the threshold of pain to blow it out so to speak would seem to cause the crankcase to "load up" with fuel. Just an idea.... pp... do not archive ________________________________ Message 14 ____________________________________ Time: 06:33:01 PM PST US From: GeoR38@aol.com Subject: Kolb-List: crankcase clearing --> Kolb-List message posted by: GeoR38@aol.com In a message dated 2/3/03 7:27:47 PM Eastern Standard Time, ppetty@c-gate.net writes: > . Not familiar with the ones used on aircraft, but not being able to clutch > the thing and rev it to the threshold of pain to blow it out so to speak > would seem to cause the crankcase to "load up" with fuel. Just an idea.... > > pp... > > do not archive > > Makes sense to me, Paul, and I DON't fart around with engines, just planes. But not ones that I plop ol watash into. .... just models. Are you speaking of the centrifugal clutches that I have seen on some Quicksilvers?...or just the idea of a clutch to enable "clearing" the crankcase? George Randolph ps, the crankcase flooding almost deep sixed me over my son about 15 years ago as I was showing off over the front yard he was playing in ________________________________ Message 15 ____________________________________ Time: 08:10:12 PM PST US From: "Jim and Phyllis Hefner" Subject: Kolb-List: Re: Follow up on the Pala Verda Incident --> Kolb-List message posted by: "Jim and Phyllis Hefner" Subject: Follow up on the Pala Verda Incident From: VIC (vicw@vcn.com) Date: Sat Feb 01 - 7:25 PM -- Kolb-List message posted by: "VIC" vicw@vcn.com I am not passing judgment on Mr. Heaney because I don't have all the details but we can learn from this situation by making sure everyone is in the loop when we fly around sensitive areas. I am sure Mr. Heisey would not want to repeat his encounter with the Maricopa County Sheriff Department (they feed you green bologna and moldy bread in the jail), the NRC, or the FBI. Vic/Kolbers: I totally agree, we can all learn fromAdriel's misadventure andcommunications with Flight Services is alwaysa good place to start, after reviewing the sectional, if there is anything unusual concerning restrictions. When I recently flew down to the Libbey Army base airport at Sierra Vista, the charts show thatwhole area as restricted, but Capt Ron told me that was only during the week. Even on the weekend, I called the tower 30miles out to make sure they knew I was an ultralight inbound for SV airport, checked on status of airspace and runway usage. The tower was extremely helpful getting me in and out because they knew I was coming long before I arrived. Adriel had told the Luke tower he was there and generally what his purpose was, but obviously didn't have enough specific discussion about where he would be flying in relation tothe PowerPlant. He was shooting some old trails that lead into the nearby foothills, away from the pwr plant and these miscommunicationsled to the incident. I'm sure Adriel does not wish to repeat his unexpected encounters that day. In his line of work, this is probably not the first time and won't be the last time for going near restricted areas, but next time I'm sure there will be a lot more discussion of the specifics of his intentions with the FS's or tower to make sure it doesn't happen again. Adriel's plane is a licensed N-number and he a licensed pilot, with lots of GA experience flying Navajo tribal leaders around the SW many years prior to his freelance photography, flying the Twinstar. This shows something like thiscan happen to anyone, no matter what your experience, and is a good lesson as you said Vic. My original post was in response to a post that made him out to be a senseless moron that shouldn't be allowed to fly a kite.... far from the reality of the situation! Thanks, Jim Hefner FF#022 Tucson, AZ ________________________________ Message 16 ____________________________________ Time: 08:24:10 PM PST US From: jerb Subject: Re: Kolb-List: Re:Aluminum covering...?? message of Sun, 2 Feb 2003 23:56: --> Kolb-List message posted by: jerb Actually as long as he didn't get carried away, used normal rivet spacing for aircraft sheet metal fabrication, it would probably strengthen the cage. I know when it can to assembling my Gull wing, the ribs were .016 aluminum and pretty flimsy. After drilling the skin and clecoing it to the ribs, it formed a very solid box assembly. Much stronger than you ever would have thought it would have been. jerb Do not archive ________________________________ Message 17 ____________________________________ Time: 10:47:01 PM PST US From: kuffel Subject: Re: Kolb-List: Rotax 532 --> Kolb-List message posted by: kuffel Jim: <> John Jung: <> Richard Pike: <> There is yet another possibility. The difficulty may be in the wiring not the engine, guage or probe. Our thermocoupler probes put out a very low voltage at a very low current. This means even a very small increase in the resistance of any connection in the circuit can have a major impact on the temperature reading. In the course of changing, Jim might have "cleaned" the problem contact simply by manipulating the wires. If this was the original problem then he should expect normal guage performance until the contact again gets dirty, oxidized, etc. Tom Kuffel Whitefish, MT Building Original FireStar