---------------------------------------------------------- Kolb-List Digest Archive --- Total Messages Posted Fri 04/06/07: 15 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 03:25 AM - Re: Re: Monument Valley 2007 (pat ladd) 2. 03:37 AM - Re: Kolb Wing Attach Points (pat ladd) 3. 05:10 AM - Re: Kolb Wing Attach Points (Eugene Zimmerman) 4. 05:42 AM - Re: Kolb Wing Attach Points (FS2Kolb@aol.com) 5. 06:14 AM - Re: Kolb Wing Attach Points (Vic Peters) 6. 06:29 AM - Re: Re: Monument Valley 2007 (TheWanderingWench) 7. 06:37 AM - Fw: gummint (robert bean) 8. 07:32 AM - Service bulletins (Jimmy) 9. 09:18 AM - Re: Service bulletins (Thom Riddle) 10. 10:11 AM - Re: Re: Monument Valley 2007 (Bob Noyer) 11. 10:43 AM - Re: Kolb Wing Attach Points (Bob Noyer) 12. 01:09 PM - Re: Kolb Wing Attach Points (David Lehman) 13. 01:16 PM - Ground Idea (Paul Petty) 14. 07:30 PM - Re: Kolb Wing Attach Points (Dana Hague) 15. 08:35 PM - Re: Kolb Wing Attach Points (JetPilot) ________________________________ Message 1 _____________________________________ Time: 03:25:41 AM PST US From: "pat ladd" Subject: Re: Kolb-List: Re: Monument Valley 2007 All you need is a hefty appetite an Iron stomach and a steady hand. BYOC >> Hi Craig, sounds too good to miss. BYOC ???? Bring your own ... Coffee? Coca Cola? Cheese? Chips? Chairs? Chameleon? Coronet? Cornet? Cordwainer? Cheers Pat do not archive ________________________________ Message 2 _____________________________________ Time: 03:37:08 AM PST US From: "pat ladd" Subject: Re: Kolb-List: Kolb Wing Attach Points What it takes to bend that pin at a one inch spread,........ on a heavy MK III. >> Hi Michael, I can give you something to work on. If you accelerate a Mark111 with a Jabiru engine full throttle over about 50 yards from a standing start and hit a vertical RSJ with the port wing just outside the lift strut attachment point it will bend the front attachment pin approc 3/16 of an inch. It will also distort the cockpit cage. Dont ask... Cheers Pat do not archive ________________________________ Message 3 _____________________________________ Time: 05:10:33 AM PST US From: Eugene Zimmerman Subject: Re: Kolb-List: Kolb Wing Attach Points OUCH ! THAT HURT ! On Apr 6, 2007, at 6:36 AM, pat ladd wrote: > If you accelerate a Mark111 with a Jabiru engine full throttle over > about 50 yards from a standing start and hit a vertical RSJ with > the port wing just outside the lift strut attachment point it will > bend the front attachment pin approc 3/16 of an inch. It will also > distort the cockpit cage. ________________________________ Message 4 _____________________________________ Time: 05:42:57 AM PST US From: FS2Kolb@aol.com Subject: Re: Kolb-List: Kolb Wing Attach Points Whats an RSJ? In a message dated 4/6/2007 4:37:38 A.M. Mountain Daylight Time, pj.ladd@btinternet.com writes: If you accelerate a Mark111 with a Jabiru engine full throttle over about 50 yards from a standing start and hit a vertical RSJ with the port wing just outside the lift strut attachment point it will bend the front attachment pin approc 3/16 of an inch. It will also distort the cockpit cage. Dont ask... Cheers Pat do not archive ************************************** See what's free at http://www.aol.com. ________________________________ Message 5 _____________________________________ Time: 06:14:00 AM PST US From: "Vic Peters" Subject: Re: Kolb-List: Kolb Wing Attach Points Whats an RSJ? Recreational sport Jaguar do not archive Vic ________________________________ Message 6 _____________________________________ Time: 06:29:39 AM PST US From: TheWanderingWench Subject: Re: Kolb-List: Re: Monument Valley 2007 Pat - I can't believe you left out the most important "C" word - it's chocolate, of course! Arty DO NOT ARCHIVE --- pat ladd wrote: > > > All you need is a hefty appetite an Iron stomach and > a steady hand. BYOC > >> > > Hi Craig, > > sounds too good to miss. BYOC ???? > > Bring your own ... > Coffee? > Coca Cola? > Cheese? > Chips? > Chairs? > Chameleon? > Coronet? > Cornet? > Cordwainer? > > Cheers > > Pat > > do not archive > > > > > > browse > Subscriptions page, > FAQ, > http://www.matronics.com/Navigator?Kolb-List > > Web Forums! > > > > > www.LessonsFromTheEdge.com "Life's a daring adventure or nothing" Helen Keller "I refuse to tip toe through life just to arrive safely at death." ________________________________ Message 7 _____________________________________ Time: 06:37:12 AM PST US From: robert bean Subject: Kolb-List: Fwd: gummint Listers, the following is a note I sent to Thom Riddle. -Too lazy to retype it. Just wondering if any of you got the same request and your opinions. BB, still haven't wandered down to the workshop to visit my lonely MkIII > > Good morning Thom, Did you get the mailing from the FAA this past > winter to fill > out the online questionnaire? It consisted of what avionics you > have on board. > > I did, with some hesitation, fill it out. Laughable because I had > none of the listed > gadgets. My concern is with the user fee subject being tossed > around now. > > Back in the 70s I used to return a form to the feds stating how > many hours I had > flown my plane each year. -seemed harmless until one day I received > a bill from > the IRS for several back years of the "air use tax". I'm not > making this up. > Several hundred dollars including interest and penalty. This being > at a time when > I had a young family and money was tight. I had not a clue > beforehand that such a tax > existed and was especially galling in that the FAA provided me with > zero services. > -Still don't. > So I don't think I'm being paranoid on the subject, just suspicious. > BB ________________________________ Message 8 _____________________________________ Time: 07:32:31 AM PST US From: "Jimmy" Subject: Kolb-List: Service bulletins When I try to access the Rotax service bulletins from the listings of service bulletins I get a blank page. What am I doing wrong. I am signed in with my password. Jimmy Hankinson 912-863-7384 Firefly #035, (N6007L) JYL (Sylvania, Ga.) Pegasus Field (Home) 2000 Feet X 100 Feet- Grass Rocky Ford, Georgia Do Not Archive -- ________________________________ Message 9 _____________________________________ Time: 09:18:08 AM PST US Subject: Kolb-List: Re: Service bulletins From: "Thom Riddle" Jimmy, Are you using this link page? http://www.rotax-owner.com/ If so, try using the guest login instead of your user name and password, in case there is a problem with authenticating your login data. do not archive -------- Thom in Buffalo Have you noticed since everyone has a camcorder these days no one talks about seeing UFOs like they used to? Read this topic online here: http://forums.matronics.com/viewtopic.php?p=105330#105330 ________________________________ Message 10 ____________________________________ Time: 10:11:22 AM PST US From: Bob Noyer Subject: Re: Kolb-List: Re: Monument Valley 2007 Gnaw, not choclit, it's (bi)Carbonate! regards, Bob N. FireFly 070 Old Kolb http://www.angelfire.com/rpg/ronoy/ do not archve ________________________________ Message 11 ____________________________________ Time: 10:43:29 AM PST US From: Bob Noyer Subject: Re: Kolb-List: Kolb Wing Attach Points RSJ= Real Stout Joist regards, Bob N. FireFly 070 Old Kolb http://www.angelfire.com/rpg/ronoy/ do not archive ________________________________ Message 12 ____________________________________ Time: 01:09:14 PM PST US From: "David Lehman" Subject: Re: Kolb-List: Kolb Wing Attach Points Mike... Take a look at what holds the Luscombe (heavier than a Cub) wing spar to the fuselage carry-through... An aluminum pin, drilled at both ends and held in place with cotter pins... DVD do not archive On 4/5/07, JetPilot wrote: > > > The two pins on each end of the wing strut have the most force on them > then the pins in the center section, but not a huge amont... The two strut > pins have something like 25 % more force on them than the pin that attaches > to the wing center section. But the huge bending moment caused by that > large 1 inch gap makes that one the one that will fail first... What it > takes to bend that pin at a one inch spread, I cannot find a spec on that > anywhere. I would be ok with this on a FireStar, or FireFly, but not on a > heavy MK III. Have you ever seen how thick the wing attach bolts are on a > J-3 Cub, they are about twice the streingth of what the MK III is for the > same weight class plane. > > To help this, I have gone to NAS hardware which is about 20 % stronger > than AN hardware, and I am using a bolt and nut, so that if it does bend, > one end will not pull out. I will be drilling that out and going to a > bigger diameter bolt there just to be sure. I would also like to drill out > and go one size bigger bolts on the strut ends, but it it might remove to > much material from the ends and cause weakness in the 4130 metal of the wing > strut end, so I will not. These have much less bending moment, so are not > as likely to fail as the center section as can be seen in the pictures > below. Larry had a good idea of putting a spacer in the lower attach point > pin to keep the stress to one side of it. That will put almost all the > stress on one side of the fitting, but will keep that bolt stressed in sheer > instead of bending force. I will use a bunch of washers to do this. I > will also be careful to make sure I do not put to many in so that it does > not cause this fitting! > to be tight. Making this tight instead of free floating could cause > fatigue on the strut end and cause a fialure over time. Remember the tail > that fatigued fialed when its foward fitting was not allowed to float free ? > > Attached are pictures so you all can see what I am talking about, and if > any one has any more ideas or sees something I dont by all means respond to > this thread. > > Michael Bigelow > > -------- > "NO FEAR" - If you have no fear you did not go as fast as you could have > !!! > > ________________________________ Message 13 ____________________________________ Time: 01:16:39 PM PST US Subject: Kolb-List: Ground Idea From: "Paul Petty" Hey guys, I came up with this idea for a good ground attach point for the ground cable to airframe point. Its a GM side post extention that is made for external amps in cars and I think it will work better than just bolting the cable end to the airframe. It is made out of brass and with dieletric compound should make a nice solid connection. If any want the part number let me know. They are available at any NAPA store. Also there is a "thinner" 3/8" nut for the back side of it that can be found on a GM starter. It leaves the "2 threads" extruded that the DAR's like. Someone may can come up with an AN nut. I just robbed a starter and used the star shaped locking washer. [Wink] -------- Paul Petty Kolbra #12 Ms Dixie Final assembly! Read this topic online here: http://forums.matronics.com/viewtopic.php?p=105359#105359 Attachments: http://forums.matronics.com//files/p4050038_118.jpg http://forums.matronics.com//files/p4050039_163.jpg ________________________________ Message 14 ____________________________________ Time: 07:30:04 PM PST US From: Dana Hague Subject: Re: Kolb-List: Kolb Wing Attach Points At 08:06 PM 4/5/2007, JetPilot wrote: > >The two pins on each end of the wing strut have the most force on them >then the pins in the center section, but not a huge amont... The two strut >pins have something like 25 % more force on them than the pin that >attaches to the wing center section. But the huge bending moment caused >by that large 1 inch gap makes that one the one that will fail >first... What it takes to bend that pin at a one inch spread, I cannot >find a spec on that anywhere.... >To help this, I have gone to NAS hardware which is about 20 % stronger >than AN hardware... I've been kinda wondering about that too, so I looked at the numbers. On my Ultrastar, the wing attachment with the 1" gap is in the rear, using a 1/4" diameter clevis pin. That pin is rated at 7360# double shear, which would seem to be no problem... but it's not really loaded in shear. Bending is indeed another matter. Figuring the bending loads on that pin very roughly, if the fitting is exactly in the center and is 1/8" thick, the clevis pin will hold 877# (with no safety factor). If you can space it all the way to one side, then the single shear strength of 3680# would be in effect... but on the Ultrastar you can't control where it ends up. However, on the US this attachment sees only drag loads so it's probably OK... though there would be added loads due to aileron deflection. Does make me wonder if there was ever a published maneuvering speed for this plane, though... If the gap at a fitting is less than 1", the bending stresses on the pin go down proportionately. A 5/16" pin is 1.56X as strong in shear and 2.44X as strong in bending; a 3/8" pin is 2.25X and 5.06X, respectively. Good design practice dictates that a fitting be designed so that it can be drilled out for the next larger size fastener if necessary (in case of wear), but not necessarily the next size over that. On the lift strut and inboard wing attachment at the main spar, the wing strut takes the bulk of the vertical load (exactly all the vertical load if it attaches exactly at the midpoint of the wing panel). However, the tension in the lift strut is twice the vertical load (assuming a strut angle of 30, which is about right), thus the tension in a lift strut is approximately equal to the airplane's weight plus any tail downforce. I don't know how much gap there is on the later models' strut attachment but on the US it's a pretty close fit. On the forward wing root attachment, there's little or no vertical load, but it has to oppose the inward force from the lift strut, which is the strut tension times cos(30) or 87% of the plane's weight... so that's the force on that pin or bolt. Of course, none of the above takes into account flight load factors or required safety factors. I don't know the specs of the NAS hardware you're using, but I'm not sure I like that idea... I hate to second guess the designer, especially on a proven design, and a stronger bolt will be more brittle... fatigue may become an issue, especially if the bolt gets worn or nicked. Eeek, too much thinking for a Friday night... :) -Dana -- -- The citizens of the United States are getting the government they deserve. The problem is that I'm also getting the government they deserve. ________________________________ Message 15 ____________________________________ Time: 08:35:46 PM PST US Subject: Kolb-List: Re: Kolb Wing Attach Points From: "JetPilot" Hi Dana, That is a very good analisys of the loads on the pins, where did you get the figures for bending the pins across 1 inch ? According to your figures, the pin is only 1/10 th as strong when the load is bending instead of sheer, which seems about right. There is very little force on the trailing edge attachment of a Kolb, I would not worry at all about that. My MK III weighs almost 3 times what the Ultrastar and the Firefly do, but uses the same size pins... What is not an issue on some planes could be on others. The one thing I think you got wrong is the stress on that center pin that I am talking about. It is more than the weight of the airplane. With the struts at 45 degrees it would be the the same as the aircraft weight, having the strut go out at a 60 degree angle from vertical makes it 1.7 times the weight of the plane, or 1700 pounds at 1 G on my MK III. The spar is being forced inwards by the struts at a 60 degree angle from the load, I think you just used the wrong part of the triangle. NAS 6600 hardware is used as aircraft structrual bolts, and is used in many airplanes for very high stress wing spar attachment ( Low wing planes with no struts ). This type of bolt was recommended to me by an airline structrual inspector. I searched the applications and confirmed this to be true before switching bolts. To put the next size bigger pin in, I will have to be careful to drill the holes larger only inwards, taking care not to make the holes any closer to the edges, but there is plenty of material to do this. See the attached picture. -------- "NO FEAR" - If you have no fear you did not go as fast as you could have !!! Read this topic online here: http://forums.matronics.com/viewtopic.php?p=105403#105403 Attachments: http://forums.matronics.com//files/ultralightmikekolbdetail01_08_2007_11_416.jpg ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message kolb-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Kolb-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/kolb-list Browse Digests http://www.matronics.com/digest/kolb-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.