Date: Thu, 11 Jan 1996 06:10:12 -0500 From: CCady@aol.com Subject: Roncz Canard Responding to an earlier series of posts concerning the elevators being mounted low. I recently test flew my project with this condition and despite the lower than usual elevators it feels ok and there appear to be no problems. When I mounted the elevators I was trying to get the trailing edge up travel. It seems that you don't use much trailing edge up or down elevator unless you really push the nose over. It appears that the canard works ok built this way. Date: Thu, 11 Jan 1996 21:57:35 -0500 (EST) From: Bill Walsh Subject: Re: Roncz Canard In observation of the below note. I had that concern about elevator travel and had Nat lookat it when he was here....he said it was more that adaquate. Iknowhe seems to really stress that point in the plans (proper travel). my 2 bits BW On Thu, 11 Jan 1996 CCady@aol.com wrote: > Responding to an earlier series of posts concerning the elevators being > mounted > low. I recently test flew my project with this condition and despite the > lower than > usual elevators it feels ok and there appear to be no problems. When I > mounted the > elevators I was trying to get the trailing edge up travel. It seems that you > don't use > much trailing edge up or down elevator unless you really push the nose over. > > > It appears that the canard works ok built this way. > Subject: Re: Roncz Canard Date: Fri, 12 Jan 1996 09:12:09 -0500 (EST) From: "Randy Smith" When I read this I got to thinking... (TAKE COVER!) I seem to remember that the wingtip votex generated by the canard is used to increase the laminar flow on the outboard section of the main wing. One can think of it as a vortex generator for the main wing, its just part of the canard configuration benefit. If this is correct, then isn't the placement of the canard in relation to the main wing important to the extent that the vortex is beneficial? Too low or too high, you lose the benefit of the vortex. I may very well be all wet. > Responding to an earlier series of posts concerning the elevators being > mounted > low. I recently test flew my project with this condition and despite the > lower than > usual elevators it feels ok and there appear to be no problems. When I > mounted the > elevators I was trying to get the trailing edge up travel. It seems that you > don't use > much trailing edge up or down elevator unless you really push the nose over. > > > It appears that the canard works ok built this way. --* --- -* **-* *-** -*-- -* Crash Rescue Team 7 - Don't PANIC! Cozy Mk. IV AT&T General Purpose Computing Randy.Smith@ColumbiaSC.attgis.com |---( )---| Global Support Center Voice 803-939-7648, V+ 633-7648 ___o/o\o___ West Columbia, SC 29170 "I am the way, the truth, and the life..." -JC From: Marc J. Zeitlin Subject: Roncz Canard (fwd) Date: Fri, 12 Jan 96 9:33:19 EST Cliff Cady wrote: >Responding to an earlier series of posts concerning the elevators being >mounted low. I recently test flew my project with this condition....... Hey! Congratulations!!!! Another E-racer flying! >......... and >despite the lower than usual elevators it feels ok and there appear to >be no problems. Well, this is certainly good news. After Philip Johnson visited, I took my canard out and measured everything against the templates again, and found that things were not quite as bad as I originally thought, dimensionally. That, along with John Roncz's response to fly it and see how it goes, was leading me toward doing just that. I think that this input clinches it. >It appears that the canard works ok built this way. Thanks a bunch for the input - glad everything works. Give us a rundown of the airplane and the first few flights!! -- Marc J. Zeitlin Email: marcz@an.hp.com From: Marc J. Zeitlin Subject: Re: Roncz Canard (fwd) Date: Fri, 12 Jan 96 15:02:34 EST Randy Smith wrote: >I seem to remember that the wingtip votex generated by the canard is used >to increase the laminar flow on the outboard section of the main wing. >One can think of it as a vortex generator for the main wing, its just part >of the canard configuration benefit. I think you are incorrect here. My understanding is that the canard vortex is used to affect the effective Angle of Attack (AOA) of the main wing. The main wing is NOT a "laminar flow airfoil", unlike the canard. Vortex generators actually do exactly the opposite of creating (or ensuring) laminar flow - they ensure a TURBULENT boundary layer, but one which will stay attached, which a laminar layer may not, at high AOA. So, the canard does affect the main wing, but NOT by helping any laminar flow effect on it, and the vortex generators do not have a laminar flow effect either. >If this is correct, then isn't the placement of the canard in relation >to the main wing important to the extent that the vortex is beneficial? The vortex IS beneficial, and the placement IS important. >Too low or too high, you lose the benefit of the vortex. This is true. However, the original problem statement (accessible on the web at): http://www-msy-me.wal.hp.com/~marcz/cozy_mkIV/chapters/chap11_2.html did not indicate a problem with canard placement, only a slight SHAPE difference. My canard is correctly positioned to within 1/32" vertically, and there is NO WAY the system is THAT sensitive :-). Also, I would venture a guess that even if the canard WERE 1/8" (or even 1/2" to 1") high or low, that STILL wouldn't be enough to substantially affect the canard vortex/main wing interaction. Think about how the canard/main wing angular relationship changes with speed and AOA changes - at low speeds and high AOA, the canard will be inches higher than it will be at high speeds and low AOA. Very small positional differences couldn't be that important. What I was worried about was the SHAPE issue on a laminar flow airfoil with a slotted flap (elevator). Since: 1) My slot is the right size 2) The canard trailing edge droop is about 1/16" (not the 1/8" indicated on the web page) 3) The elevator droop below the canard is on the bottom (high pressure) surface (so I don't have to worry about seperation) 3) John Roncz said to try it the way it is (and that there MAY be some stick force differences due to aerodynamic pressure on the exposed front edge of the elevator). 4) Cliff Cady says he's got a similar shape and it works fine on the E-racer I think I'm OK the way it is, and I'm going to leave it alone unless I find some problem during the first few flights (lo, these many years from know). >I may very well be all wet. Well, damp anyway :-). Thanks for thinking about it. If anyone can show me where I'm wrong with any of this, I'd be glad to hear it - but let's not hash over the old arguments (which are available for perusal at): http://www-msy-me.wal.hp.com/~marcz/cozy_mkIV/mail_list/topics_95/chap_11.txt Thanks again. -- Marc J. Zeitlin Email: marcz@an.hp.com Subject: Re: Roncz Canard (fwd) Date: Fri, 12 Jan 1996 16:19:23 -0500 (EST) From: "Randy Smith" Marc Zeitlin wrote: > > Randy Smith wrote: > > >I seem to remember that the wingtip votex generated by the canard is used > >to increase the laminar flow on the outboard section of the main wing. > >One can think of it as a vortex generator for the main wing, its just part > >of the canard configuration benefit. > > I think you are incorrect here. > > My understanding is that the canard vortex is used to affect the > effective Angle of Attack (AOA) of the main wing. The main wing is NOT > a "laminar flow airfoil", unlike the canard. Vortex generators actually > do exactly the opposite of creating (or ensuring) laminar flow - they > ensure a TURBULENT boundary layer, but one which will stay attached, > which a laminar layer may not, at high AOA. So, the canard does affect > the main wing, but NOT by helping any laminar flow effect on it, and the > vortex generators do not have a laminar flow effect either. For those of you scoring at home, that's 1/2 point for Randy remembering that there was SOME SORT of relationship between the vortex and the main wing. :-) > >If this is correct, then isn't the placement of the canard in relation > >to the main wing important to the extent that the vortex is beneficial? > > The vortex IS beneficial, and the placement IS important. > > >Too low or too high, you lose the benefit of the vortex. > > This is true. However, the original problem statement (accessible on > the web at): > > http://www-msy-me.wal.hp.com/~marcz/cozy_mkIV/chapters/chap11_2.html > > did not indicate a problem with canard placement, only a slight SHAPE > difference. My canard is correctly positioned to within 1/32" > vertically, and there is NO WAY the system is THAT sensitive :-). Also, > I would venture a guess that even if the canard WERE 1/8" (or even 1/2" > to 1") high or low, that STILL wouldn't be enough to substantially > affect the canard vortex/main wing interaction. I agree. As a matter of fact, I thought that perhaps you were speaking of shape and or incidence angle differences only microseconds after I sent my post. Once again Randy engaged his keyboard without understanding the question. > >I may very well be all wet. > > Well, damp anyway :-). Thanks for thinking about it. If anyone can Anyone got a towel? :-) Hey maybe I'll drip on the keyboard and sh*rt it(rr2$54%^ > Thanks again. > > -- > Marc J. Zeitlin Email: marcz@an.hp.com > --* --- -* **-* *-** -*-- -* Crash Rescue Team 7 - Don't PANIC! Cozy Mk. IV AT&T General Purpose Computing Randy.Smith@ColumbiaSC.attgis.com |---( )---| Global Support Center Voice 803-939-7648, V+ 633-7648 ___o/o\o___ West Columbia, SC 29170 "I am the way, the truth, and the life..." -JC Date: Sat, 20 Jan 1996 15:56:39 -0500 From: JQUESTCOZY@aol.com Subject: ch 13 nose question/elevator & canard also I know there was a lot of discussion on elevators in relation to the canard, When I was jigging my elevators to the canard, I lower'd my elevators approx. .100 in. in order to get the 0.2 min. gap between the top of the elevators and the trailing edge of the canard that Nat stressed in Fig 18. I discovered later also after the hinges were installed that this caused the bottom side of my elevators to be about .100 below the bottom of my canard when viewed after it was installed. I'm worried about a possible flutter, so I plan on adding some Uni the full length on top of the canard at the trailing edge and sanding down the bottom side and removing and installing new hinges per the jig block L. Are their many others that had a hard time getting the .200 min. gap between the elevator and the trailing edge of the canard when using Jig block L. From: Marc J. Zeitlin Subject: elevator and canard question Date: Sun, 21 Jan 96 23:54:57 EST John Wilemski wrote: > When I was jigging my elevators to the canard, I lower'd my elevators >approx. .100 in. ............ >...... the bottom side of my elevators to be about .100 below the bottom of >my canard when viewed after it was installed. I'm worried about a >possible flutter,......... >Are their many others that had a hard time getting the .200 min. gap between >the elevator and the trailing edge of the canard when using Jig block L. Interesting you should mention this. I had exactly the same problem, but not necessarily for the same reason(s). The whole history of this discussion (and information and recommendations I received from Nat, Vance Atkinson, and John Roncz!!, not to mention boatloads of mailing list members) is in the mailing list archives on the web pages at: http://www.ultranet.com/~marcz/cozy_mkIV/mail_list/ I think it's in the "Chapter 10" and/or "Chapter 11" sections in both "1995" and "Current Year". If you have any trouble accessing these, please let me know. P.S. - John (and others), please put a signature (or your name) somewhere in your message, so that we'll know who's asking the questions. Thanks. :-). -- Marc J. Zeitlin Email: marcz@an.hp.com From: "Volk, Ray" Subject: Chapter 10 Date: Wed, 20 Mar 96 11:03:00 PST Michael wrote- >Secondly I found that with all four AN3 bolts loose (the ones that >secure the two offsets), it was possible to get a significant >misalignment of the two elevators--in other words the combined slop of >the four bolts in their respective slightly oversize holes allowed the >two elevators to rotate out of alignment. I am concerned that just >tightening the bolts is the total answer and I am inclined to install >four dowel pins in addition (perhaps 1/8") that will be a press fit >rather than the slop existing in the bolt holes. Has anyone else also >experienced this and/or any recommendations?, Michael It has been awhile since I completed chapter 10, and I don't remember what the plans said about drill sizes etc., but I do remember that my bolts fit very tight into the offsets and elevator tubes, ie it was difficult to push them in the holes with your fingers. They needed a little persuasion both going in and when taken out. I believe your right in not liking any looseness in this area. I'm not that knowledgeable in the mechanical area but my first thoughts would be to try the next size larger bolt and if necessary fine tune it down a little. For what it's worth. Ray Volk rvolk@honeywell.space.com From: "Steve Campbell" Subject: COZY: Rivet Supplier Date: Tue, 6 Aug 1996 12:54:44 I am starting on Chapter 11 and several months ago ordered MSC-32 rivits from Wicks. Today they told me that not only are they out of stock, Cherry made a batch of rivits out of the wrong material, is remaking the batch, but won't ship until early October (Yikes!) Aircraft Spruce is also out of stock. Any other suggestions for where else I can get these things? Steve **************************************** Stephen A. Campbell Associate Professor, EE University of Minnesota ***************************************** From: "Dalrymple, Mark J" Subject: COZY: RIVETS Date: Tue, 06 Aug 96 12:30:00 PDT IN REGARDS TO RIVETS, I believe a shop called, Deering Engineering could help you. They stock all kinds Rivets and AN bolts and nuts. Also, any kind of aircraft repair station should also stock what you are looking for. I called Deering and they said they need more information on the part #. The MSC-32 part # was no good to them. If you fax them a Spruce Catalog page that references the part, I am sure they could match it. Deering is in Long Beach, Ca, (next to my work) and their ph# is 310-595-1168. Good luck Mark Dalrymple Deep in Wings Date: Tue, 15 Oct 1996 15:26:00 -0400 From: "William B." <74744.2301@compuserve.com> Subject: COZY: BSCQ-44 Pop Rivets I'm having the same problem as some have had previously in finding the countersunk pop rivets (BSCQ-44) for the NC-6 inserts. Wicks -- No Joy. A.S.S. East -- No Joy. Someone in the archives gave a number for a company called Deering Engineering, (301) 595-1168. I tried it and it is a wrong number. Where are you people finding these things? The difference between the "Q" rivets and the "N" rivets is that the "N" rivets do not retain the steel shaft throughtout the entire length of the rivet. I assume these are not used because they don't have the required shear strength. William E. Buckley (Cozy Mk IV, #437, Chap 10 & 11) 74744.2301@compuserve.com From: "Rob Cherney" Organization: Ellicott City, Maryland Date: Tue, 15 Oct 1996 15:52:01 -0400 Subject: Re: COZY: BSCQ-44 Pop Rivets > I'm having the same problem as some have had previously in finding the > countersunk pop rivets (BSCQ-44) for the NC-6 inserts. Wicks -- No Joy. > A.S.S. East -- No Joy. Someone in the archives gave a number for a company > called Deering Engineering, (301) 595-1168. I tried it and it is a wrong > number. Wrong area code. They are in the L.A. area -- (310). Rob- +--------------------------------------------------------+ |Robert Cherney Home Phone: (410)465-5598 | |Ellicott City, Maryland e-mail: cherney@clark.net | +--------------------------------------------------------+ Date: Tue, 17 Dec 1996 21:46:48 -0500 From: Jim Hocut Subject: COZY: Ch 11 - Canard/Elevator Revisited I'd like to thank Marc for putting the sketch of this problem on his web site so we can see what's going on here. If it hadn't been for the fact that Marc and others (including THE MAN John Roncz) had so thoroughly discussed this problem and pretty much decided it's not a big problem I think I'd be freaking out right about now. After having the heads up from the previous discussions, I was watching very closely as my canard came together. Sure enough, it wound up just like Marc's sketch, trailing edge about 1/16 to 1/8 inch low. After checking plans vs. templates, templates vs. plans etc. I think the answer is quite simple. It becoms apparant when you compare the canard hotwire template to the contour checking template. It appears that the bottom of the "fish tail" as shown on the plans is too low. Since the fish tail defines the location of the lower skin trailing edge, which in turn defines the position of the upper skin trailing edge, we have no option but to end up with the trailing edge a tad low as in the sketch. (That's my story and I'm sticking to it). Anyway, I feel a lot better about it knowing that I've got company. (Not to mention the fact that Roncz doesn't think it's much of a problem). Jim Hocut jhocut@mindspring.com