TMann Posted June 25, 2008 Share Posted June 25, 2008 Two questions for the group: 1) Why do the Canard Tips sweep up at the ends (for those who build that option) vs. curling under such as I see out on the flight line on Cessnas and the like? 2) Is there really a measured advantage to this (other than they look cool and poke people who get too close.) Quote T Mann - Loooong-EZ/20B Infinity R/G Chpts 18 Velocity/RG N951TM Mann's Airplane Factory We add rocket's to everything! 4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done Link to comment Share on other sites More sharing options...
Hercpilot Posted June 25, 2008 Share Posted June 25, 2008 First off let me say that I am no aerodynamicist! Now then, this is what I understand to be happening. The curved tips on the canard are acting like mini winglets and extending the wake vortex aft of the canard tip therefore serving to reduce drag from the lift produced by the canard. The curved down tips that you are referring to are for the purpose of STOL. They serve to contain the high pressure air and produce more lift at a slower speed. Someone please correct me if I am wrong! Justin Quote Justin http://web.me.com/hercpilot/Justins_Website/Welcome.html Link to comment Share on other sites More sharing options...
Marc Zeitlin Posted June 25, 2008 Share Posted June 25, 2008 Two questions for the group: 1) Why do the Canard Tips sweep up at the ends ... Aesthetics. 2) Is there really a measured advantage to thisNope. Quote Marc J. Zeitlin Burnside Aerospace marc_zeitlin@alum.mit.edu www.cozybuilders.org copyright © 2024 Link to comment Share on other sites More sharing options...
Steve Innova Posted June 25, 2008 Share Posted June 25, 2008 I don't have the source handy, but I recall reading that when NASA tested the veri-ez, the tried downswept canard tips. The results were bad -- the aircraft became unstable in pitch while transitioning from takeoff to flight, IIRC. I would do further research on this before considering it. Quote Link to comment Share on other sites More sharing options...
Hercpilot Posted June 25, 2008 Share Posted June 25, 2008 Marc, So am I off on my understanding? Justin Quote Justin http://web.me.com/hercpilot/Justins_Website/Welcome.html Link to comment Share on other sites More sharing options...
Marc Zeitlin Posted June 25, 2008 Share Posted June 25, 2008 I don't have the source handy, but I recall reading that when NASA tested the veri-ez, the tried downswept canard tips. The results were bad -- the aircraft became unstable in pitch while transitioning from takeoff to flight, IIRC. I would do further research on this before considering it. Don't know about the VE, but there are COZY's/LE's flying with downswept tips, and they do not exhibit behavior any different than chopped off tips or upswept tips (or any other weird tips that folks have tried). I'd be interested in a pointer to that NASA report. Quote Marc J. Zeitlin Burnside Aerospace marc_zeitlin@alum.mit.edu www.cozybuilders.org copyright © 2024 Link to comment Share on other sites More sharing options...
Marc Zeitlin Posted June 25, 2008 Share Posted June 25, 2008 Marc, So am I off on my understanding? Not necessarily, in a general sense - it just may be so tiny an effect on these canards that it's not measurable in either direction. Quote Marc J. Zeitlin Burnside Aerospace marc_zeitlin@alum.mit.edu www.cozybuilders.org copyright © 2024 Link to comment Share on other sites More sharing options...
TMann Posted June 25, 2008 Author Share Posted June 25, 2008 Thanks for the input everyone. On the Berkut construction tapes, Dave demostrates how to make the upswept tips but coveyed the opinion that they were not what he preferred. It's been a while since he made the tape and I thought I would check to see if any new information existed. I had no intention to build with a downward curve and the jury is still out as to whether I go straight (my parole officer would be so pleased) or sweep the curve upward. I figure it will be a done deal in a couple of weeks and I'll know for sure at that time. Quote T Mann - Loooong-EZ/20B Infinity R/G Chpts 18 Velocity/RG N951TM Mann's Airplane Factory We add rocket's to everything! 4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done Link to comment Share on other sites More sharing options...
Steve Innova Posted June 25, 2008 Share Posted June 25, 2008 I'll try to find the source; I'm sure I didn't completely imagine it. We'll see... Quote Link to comment Share on other sites More sharing options...
Marc Zeitlin Posted June 26, 2008 Share Posted June 26, 2008 I'll try to find the source; I'm sure I didn't completely imagine it. We'll see...The NASA report of testing on a VE with which I'm familiar is NASA Technical Paper 2382 from March, 1985 - "Wind Tunnel Investigation of a Full Scale Canard Configured General Aviation Airplane" by "Long P. Yip". While numerous parameters (canard airfoil, canard incidence, canard position, winglets, leading edge droop, etc.) were adjusted and stability of the aircraft was measured, canard tip shape wasn't one of them (from a cursory examination of the TP). Quote Marc J. Zeitlin Burnside Aerospace marc_zeitlin@alum.mit.edu www.cozybuilders.org copyright © 2024 Link to comment Share on other sites More sharing options...
TMann Posted June 26, 2008 Author Share Posted June 26, 2008 .....on another note: I applied the bottom skin to my canard tonight and managed to vacuum bag it as well. I did a trial fit last night and determined that if I added enough slack/pleated etc. in the right areas, I couuld slip the entire jig assembly into the bag, I cut the standard jig templates and then notched them to accept 2 12 foot runs of 1 x 2 extruded aluminum. The vacuum bag snugs the canard core against the extrusions for a guaranteed straight cure. I'm using the method Dave R. uses in his Berkut video, for the top skin. I'll build my jig for the top skin using a jig that will consist of a 1" x 4" x 12' piece of extruded aluminum and a 1" x 2" x 12'. The trailing edge will be bonded to the 1 x 4 and the nose (behind the overlap area) will be bonded to the 1 x 2. Based on the experience of the bottom skin, the entire jig should go in the bag without a problem. ........ thinking outside the box. Quote T Mann - Loooong-EZ/20B Infinity R/G Chpts 18 Velocity/RG N951TM Mann's Airplane Factory We add rocket's to everything! 4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done Link to comment Share on other sites More sharing options...
airnico Posted June 26, 2008 Share Posted June 26, 2008 Tom, May you post some pics of this procedure please? Quote Roads? Where we're going we don't need roads. (Dr. Emmett Brown) Link to comment Share on other sites More sharing options...
TMann Posted June 26, 2008 Author Share Posted June 26, 2008 Yes, I will post some pictures. I'm behind in that area. I need to reload software and unload the camera. I promise ........ pictures soon. Quote T Mann - Loooong-EZ/20B Infinity R/G Chpts 18 Velocity/RG N951TM Mann's Airplane Factory We add rocket's to everything! 4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done Link to comment Share on other sites More sharing options...
TMann Posted June 27, 2008 Author Share Posted June 27, 2008 I don't know if you can tell but there is a lot of extra slack in the bag around ends an jigs to avoid tearing the bag as I draw down a vacuum. Pic 2 is the layup in the bag on my new and improved construction table. Note the electrical outlets at both ends. Handy stuff. On the right side you can see the vacuum guage and vacuum switch. The Pump and resevoir are inside the cabinet. I ran another outlet in there to plug the pump into. The black pipe that runs under the edge of the table has several connection points for me to tap into so I can run more than 1 layup at a time (which I have done in the past.) I'm remodeling my basement shop during all this and took my epoxy cabinet down and was lookin for a place to stow it and set it on a small table equipped with casters. I'm leaving it there......it's great! I can wheel it right up to where I'm working and get it out of the way when I don't need it. Quote T Mann - Loooong-EZ/20B Infinity R/G Chpts 18 Velocity/RG N951TM Mann's Airplane Factory We add rocket's to everything! 4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done Link to comment Share on other sites More sharing options...
TMann Posted July 23, 2008 Author Share Posted July 23, 2008 Got my jig put together for the top spar cap and top skin for the canard. The canard is not bonded to the jig in this picture. I used a 1 x 4 to secure the trailing edge and a 1 x 2 to secure the bottom towards the front. After putting it together it seemed only obvious that an additional 1 x 2 added to the nose area (when combined with the 1 x 4 at the TE) will provide a nice set of rails upon which I can run my WHCMM. (the Wayne Hicks Canard Milling Machine) That should ensure that the canard top surface will remain true to the design. It could be a busy weekend coming up. Quote T Mann - Loooong-EZ/20B Infinity R/G Chpts 18 Velocity/RG N951TM Mann's Airplane Factory We add rocket's to everything! 4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done Link to comment Share on other sites More sharing options...
TMann Posted December 2, 2008 Author Share Posted December 2, 2008 I managed to get the top spar cap done on the canard this weekend. I filled the bottom trailing edge with micro prior to skinning in hopes of gettin the closest shape possible to the templates. That will be difficult to work with trying to get it cleared off down to the bare glass and make sure that all the peel ply is gone. I've tried a couple of methods but the Fien with the scraper blade seems to do the best job with the least amount of damage. I hope to be past this by the end of this coming weekend. In the Berkut tapes they micro as soon as the skin layup is cured. working ...... working..... Quote T Mann - Loooong-EZ/20B Infinity R/G Chpts 18 Velocity/RG N951TM Mann's Airplane Factory We add rocket's to everything! 4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done Link to comment Share on other sites More sharing options...
Phil Kriley Posted December 2, 2008 Share Posted December 2, 2008 I did not sweep my canard tips up or down - instead, I tried my best to copy the wingtips on Nemesis and Relentless (and another plane that I forget the name of) - they make a graceful curve aft of the trailing edge of the elevators and end in a point. I like the way they look! Quote Phil Kriley Cozy #1460 Chapter 13 - nose Right wing done - working on right winglet. Link to comment Share on other sites More sharing options...
Wayne Hicks Posted December 2, 2008 Share Posted December 2, 2008 I won't intentionally attempt to influence your choice, but.... If I had it to do over again, I'd go with flush, rounded tips. No curvies, no trailers. They have have a tendency to snag anything that walks by. I caught my shirt sleeve on my curvy a while back and delaminated the upper glass curvy from the bottom glass curvy. I've also put a nice scrape on my gut because I cut the corner too close to the curvy as I walked around the canard. For all their cosmetic benefits, they are fragile and they are sharp. I would imagine the issue would only be worse for me if something was trailing from the tip of my canard. Quote Wayne Hicks Cozy IV Plans #678 http://www.ez.org/pages/waynehicks Link to comment Share on other sites More sharing options...
Phil Kriley Posted December 2, 2008 Share Posted December 2, 2008 You're right, Wayne - they are sharp! My son and I have a bet as to who will get caught on it first! The picture I have of Relentless features a tennis ball over the point... But they really look good, so I'm going to keep them - at least until they draw my blood. Quote Phil Kriley Cozy #1460 Chapter 13 - nose Right wing done - working on right winglet. Link to comment Share on other sites More sharing options...
TMann Posted December 2, 2008 Author Share Posted December 2, 2008 I won't intentionally attempt to influence your choice, but.... If I had it to do over again, I'd go with flush, rounded tips. No curvies, no trailers. They have have a tendency to snag anything that walks by. I caught my shirt sleeve on my curvy a while back and delaminated the upper glass curvy from the bottom glass curvy. I've also put a nice scrape on my gut because I cut the corner too close to the curvy as I walked around the canard. For all their cosmetic benefits, they are fragile and they are sharp. I would imagine the issue would only be worse for me if something was trailing from the tip of my canard. That sure is something to keep in mind. Now that you mention it (when I was a cabinet maker) we always tried to knock off the sharp corners of the counter tops because at 36 inches off the floor, they were just the right height for kids foreheads. I'd hate to have a VERY young eagle to get injured why looking at some futuristic airplane. If I do the sweeps, they will be rounded. I don't think it will have any effect on airflow. I'll reserve any pointy terminations (if so inclined) to the tip of the winglet (to help fend off giants.) Quote T Mann - Loooong-EZ/20B Infinity R/G Chpts 18 Velocity/RG N951TM Mann's Airplane Factory We add rocket's to everything! 4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done Link to comment Share on other sites More sharing options...
longezdave Posted December 3, 2008 Share Posted December 3, 2008 I'm certainly not going to argue with any of the above. I think that the different possible shapes that you could put on your canard tips are going to be very close in performance. Any difference in performance from tip to tip would probably be hard to measure......BUT, I chose to go with the Roncz canard plans curled up tips. In CP 43, page 2, referring to the curled up tips, it says "These tips are specifically optimized to enhance the vortex coming off the tip of the canard and position this vortex in the "sweet spot" over each main wing". With that said, I think the most important thing to do with the tips is......TO GET THEM FINISHED. Quote Dave Adams Long EZ N83DT Race 83 Link to comment Share on other sites More sharing options...
TMann Posted December 3, 2008 Author Share Posted December 3, 2008 With that said, I think the most important thing to do with the tips is......TO GET THEM FINISHED. SOMEBODY SAY AMEN !!!!!!!!I couldn't agree more. Quote T Mann - Loooong-EZ/20B Infinity R/G Chpts 18 Velocity/RG N951TM Mann's Airplane Factory We add rocket's to everything! 4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done Link to comment Share on other sites More sharing options...
mfryer Posted December 3, 2008 Share Posted December 3, 2008 SOMEBODY SAY AMEN !!!!!!!! I couldn't agree more. I will second that. I just finished mine a couple of days ago. Really fun sculpting the shape. Quote Link to comment Share on other sites More sharing options...
TMann Posted December 5, 2008 Author Share Posted December 5, 2008 All set for the top skin this weekend. That will finish out Chapter 10. Doing 10 & 14 at the same time seems to work. I'll start 11 next week. I also order my parts for 13 so that's will be going on at the same time. 12 looks pretty short so I'll be tryint to work that in while I have glass curing. I'll be anxious to see how much progress I can make by the first of March. I really would like to get that canopy out of the box. Quote T Mann - Loooong-EZ/20B Infinity R/G Chpts 18 Velocity/RG N951TM Mann's Airplane Factory We add rocket's to everything! 4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done Link to comment Share on other sites More sharing options...
TMann Posted December 8, 2008 Author Share Posted December 8, 2008 I ended up spending more time on Chapter 14 than I thought. I moved back to the canard late in the afternoon and pretty much have it ready to glass. I'm planning on cutting a profile template to check the top contour just to double check prior to glassing (in hopes of minimizing filling.) I still believe I can have this complete and move on to another chapter by the end ofthe week. Quote T Mann - Loooong-EZ/20B Infinity R/G Chpts 18 Velocity/RG N951TM Mann's Airplane Factory We add rocket's to everything! 4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done Link to comment Share on other sites More sharing options...
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