Mike Stevens 5 Posted October 14, 2019 What are the fliers finding for elevator defection at their max cruise speed? Quote Share this post Link to post Share on other sites
longezdave83 0 Posted October 24, 2019 I think mine rides too trailing edge high. It must be about 3/8" above the faired position at high speed. I'm considering checking/lowering my canard incidence. Quote Share this post Link to post Share on other sites
Marc Zeitlin 79 Posted October 24, 2019 On 10/13/2019 at 5:47 PM, Mike Stevens said: What are the fliers finding for elevator defection at their max cruise speed? In order to answer this question in a useful manner, you have to discuss GW, CG location, which airfoil (GU or Roncz) and IAS. Without that, any comment will be meaningless. Quote Marc J. ZeitlinBurnside Aerospacemarc_zeitlin@alum.mit.eduwww.cozybuilders.org copyright © 2020 Share this post Link to post Share on other sites
longezdave83 0 Posted October 26, 2019 Marc is correct. I just presented a basic response. The above that I presented is at a CG of 102.8, GW of about 1255#, Roncz canard and roughly 190 MPH indicated. I verified all the above, except I only have screenshots near 190 MPH indicated. Quote Share this post Link to post Share on other sites
Marc Zeitlin 79 Posted October 26, 2019 58 minutes ago, longezdave83 said: Marc is correct. I just presented a basic response. The above that I presented is at a CG of 102.8, GW of about 1255#, Roncz canard and roughly 190 MPH indicated. I verified all the above, except I only have screenshots near 190 MPH indicated. Now we're getting somewhere. At almost the aft CG limit of 103", somewhat under design MGW and an IAS substantially higher than the design cruise speed of the airplane (remember, the Long-EZ was designed for an O-235 engine of 115 HP, so has a design cruise speed in the 120 - 125 KIAS range (call it 140 mph IAS), it's not at all surprising that the elevator would be reflexed up a bit. That's 50 mph over the design IAS, give or take - the elevator trim position will need to be higher than trail. There are O-540 powered Long-EZ's and Berkuts that will run out of up elevator at max power, and will still be climbing even with the elevator deflected full TE up (at well over 200 KIAS). Quote Marc J. ZeitlinBurnside Aerospacemarc_zeitlin@alum.mit.eduwww.cozybuilders.org copyright © 2020 Share this post Link to post Share on other sites
Mike Stevens 5 Posted October 27, 2019 Thanks to all for your inputs. I went ahead and installed my canard tips per plans and will probably mod once I start flying. Hopefully next summer. Quote Share this post Link to post Share on other sites
