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OpticsNerd wrote: ↑December 10th, 2019, 10:28 am I'm having an issue right now. So when I fly with right turns my plane stalls with high torque but then slowly transitions to a dive over about 30 seconds as the torque decreases. The strange part is that this only happens with right circles; it actually flies very nicely with left circles. I've tried adjusting the shim to change the twist of the wing and changing the angle of the rudder to change the circle radius but neither fixed the problem. I'm also 95% sure nothing is moving by a significant amount during the flight. If anyone has any ideas please tell me. I really can't afford to continue having the right turns hinder my performance at competitions.

lechassin wrote: ↑December 10th, 2019, 3:02 pm

OpticsNerd wrote: ↑December 10th, 2019, 10:28 am I'm having an issue right now. So when I fly with right turns my plane stalls with high torque but then slowly transitions to a dive over about 30 seconds as the torque decreases. The strange part is that this only happens with right circles; it actually flies very nicely with left circles. I've tried adjusting the shim to change the twist of the wing and changing the angle of the rudder to change the circle radius but neither fixed the problem. I'm also 95% sure nothing is moving by a significant amount during the flight. If anyone has any ideas please tell me. I really can't afford to continue having the right turns hinder my performance at competitions.

Once we have a decent flying plane, we do the fine-tuning in the same order every time we change something: first tweak the CG to achieve nice recoveries (HVAC or touches), then set the rudder to get a good radius, then tweak decalage to get a flat cruise. We do that with partial winding to speed up the process. Don't hesitate to fly right and left with different decalage settings. I recommend the decalage all be in the wing, keep the stab neutral; this creates a down thrust effect that helps control launch angle (you can add actual down-thrust, we have not). Only after we have a nice cruise do we worry about the launch.

To the left, we never had much problem: higher launch torque just makes the plane bank steeper at first, which controls the climb angle semi-automatically. You may be experiencing a similar thing.

To the right, we had the same problem as you. Compare these videos from early and recent flights. In each of these videos the cruise is nice and you can clearly see the launch evolve; again, we make sure we have a good cruise before working on the launch:
https://www.youtube.com/watch?v=u77yWYz5yow this launch doesn't stall but it also doesn't climb high enough. We kept the launch from stalling by launching at low torque, so fewer knots/less power, ergo shorter flight time, not ideal.
https://www.youtube.com/watch?v=gIZRCyUUGVY&t=34s higher launch torque, we're getting good height and better times, but now the launch is a concerning affair. I predict this is what your plane will do once you get the cruise to stay flat.
https://www.youtube.com/watch?v=yju4a7rvPm8 this one's perfect. I especially like this flight because it confirmed the effect of the rudder. In this case we had too much: just prior to this flight I launched the plane into a slow descent. I intercepted it right away, decreased the rudder a little, and tossed the plane again into what has remained our best setting. If it had launched into a stall, I would have increased the rudder. It doesn't bank much going to the right, so I think the rudder is affecting the amount of side slip. I'm really not sure why, but it works perfectly for us. Interestingly, the rudder adjustments at this point are tiny and the cruise radius doesn't change.

Sadly though, there's still a lot of fiddling; an improvement in launch often causes a problem in cruise, or vice-versa. One thing that's a total freebie is a flaring prop]. The plane won't pull away as steeply when you launch at higher torques, and cruise won't change at all. I think this year's planes really need that to launch well and get good height.

CrispyFern wrote: ↑December 12th, 2019, 5:29 am I’m struggling to push past around 60 seconds in both directions. I think everything is trimmed pretty well but my motors might be the problem. They are pretty thick ~.12 and fly at around 2500 turns and .5 in oz of torque. The motor is at 5-10 winds when my plane lands. I’ve seen a lot of talk about thinner motors as lower torque. Should I start to focus on how I make my motors to improve? Am I correct in thinking that thinner motors will allow for more winds but lower torques?

bjt4888 wrote: ↑December 12th, 2019, 10:10 am Xiangyu,

Best of luck. Fly well.

My teams are in competition with you, but I truly want everyone to do their best and have fun.

Brian T

xiangyu wrote: ↑December 12th, 2019, 10:21 am

bjt4888 wrote: ↑December 12th, 2019, 10:10 am Xiangyu,

Best of luck. Fly well.

My teams are in competition with you, but I truly want everyone to do their best and have fun.

Brian T

Thanks! Good luck to your teams, too! I look forward to watching them fly!

Xiangyu

newflight wrote: ↑December 12th, 2019, 8:28 pm where are you competing this weekend?