I do not know enough about the tech design on electrical ESC's yet to know if a Castle 50 has feedback as Brett is referring to, I suspect it doesn't, but I can say that the constant RPM from the motor has greatly reduced the windup in my ships. Not 100% but it is certainly better than the IC's I have.
No, that is not what I meant - without accelerometers, that is a governor system, which doesn't allow the motor to speed up very much, but also doesn't cause it to slow down when you would want it to. The feedback systems have accelerometers that sense the speed up and back the motor off to compensate.
If your IC system doesn't do better, it's probably because it is not configured correctly. More-or-less, if you are not comparing it to one of the known good IC systems (PA, RO-Jett, or VF), then you will not get there, and the electric will be better. What is your reference engine/prop/pipe length? Heavy air is where I think IC still might have an advantage (because the bandwidth of the speed controller limits the possible response of the feedback system - essentially, the feedback loop has to be slower enough than the speed controller to keep the combination from going unstable).
IMHO the windup is much less with an aft CG, leadouts as far forward as practical and a long tail with a large stab - all of which unfortunately reduce line tension.
Moving the leadouts forward might reduce the line tension, but the other things don't. The other things reduce the control loads, meaning that you *require* less tension. In any case, the issue with whipped up airplanes is certainly not lack of line tension, if it is whipping up, the problem is usually *excessive* tension, not inadequate tension. Thats why biasing the maneuver helps, it keeps the speed within the limits of sanity at the bottoms of the loops.
Brett
p.s. as an aside, this came up in another thread yesterday, and the casual ease with which people can get an acceptable electric system compared to the difficulty of getting an equally good run with an engine is where these "electric is AMAZING!" comments start - because, compared to most people's IC system, it is amazing and much better. I checked the "Engine Setup" forum yesterday and there wasn't a *single thread* that appeared to have anything to do with a competitive IC engine system in the year 2018. I don't fault anyone for running whatever they want, but it was striking to me that no one appears to even be aware of the remarkable developments of the last 30 years, or they are, but think it's nonsense and hype.
Given that, it's not at all surprising that the same people find electric to be breakthrough, almost any system you get that has a speed controller and will get through a pattern will work better than the best 4-2 break system and it will certainly be more repeatable. I think the best possible electric systems and the best possible IC systems are pretty even right now, with IC probably as good or marginally better in some conditions, and electric being better in some conditions. But compare even simple electric systems to the average IC system, and it's a blowout. That alone is going to make electric dominate the event, whether it's really better than a perfect IC system or not.
p.p.s. I did a quick brush through the Engine Setup pages, and it wasn't until page 5 until I got thread title that related to competitive engines, and that was from April! There are a lot of 20FP/25LA questions, those run much better than what most people are talking about, and there was a Aero Tiger question, which is much better than what most people run, but otherwise, nearly nothing about PA61/65, PA75, RO-Jett 61, or 40/46VF. That takes us back to at least *1990*, which is more than a *quarter of a century* ago.
Part of the issue, which has been clearly obvious for a long time, is that electric is not overburdened with "tribal knowledge" to nearly the extent that IC engines have. By "tribal knowledge", of course I mean utter and complete bullshit. So you can naively set up your electric and have it work, but no one can bring themselves to just leave their engine alone and run it. That alone would greatly improve almost everyone's rate of IC success. With feedback electric systems I can see some people starting to think they know how to "improve" it, and shoot themselves in the foot thereby, so I have every confidence that we will wind up with a similar steaming pile of tribal knowledge for electric in short order!
Topic: Wind Up . (Read 2127 times)