Smurphboy

Posted by TonyS on 13/12/2009 23:03:45: Hi Guys, My wife bought me one of these and I'm sure I'm missing something. I've finished the build and despite asking the chaps at Flying Wings for assistance, after the first reply it's gone silent so I'm coming back to you chaps.   First and most obvious point. All the publicity shots of the plane suggest there's a battery bay cover but mine didn't come with one i.e. the battery is open to view. Is this right?   Secondly, , having built it exactly to spec and using a 2200mAh 2S battery I needed to add around 100g of lead to get the CG on the underwing carbon spar. Again, is this right? The battery is a far forward as I can get it without cutting through the nose completely.   Finally, the thin carbon pushrods for controlling the ruddervators (?) were so thin that the flex affected the movement of the control surfaces. I've replaced these with snakes.   Has anyone else come across any of these problems?   T   I found that the battery all the way forward worked fine. I'd check how stiff your hinges are. The first time I made mine using UHU Por, they were really stiff and caused the problem you mentioned. I'd redo them and use two decent beads of Por pushed gently together, this gave a much more flexible hinge and less flex in the carbon pushrod. Its a great model though! I'm fitting a camera to mine for when the weather is better.

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Posted by Timbo - Moderator on 18/08/2009 12:24:00: Interesting...never knew that one Smurphboy - thanks for the link Seems odd that this formware limitation exists, after all, a channel is a channel is a channel surely? Oh well If you hunt around in the "other place" - there is another thread (I can't seem to find it at the moment) with a reply from Horizon acknoledging the fault - and stating that they don't intend to fix the firmware to address it. I assume its a bug and not intentional as you can use all the other channels as a slave to a mix. If the DX6i had three mixes then it could be worked around but as you are limited to just the two then it isn't possible without allowing the throttle as a slave.   SM 

Posted by Timbo - Moderator on 18/08/2009 12:01:21: That mix problem is a new one on me   Firmware "bug" ...says who ??  My understanding (see link) is that you can't have the throttle channel as a slave on a mix on a DX6i so you can't mix rudder and throttle together to get differential throttle. Hence I've got a v-tail mixer.   RC Groups post on DX6i Throttle Mix problem 

I'm using a v-tail mixer to mix the rudder and throttle together (you can't do this on a Spektrum DX6i due to a firmware bug) so that throttle controls both motors and rudder introduces a differential speed between the two motors.   Thanks for all the advice so far. I think I'm going to stick with the plan and extend the ESC to Batt leads. This should leave a neater wiring layout overall. 

I'm looking for some advice. I'm building a Goolie - great model but I've got a problem.    The plane has twin electric motors that you need to wire up to two ESCs and in my case a v-tail mixer. I know that I need to remove the red wire from one of the ESCs so that I don't blow my recevier and I know that I need to wire the battery to both ESCs. The question I have is what is the best way to do it.   I've seen (on another forum) that some people have extended the ESC to Battery lead and mounted the ESC next to the motor (having chopped the ESC to motor wiring right down) but it isn't clear if they have made the T-piece near the battery or further down or if that even matters? The instructions recommend this method but I've read that you shouldn't extend the ESC to battery wires and I'm not feeling too confident about wiring the motor wires direct onto the ESC.   The other option is to keep the wiring between the ESC and the motors and mounting the ESC on the fuselage - but that still leaves the wiring of the t-piece at the battery end.   A long question I know - but hopefully that makes sense??? 

Posted by Dusty on 25/06/2009 21:41:48: Smurphboy I did not know you had a Aero Engineering degree and did not mean to insult your knowledge, I am a redundant CPL pilot if you want to call it that? models and full size generaly behave in the same manner!   It came accross that it was to windy to fly the type of model? IMO! No worries. You might be right about the wind though - thinking back, I was really struggling upwind and really throttling back downwind so its possible I was close to the stall and the gust just caught me out. Theory and practice are two different beasts! Thanks for the help.  

Posted by Dusty on 25/06/2009 20:25:15: Understanding the priciples of flight would answer all your questions and make you become  more vigilent of what your flying machine is doing! By the sounds of it you were on the high end of the flight envelope of the model and nearing a disaster (IMO i am not familiar with this type)!!    I think I understand the principles of flight (have an Aero Engineering degree) but I wasn't expecting the a/c to behave like that. My thought was that the dihedral of the wing should prevent a spiral dive but that is how it appeared to behave. Conversely, the wind does cause the high side of the wing to balloon up into the wind so made its a feature of the a/c. Has anyone with experience of this model had a similar problem? Dusty: You do make a good point about nearing disaster - I wasn't flying nearly high enough to recover from the resulting dive! Lesson reidentified... 

Hello all, First time poster here so be gentle on me!  I've just bought and built a Flyingwings V-Trainer and think I've got it trimmed out nicely. (lovely aircraft by the way) I've been doing circuits and tonight it was pretty gusty (a/c was struggling to make progress upwind when the gusts were strong), and I had a real problem turning cross-wind after my downwind leg. As I turn, any gust tightens my turn and dives the aircraft quite dramatically.  Is that normal? Am I doing something wrong? I've only had one prang as a result (mostly me being heavy on the throttle trying to recover the dive) but I'm not sure it isn't a trim or other issue. All help welcome! SM