Totally delighted to hear from you. I had hoped we might hook up some time.
(Late edit) Contact now established between us. Most useful.
In short, I think your involvement and that of Rob Lewis saved the day as for as the Dr1 is concerned. It was obvious the incidence of the top wing was incorrect and you both came up with a solution which might otherwise have eluded us for many a long month.
George has also seen this thread which he read with interest. A link to it was also sent to DW for their information and perusal. It must of hit the spot down there in China, because they immediately mailed and thanked me for the thread and requested I review their next production offering!
I much enjoyed building the Dr1l but as said above, there were several issues needing important attention. The C of G issue was a glaring error. We all saw that immediately and corrected that in an instant.
The tail-plane and rudder were other obvious areas for major attention. DW in my opinion failed to understand that the tail structure, together with the torsionally weak rear fuselage needs some slight increase in cross sectional area and a revision to structure based on the I-beam principle. I see revisions as very necessary to impart a reasonable degree of structural stiffness. That Rob and I both added tail braces was proof enough that there is a substantial defect in design as regards the tail-plane.
Rob Lewis and I are currently both involved with trial building the latest DW offering...their Fiesler Storch which frustratingly also has the same type of rigidity issues. I`m a bit ahead on that build so have been able to ping Rob some images which I hope will assist him. Kits were sent to us both about three weeks ago for evaluation. I`ve had to address tail weakness on that model also. I have increased tail plane depth by 2mm by cross grain sheeting the basic DW structure to impart some torsional stiffness and strength. Indeed the leading edge of the elevators snapped on me as I lifted it off the building board...... One appreciates that the tail end of almost any model must be kept as light as possible, but DW in my opinion fail do not understand that this must not be at the expense of lack of intrinsic air frame strength or structural integrity. In the case of the Storch then, I have agreed to compile a report on my build findings once the model is finished. Presently, it is about 70% done and should be complete in about ten days.
George has been kept in the loop as regards the build of the Storch and has seen images of the areas which concern me on that model. Having been involved with two DW offerings now, my personal opinion is that the design and kits are under-developed in several areas. This is a shame because the core product and concepts deserve to be winners. I`ve also built both the Taiwanese SFM SE5a and their Fokker DV11 which build perfectly and fly even better. If the offerings from DW and SFM were placed side by side for comparison, then DW would struggle badly in the contest and SFM would romp home as winners leaving DW to trail in the dust. If DW could only come to understand what modellers require and indeed demand, then they might then become competitive. I`d like DW to make better kits. Whether that will ever happen is debatable. They will have to run hard to catch up with SFM.
The incidence issue was irksome and very concerning until you came up with the solution after which George pinged me a "heads up". We immediately spoke together about the problem. At the same time, I saw Rob Lewis`s RC Model Geeks videos and made contact with him. I was further able to brainstorm the problem. Thereafter, further words with George allowed him to see that there were issues with the development of the Dr1 kit and he took the matter up with DW direct. The problem is that the DW sales guy speaks English but the CAD man doesn`t! Thereby perhaps lays the nub of the matter. Details get lost and dumbed down in translation. "Chinglish" is not the ideal lingo with which to discuss aerodynamic subtleties!!
Having seen Robs videos of his DR1 in action, I have to admit to being rather shocked by what transpired. Rob had a most difficult maiden flight with the DR1 which left him clearly shaken and verbally dumb-struck. The model did not fly well initially but Rob later did a little more work to help some of the problem areas. Then winter set in and the 2018 flying drew to a close. This coincided with the conclusion of my own model build with my model being moth-balled for the winter pending better flying conditions. I don`t think Rob has latterly flown his example since his final 2018 flying session concluded. So it sounds to me as if we all have dormant Dr 1 models awaiting the 2019 flying season. Frankly, with more that three hundred hours invested in the building of my example, I`m almost terrified to have it flown! Lets hope it doesn`t end up as my five year old Grand-daughter once described it as potentially "A very expensive but exquisite little ornament"!
Good to chat on the phone this morning, Roger.
All the best.