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So now I am to the point where I will be looking more into the motor configuration and addressing the flaps. I'll do some run-ups and get some RPM data with the 8x6 on the front and see whats what. Maybe try the 8x7.5 as well and see what my numbers look like. If I feel the need I will look further into running the LUA script to sync the motors. I believe that I can use a mix to add some UP elevator with the flaps to try and slow her down better for landings and not have the nose pitch over so violently.
Many thanks on the additional compliments. My contact at the EAA museum was hoping I could make it up for Airventure this year to have the model on display with the original. While this would be a DREAM, it would be a VERY long trip right after FFEast and additional expense that I just do not have. I was truly humbled by the offer and consider it one of my finest moments of this model's moments. It has never been my experience to have someone from a museum to give one of my models such high praise.
I took more family time last night rather than do prop testing. Well worth it and the family seemed to appreciate the time. I know that I've missed time with my kids for brief moments while building this model so I'm trying to pay it back to them. They have been so understanding about meeting deadlines and trying to troubleshoot so many issues. The lighting was pretty good last night so I got the wife out to snap a few more pictures to capture this moment more for me. This was my favorite shot.
For sure she is prettier than the Sikorsky. I did not put in nearly the time and effort for detailing. I burnt myself out really badly on the main portion of the build. For comparison... the Sikorsky was a <100 hour build. The Bugatti is about 400 hours. That is nearly a week of straight building. I confess that I did lose track of hours put in after about 150 but I've gone back through this thread to estimate the hours.
I've spoken to JB and we hope to try and get some coverage of the Bugatti on film. Perhaps someone can live stream the session through FB on the FT Fans page.
Did a little prop testing. I've got the telemetry logging in the radio now so I was able to easily grab plots of the two RMP sensors. Sadly, I honestly do not know which one is which motor. The interesting bit is that you can see from the image that the response is quite linear. As this was a static test, I believe the discrepancy at the high end is due to the increase in pressure differential. The 8x6 prop is substantially more thin than the 8x8R. I believe the prop is deforming as there was a notable change is sound at that RPM. I'll throw in the cut down 8x7.5 and see whats what.
I still need to program in a mix for the elevators for when the flaps deploy. I also need to check the CG. It has been nice not having to push on this project and enjoy the family. I did do some major cleanup in the shop again. I need to start my preparations for FF!
I wonder...... Now that you have access to the RPM information.. Seems you are pretty linear in the 9000 - 10500 range. How hard would it be to correlate that RPM to the throttle range like 1825 to 1875 as an off the cuff number and do like a limiter in the Taranis and or depending how comfortable you are with a steady speed in a repeatable pattern to do a throttle hold in that sweet spot.
Unless you are running a pid controller on the motors I think that would be an easier more viable option for matching the motors then a manual adjustment feeding off the RPM sensors. Even if it could be done automatically in the Taranis where telemetry reads the sensors and adjusts the rpm I think the constant chasing that match would be more work then the esc's and motors would be happy with at those higher rpms.
More data in actual flight would tell more most certainly but that may be an avenue to look down to be easier on the gear and mind.
The issue becomes more dynamic in the air. If you listen closely to the maiden, there are times when the RPM was fairly well-matched and others when it was not. I recognize that not everyone's ears are attuned to hear this but it is audibly noticeable. This is where the sync through the telemetry would be nice. The geared setups for F3A would entirely solve this issue but I'm not paying $1100 for one. While the sync may not be ready for FF, I do plan on continually working on it until it works. I cannot believe that with the tech, there are not folks with twin (or more) engine aircraft that do not want their motors in perfect sync. This is one of the crucial steps in large aircraft.