Amazing first flights Chris. That it flight hands-off means not only was C/G spot on, but that timed for the current mass and an airspeed near centre of flight envelope. Know you poured tremendous amount of research and effort into this build, but with maiden you make it look so effortless. This a huge accomplishment. Congratulations! Not sure the vibration you were referring to, but the sound came across in the video as sounding similar a mini-turboprop with the mid-range throttle flybys.
Awesome! I have been watching this build and reading the comments.... some people's children.😆 Your first flight is fantastic, awesome confirmation of a great build! Also, nice runway and location!
My experience with twins.... they fly amazingly straight and stable. Even a crappy, old DZ500 turned to twin-motor configuration went from terrible to great. Amazing footage, well done!
A wonderful ~trick to chill out a plane with excessive roll rate is to put differential between the two ailerons. Have the aileron go up about 50% more than down. Aside from it smoothening out the roll, it's actually more efficient. When the aileron goes up, drag is created. When the aileron goes down, drag is created. If you look at the drag created by both above conditions (assuming the up and down is equal), the down aileron creates more drag. This creates unwanted yaw favoring the down aileron. Adding differential is one of the greatest tricks someone told me about. It makes the plane fly SO much better! Your trim for a 1st flight was just unreal! Great job!
Very nice, well done! Looking forward to seeing many more flights! Be careful flying low and slow until you are comfortable with the way it handles at low speed, I was keeping my fingers crossed for you... haha
I don't know what's more exquisite, your home designed twin plane or that beautiful weather...It was amusing to see it had landed surrounded by Cow Pat's?...but missed them all somehow...and your still using that cheap Flysky radio!!! Well done though, it's a thing of beauty m8....🤔😳😀😀😀😏🇬🇧
I'm looking forward to seeing you cram every battery pack you have into it and seeing just how long she'll stay up! Happy new year from the cold side of the globe!
If my calculations are correct and it can carry a 5kg payload, making the entire payload of 18650 cells would get about 4 hours flight time. Actually not that impressive when you consider what smaller planes are capable of when purpose-built for endurance: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-HGZC-cvYcb8.html ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-SxVG7H_Hc-c.html
I'm here for the right reasons but the terrain around you had me dreaming of ripping dirt bikes or maybe a desert truck just touching the tops of the hills at about 120. You are definitely way out there.
after a lot of research i realized that the only viable solution for a "large" aircraft to be long range is an IC gas engine. All the research shifted from trying to find the biggest batteries available to vibration reduction. Everything is a compromise. Excellent work BTW!
Beautiful location. Apart from those trees that always have a habit of reaching up and dragging planes out of the sky. Next time, take a chainsaw with you. Joking aside, nice plane. When gliding don't forget those props will be acting like big brakes. Folding props and motor braking will make a lot of difference when gliding. Certainly worth thinking about if you wish to extend flying times. Dont worry about missing the video with the final landing, any glider pilot can tell it was good from the sound of the grass being compressed. Well done, all good.
"Not a great glider" - who'd a thought that a 7kg cargo plane wouldn't be a great glider 🤣 nonetheless a great uneventful maiden - nice one and happy new year to you too
@@iforce2d Agree, expect should see noticeable difference with ESC braking. Those large propellers can act like wind turbines, thus producing significant drag action. While useful for steepening a landing approach, not so much trying to glide.
Nice to see this video, you should have taken it to visit the boys down at Tokoroa with uncle Bruce 🙂 Maybe you will be doing that in 2023, a happy new year to you too Chris!
I might have to do that for a 5kg payload, this setup probably doesn't have enough power to get airborne in a short space. I could just let it go over that concrete edge and hope for the best maybe, but landing would also need more space.
@@iforce2d : Autonomous mission:- Fly to TKZ empty. Land. Allow ten minute turnaround so uncle Bruce can top it up with Heineken. (Make sure he uses cans, not bottles... you want to be limited by space, not payload!). Take off from the nice long runway! Fly back to "El Rancho de Chris". Land using overweight landing protocols (Recommend long shallow approach, to minimise cargo frothing.) Recharge for next run, while Chris lounges back and raises glass to toast the sunset and technology! 🍺 Here's to a great 2023! 😋 👍
Super flight. Do consider making a few videos on how to get started with learning to fly RC planes.I am sure there are tons of videos out there, but your style is more enthralling.
Wow Chris, what a maiden. Hands off manual - geez. Just amazing. What a gorgeous beast that thing is. That vibrating sound is surprising. My twin motor setups just sing and are really quiet. Made me think one or both of the props was out of balance, but I'm sure that's the first thing you checked. Maybe the "open" design of the nacelle? I was thinking maybe the combination of propwash and the open nacelle were combining just right to give you the vibrating sound? Maybe just enclose the nacelle? In any case, just another incredibly enjoyable video. Love it! NOW LETS DROP SOME $#!T!!! 🤣🤣 Happy New Year to you too, man.
The props were nicely balanced when I started, and they don't take much of a hit from the grass when landing so I think they would be ok still. The nacelle structure feels very solid, and the bearing play I mentioned is actually so small I can hardly notice it. The vibrations seem to go away at slightly lower throttle so maybe it could be some kind of sympathetic resonance with the nacelles protruding forward so far. If so they would need some kind of damping. I might make a cover for the nacelles sometime, but mainly just for looks.
12:40 In case you don't know, the reason why you loose altitude so rapidly with the motors off is because the props are windmilling. This means they are producing thrust in a direction opposite of the aircraft's motion. Of course, thrust in the "opposite direction" is nothing but added drag. Therefore, the lift-to-drag ratio is substantially reduced (compounded by two props). As a professional aircraft designer, I have done substantial research on the effect of windmilling propellers on drag. Windmilling easily doubles the minimum drag coefficient. The hit is higher for "sleek" aircraft, because they already have a lower drag coefficient. Anyway, this airplane looks pretty sleek to me and should have a reasonably high L/D in cruise, evidenced by the low power draw at low to modest speeds. Overall, I think you've designed a good airplane of which you can be proud. I'm going to check out your flight test video too. Best wishes.
Yeah I did some research into this too, was flawed in some aspects though so might need to be revisited sometime: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Tn1OQui_9S4.html
Aah! I've been waiting for this! Seems like a beginner friendly plane! Wasn't so sure about the motor mounts initially but apparently it has proven itself capable. So, what's next? Landing gear perhaps?
Sweet. 220kph! Also a clean plane doesn’t take much to stay in the air if it has the right wing loading and speed, strangely heavy and fast can be efficient.
BEAUTIFUL spot to fly..........very nice. The plane's flight seems to have all of the characteristics of being slightly nose heavy. Just something you might want to play with the CG.
Once you go to counter rotating twin you never go back! Lol I have a diy build similar to yours. Setting the motors to brake will get you a lot better glide.
wow! Pronounced W.O.W You have quite the "eagle's next" there. Or should I say "Where Eagles Dare"? Very COoL. Last time I saw anything fly that well, I was on Vicodins. Cheers from So.CA.USA 3rd House On the Left.
Happy new year Chris. There is a way to do a mix with the flysky radios to get more modes in mission planner. I think using the three position and one two position can get five modes . I haven't done it for a few years but there is a couple of vids on yt showing how.
Yeah I've had 4 modes with it before (maybe 5?) but it's hella confusing. After finishing the auto-tune I set the modes to what I will use long-term, 3 is usually enough
@@iforce2d yeah I remember it being a bit of a pain to set up but I usually like to have a manual mode as well rth fbwa and auto. It's the biggest downside to the i6 radios , but other than that I really like them.
8:00 when I realized it was going to land very close to the camera I was like ''nooooo please not the puddle'' but it touched down to the left of the puddle and turned out to be an awesome landing for a first flight
Nice one Chris. I bet brake will help with gliding as right now it’s like having two parachutes when they freewheel. Always a treat when one of your videos is published - thanks!
Yes the props are balanced, or at least they were before scraping a bit on these landings. I think the motor mounts may just be too flexible and extended a little far forward, and resonance develops at some throttle levels.
AWESOME. I was never a fan of landing gears too !!! LOL Meanwhile it would be good for many who are not from there or have no idea WHAT IN THE WORLD is that patch of Concrete FOR !!! Guys thats for Top Dressing Ag Aircraft ... yep those pilots KNOW flying ... while we NO flying !! CHEERS. (correct me though)
I'm not a big fan of folding props in general, ok for light duty on a purpose-built glider I guess but not so much for a plane that needs more power. I will set the ESCs to brake and see how that goes.
Are there at least three points of support on the motor mounts? Also engage the ESC motor brake to stopp the props free wheeling/spinning with the power off. This will drastically improve the glide performance. Remember spinning props when not under power is a really effective airbrake!
You can see how the motor mounts are constructed in this video, look for the timestamps below: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-ABdhq0u6ViQ.html 6:14 38:52 The mounts are pretty solid but I think maybe they extend out too far from the spar.
Prop engines at idle are basically airbrakes, the airflow turns the engine & that's a lot of drag. Factor in that you have 2 engines & it's not surprising that the aircraft doesn't glide well.
