Ben-Erik Ness

Back in 2010 I was waiting for the Windrider 737 to arrive, and since it took some time I started another build. The McDonnel Douglas MD-83 was based on drawings from scale-parkflyer.de. Back then I got it nearly finished (95%) and then the 737 showed up - and the project has been stored ever since. The 737 is long gone, so it was time to finish the MD-83 project and fly it! Plans where from www.scale-parkflyer.de (now also availible with a precut depron piece set) and the specs are as follows: Wingspan: 1300 mm (51") Fuse length: 1670 mm (65") RTF weight: 1250 grams (39oz) Power: Two55 mm brushless EDFs Here are a cople of shots from the first meeting in the season (yes, it is a frozen lake!) The development within the field of EDF has come a long way over the last 12 years, but I opted for keeping the old fans - and it actually works, not too much power, but enoug to get of the ground (ice) and do well in the air. It need some speed, the wings are not big at all! Enjoy video and pictures! Drone video of the maiden flight: Video of the second flight:

Time for some reflections after yesterdays maiden flight: CG was spot on at 150mm from the leaning edge at root The re-hinging, from bottom to top hinge on the second set of flaps gave me full authority over the aircraft The setup of butterfly for braking up before landing was also spot on. If flew very nicely, no bad habits on the first flight (20 minutes) The second flight had to be abandoned, due to the clevis attached to one of the main flaps snapped loose out of it's rudder horn. In the future I will bring spares. They are easy to replace and I have plenty. making a stronger horn will make repairing much worse and expensive It looks good in the air. Penetrates quite well. Keeps speed quite well too. Next is dummy engine pods with spinners! Looking forward to the next flight for this one

Successful maiden yesterday! Full report later! Full video soon! ??? VID_20210622_204915.mp4

Snow has left us and flying season is here! Decals are on as well ? In order to get the Dash-7 flight ready, I decided to cut lose the mid flaps, remove the lover hinge and top hinge them in stead. This will give both flap movement and better aileron control. CG has been set at 150mm from the leaning edge, and I had to add 850g of ballast in the nose to acheive that... Not too happy with that, but can't blaim anyone else than the designer. She ends up a tad over 5Kg ready to fly - so I will need more than a light brezze to fly her. This weekend I should of course have been at the Grat Orme, and one day this bird just might fly there! Fabolous pictures. Next weekend we have a slope meet coming up, and for the first time I had to check if thefuse fits in the car. I'm a lucky man ? The weather forcast gives us flying wind, bun not too optimistic about maiden, I don't think it will be enough wind at these slopes for this kind of plane. Time will show! Thanks for all input so far!

Thanks for all input on CG. I may have done a major f-up... And it messes with my CG. I have 2 degrees positiv eincidence on the main wing... Why? I because I have that on a powered plane of slightly smaller size, and i flies great. I have consulted a few "experts", both knowlegable modellers and professional glider designers, and they all end up with roughly the same calgulation (incdence calculated into the equation. So my CG ends up at 15omm from the leaning edge at the root. I feel calmed and confident that it will work. As you know nose heavy planes are a pain to fly, a tail heavy plane only flies once... I'm waiting for stickers for livery and windows, and two new servos that I have to change, one of the Futaba 3150 actually burned during a test - without load... My favourite slope where maiden will find place is still covered in snow, and the weather the last tree days has not helped ?

Calculations.... Maybe I shouldn't have started this discussion with myself ?... eCalc says: between 19,7 - 20,6 cm from leaning edge Aircraft Center of Gravity Calculator: 18.8 cm from leaning edge When measuring the root at the wing and listening to my gut feeling i'm more at 16 ish centimeters from the LE at the root. I'm considering various options: Make a chuck glider and see how it flies, maybe find a gentle slope and try the plane somewhere else than the grand big slope... Any input will be appreciated!

Okay, here goes again, and now the map is in sync with the terrain! Thanks to the trained eye of Gary Binnie who spotted my errors! Ben-Erik

I think you read my mind.... ? The "distance to the tip leaning edge is 15cm and the equivalent distace from the tailing edge is 10cm. The corde at the tip is approx 17cm (rounded curve) Again, very well observed! The floor is nice too... Ben-Erik

Very well observed, I think I have to go back and meassure on the wing and not the drawings. I have so many versions of drawings, and I think I might have used the wrong edition here... Back later this afternoon with updated and dependable meassurements.... Ben-Erik

Thanks for your input! There is some washout built into the wing yes, and I will mix ailerons up when landing, like a traditional butterfly setting we use on the 3m F3F gliders. I don't care too much about scale, that's why I don't have any undercarrage ?

Next challenge! Where do I place CG for maien flight? Any qualified answers will be appreciated. (In the end the decission is mine alone, and I'm the one to blame if everything goes down the drain on the maiden....)

Out of the paint shop! I hate rattle cans, I have never got the hang of it. So, it's far form perfect - but good enough! Before having my decals made by a mate (who runs a signshop) I usually test them fist, printed on paper, and attach them to the model. Pretty happy how it turned out. Next now is to get the decals cut, and in the meantimehook up all servos and connections again. The slope where I intend to maiden the Dash is still coverd in snow, so I got a few weeks before it can fly... Pretty happy with how it presents is self ?

Rattle can time... Now it's time for all the imperfections to stand out! But I don't think you'll see them on the maiden video, so I'll just live fine with them and carry on making progress ?

Another milestone! Everything hooked up, all servos and flying surfaces. And it works like I intended Video! However I'm debating with myself if the outer flaps should move with the ailerons like they do now, would it contribute to adverse yaw? Any comments?

Milestone! I have a wing with all surfaces moving in the right directions, at the same time. There is still many adjustments to be made, but you get the principle! I hope that these big flaps will slow it down in order to land it slowly in tight spaces...