MechMan183

So I was thinking, anyone think a scale-model of this craft would be possible? Considering a full-size one hasn't actually been built, you'd have to adhere to the fantasy specs of it, but I'd think it would be awesome if someone built a really scale version, say with actual engines powered by fuel and it would also need a computer to calculate how to adjust the fan rotors and so forth. Only problem I can imagine is that it might cost as much as a full-size car?

Gorgok

Take your standard 4 rotor heli thingy (just google image for quad rotor heli) spread the booms a little more apart/change some angles (to make the rotors more like a pair in front and back), add balsa nacelles, then cut some rigid foam body work (keep it as hollow as possible) cover/paint as you wish and you are done. Except for the fuel part, as these are generally electric because of the rapid response needed and simplicity of having a fixed pitch propeller on each motor.

Overall, as long as you can keep the weight down (of the scale components), i'd say this isn't hard at all.

MechMan183

Hmm....I see. I imagine you'd need some mechanism to rotate the fan ducts however for forward movement and so forth. I am aware it could be electric, but I'd want it engine-powered for a more realisticeffect. The huge air intakes on the front would be real, for a real engine. I will have to read more on this quad rotor heli though, thanks for the info!

Gorgok

I haven't seen the movie, I just googled the ships name you mentioned to get a picture, so had no idea the nacelles rotated. That does make it more complicated... Too complicated maybe, at least for a reasonable budget.

Though if someone has a kit for a V-22 or similar tilt rotor you could probably put 2 of them end to end and pretty much make it like that...

karlik

[link]http://www.youtube.com/v/PTbkwgvxNDw&feature=player_embedded#[/link]


[link]http://www.scalerchelis.com/phpBB2/viewtopic.php?t=11651&f=9&sid=3ebab196a3a18a44be57a1efdd3a0503[/link]

scalehelinut

Nice links Karlik, I forgot how cool the flying scenes were in the movie !! That is exactly how Aviation will go forward seeing models fly first ,then getting to the full size and making it work !! The future is so bright for aviation I have to wear sunglasses !!!

tmojosh

Hi, im currently building the scorpion 16 transport that is used several times to move the team in the movie. Tilting nacelles and throttle control are enough to control everythin, im going to have a vtail mixer as well and maybe add a tail rotor if needed. I also would like to do the dragon dropship your talking about. It would require tilt mixing for yaw and rear only need to move forward and back together. On my scorpion 16 transport im using a hitec 645mg high torque servos for the tilting nacelles and jr digital high speed for the tail. The motors im using are axi 2814/10 which make 60 oz each thrust. I imagine if you can keep the models weight below 5 pounds four contra rotating props would quietly lift and fly the model. I would stay away from actual ducted fan units , take twice the juixe and harder to keep a slow or stable hover.

tmojosh

Fyi , I managed to keep my budget below 350 and that included the dx7 radio and r600 spektrum reciever I invested in. you will need minimum 6 channels to control the model , 7 if you have landing gear retracts. If I can do this one for 350 I imagine you could do the dragon for 450 maybe less. There are contra rotating units ive seen , some on ebay that make 50 oz each thrust , thats 200 oz total. Honestly the best performance would come from variable pitch , much better reaction time as motors are already spooled to operating rpm. Ive seen tail rotors for 450 pro trex and 500 that might work well. Just get 4 motors , for rotors , 8 servos , 4 , 35
amp brushless motor controllers. 4 2200mah lipo batteries, ar7000 rx , rx battery. When I add up the for sure main components I come up with 3.5 pounds. Vtol hover needs 1.1 to 1 power to weight and 1.5 to 1 to fly well. 200 oz is 12 total max pounds thrust , you want to stay at around 75 percent power for efficiency. Thats 9.3 pounds thrsus and after the wieght of the body , fan ducts, props, ect that will prob be another 2 pounds if you keep it light , 3 if its a little heavier. Still well within capabilities of 4 ducted props or ro to rs. Take in mind a project with this kind of power will draw 200 amps maybe a little more at full throttle. Fortunatly each motor would have its own battery , I recomend 30c turnigy or higher lipo.

tmojosh

If anyone can get ahold of a dragon model of flyable size, more than 18 inches at least I could make a mold so copies can be made if more people want models I have seen a handful of people who would like to have one of these.