Mega size electric AP ship

[AZ ChopperCam]

Some talk on another forum has really got me thinking. There are some amazing digital video/cinema cameras coming out in the next couple years that rival the quality of 35mm cinema camera. They will weight about 15-20lb.

What if there was an electric ship outfitted with something like 1200mm blades that had an airframe weight of 12-14lb and could carry 25lb payload?!

What about twin Hacker A60-18L motors each on 12s10,000 FlightPower packs geared about 6.5:1 with 1200mm blades? 11-15 min flight time Something like a scaled up Joker?

the most difficult part of the entire project would be the main rotor head. Tail rotor could probably use Logo 10 main grips with custom hub on an 8mm shaft with cut down carbon blades (190mm?) Belt driven with 3/8 XL series timing belt. Stacked carbon frame design.

the twin motor design would be awesome I think.... if for some freak chance one esc or motor were to fail the other could still power the main rotor. maybe not enough for very long sustained flight but enough to make a powered auto ? each motor would need to have a Torrington bearing. doing it that way would eliminate the need for a one-way in the main gear hub to I would think.

Andrey..... you up for a seriously cool project? I'm down!!!

[askman]

finding the head that can handle this load is the issue, not to mention blade. frankly rest is easy. frame should be straight forward. gearing is not though. frame, tailcase and tail rotor system should be pretty straight forward. I remember NRI was also having issues sourcing heavy lift heli last year. I wonder what they went with.

looks like 800s are largest commonly available blade. hmm.

I think motor is less of an issue. only thing is you will need high voltage controller. (15S,s due to extremely low KV on the larger motor?) power jazz would work for this though. $500 esc.

http://www.heli-chris.de/product_info.php?cPath=96_6_57&products_id=1102


check out this heli and head. very beefy head design, but it is 1.8m heli. (800mm blade) probably easily handle bigger blade though. :)

http://verbrennerheli.de/

it uses vstabi flybarless system. I do think you need to go this way for Uber heli, as it simplifies the design. you will need 3 giant scale servos as well, which is ok. making things bigger is not too hard, but you really need to consider the power and make it safe. vstabi using reduntant power system and possibly diversity receiver for the radio. hmm, how about multibladed setup? with vstabi, I think it should be very stable and gives more lift. I guess I need to find out how much multi blade will help in generating lift. :)

sounds interesting. feasibility is another issue though. it only takes money. :) my cnc can only do 15x28, but that should be big enough for this heli. use 1/8" g-10 for the side frame. (better than cf for mission critical job, as it is good insulator and less likely to cause glitchs)

sounds cool

[GJestico]

Vario has a head that is BIG. I cant find the info on it, But I saw one at a funfly that a fellow is using to build a scale huey. Huge head parts. The thrust bearings are an inch across.
I had never before seen parts so big on a "model" heli. I as thinking much the same that DJ is now. hmmmm what if.
They huey was goin to weigh around 30 lbs. Huge fuse a 5 year old kid could sit in it. A net search is in order....

[GJestico]

http://www.vario-helicopter.de/uh-1d_turbine.html?&L=1
thats the mechanics.

[GJestico]

http://gb.vario-helicopter.biz/shop/product_info.php?products_id=37925

theres your blades. I think MAH has some biggies too that they custom make.

[loewermx]

What about converting a Vario XLV to electric? I was thinking about that yesterday. Man, could you imagine the sound you would actually be able to hear from the blades? COOL!!!! :glasses:

What size is the XLV anyway? 3m? I have always wanted one of those huge beasts.

[AZ ChopperCam]

Greg McNair was building a HUGE Jet Ranger at one time. HE sold the project before completion though. I recall it used 30 size main grips for tail rotor grips.

I'd be willing to invest some $$ in this project and I'll bet Tony Rawlings would too. There needs to be a ship designed that will reliably carry this camera

www.red.com

with this camera and the ship to carry it along with a capable pilot, charging $8K/day to hollywood movie production companies is completely doable.

This is a project I would really like to consider. Seriously.

[askman]

found this vario. 2500mm blade diameter. should be a good start by using this heli.

http://us.vario-helicopter.biz/shop/product_info.php?cPath=22&products_id=35466&osCsid=2cee64b66f3b953ffd2360113e54ff0d

just need to design a frame for it. make it much easier.

[k2pilot]

every time this comes up i mention this heli!

the vario benzin xlv.
http://runryder.com/helicopter/gallery/21541/DSC01935.jpg

http://us.vario-helicopter.biz/shop/product_info.php?products_id=35466

http://runryder.com/helicopter/gallery/11120/barry_017.jpg

http://runryder.com/helicopter/gallery/11120/barry_033.jpg

http://runryder.com/helicopter/gallery/11120/barry_029.jpg

http://runryder.com/helicopter/gallery/11120/barry_034.jpg

http://runryder.com/helicopter/gallery/11120/barry_026.jpg

http://runryder.com/helicopter/gallery/11120/barry_035.jpg

just look through this guys gallery,
http://runryder.com/helicopter/gallery/11120/


the xlv uses 1055mm long blades, should suffice. the thing is so open it wouldn't be difficult at all to stick some big ol batteries on there and carry a big load.

[loewermx]

HELLO! Just said that! XLV


Just kidding! :wink:

[AZ ChopperCam]

I'm in! Andrey, do you think the Vario XLV can be converted to electric and be able to carry 25lb? 1055mm blades seem a wee bit small. I was thinking 1200mm ???

[askman]

looking at the manual, it would be easy to turn it into rear motor mount design with short belt in the first stage. will give large room in the front the the camera mount. new side frame and way to mount a large gimbal for the camera. (probably ring type with 3axis roll stabliztion. ) definitely doable.

[askman]

hmm. it gets even better, I think the whole main frame is usable. just need new bottom plate with new motor mount on the back with some more reinforcement. makes it easier to adapt as new frame is not needed.

[fitenfyr]

You guys should talk to Taylor Drain (sp) at http://www.rchelijetworks.com/

Taylor had a gas XLV and has been flying AP for awhile now.

When I discussed the idea of using an XLV for AP he advised against it.

He felt the rotor RPM was too slow and the machine was very unforgiving of piloting errors.
In fact his crashed last year I think and last I heard he chose not to re-build it.

Taylor has worked with movie industry stuff and is VERY knowledgedable in all things Vario. :D

I like the concept, but I think the XLV in even close to stock form is not the answer.
However the head and tail maybe a good starting point for something better.

[askman]

we are talking about electric conversion. I would not go with gas. definitely higher head speed if it can be done safely. vario recommend 860rpm. definitely too low. I am thinking 1200-1300 if it can be done safely.

[AZ ChopperCam]

He felt the rotor RPM was too slow and the machine was very unforgiving of piloting errors.
In fact his crashed last year I think and last I heard he chose not to re-build it.

well IMO a 23cc engine on a 2350mm rotor is very inadequate. an electric conversion would be much better and a headspeed of 1100-1300 or so ought to work out.

[k2pilot]

Andrey you had me beat by 2 minutes! lol and that was because i was gathering up those links :mrgreen:

but yea i too have heard the xlv isn't the best choice. may aswell go with one of the higher end turbine ships, it can handle that extra weight no prolbem and can maintain a nice high headspeed.

[askman]

g230 motor is 14,000 rpm 3.6HP motor. (2700watt peak) must be about 16:1 ratio. neu 1915-1y on 12S would give about 1200rpm. marginal but usable. . 40lb setup will need about 2000 watt hover. it give 5 sq meter disc area. 8lb/m^2 or 128oz/m^2. heavy but not out of line on larger heli. kohler actro 32-4 is probably better option on 14S.

bad news though. benzin head is only rated for 850rpm on 2500mm setup. not strong enough head. :( need stronger mechanic. probably 14-16 mm mainshaft. the blade has 22mm root. need to look at some of the turbine guys and see what head they use.

[enigma]

what about a tandem design? You could then use two smaller discs and the tandems are made for lifting.

[askman]

just looked at airstar and their head is rated bit higher rpm due to aluminum hub. . probably squeeze 1000rpm out of 2500 blade. (airstar used to used benzin head, so I am figuring that it has same root) still bit low headspeed. bergen twin is rated to lift 25lb on 18lb frame on 810mm blade, so I am sure 2500 will be enough. bergen is 18mm root if it is designed for vblade.

airstar ccpm gas kit is 1600bucks, but don't know how good they really are.

[askman]

tandems have their own issues. harder to hover too, and mixing gets complicated.

[miami6]

is this heli belt or shaft driven ? LOL what would the gear ratio have to be ?

[askman]

after looking at the existing machines, asi/airstar international mongoose is looking like the most likely platform with MAH950 blade. (or possibly vario 1055) the design is very well suited and easy to make a new frame for aircam setup as it is direct eccpm and very simple design. . it is belt driven tail as well. (make it easy to stretch)

with 950, you can hit 1200rpm while 1055 is only good for 1020 due to heavy blades (380gm) vs 230 for the 810 and 300 for the 950.

the question is whether 950(effective 2290mm) is big enough for the load. if 810 is good for 15lb load, I would expect 20lb payload possible with 950. (and keep same diskloading) and don't know how well 1055 flies at 1000rpm.

for motor, a60 m15 is 215kv motor. at 15S turns 9000rpm. need about 8:1 ratio or so. better to go with actro 40-4 at 320kv. 17000rpm 15:1 ratio. almost perfect. to use cheaper esc, go with CC110HV at 12S with actro 40-4 and 11-1 or so ratio.

[fitenfyr]

How are you going to balance that much of a front load?
I mean 20lbs out front would mean a WHOLE lot of weight on the tail wouldn't it????
Putting the batteries back there would make sense, but then you have issues with long runs of cable to the controller causing reisitance.
Plus the boom would have to be of a substancial size to support say 3-4lbs on the tail at a pretty far out ARM.

Good luck guys it will be fun to watch. :D

[askman]

I will be mounting the motor in the back(since it is belt driven) will go a long way for the balance. you can also mount the battery behind the motor and keep the distance close. all this will be part of the main frame, so boom can stay without becoming big. (first stage is belt driven anyway)

the cool thing is that ASI design is very compact, so you can have the camera very close to the center of gravity. I believe this is doable. I am investigating the power setup. (actro 32-4 or 40-4 but 1915 may be usable. hacker a60 is doubtful) I may have to sell couple of my helis to finance this for prototype. I was thinking about getting a maxi, but this could be done for about same price.