Sean Plummer

Today I will begin posting the details of very Large Electric conversion project. The Model is actually an ARC Almost-Ready-To-Cover VON EXTRA 260. The standard powerplant is a Desert Aircraft DA-150 150cc gas engine. http://www.desertaircraft.com/engine...hp?Page=DA-150

This plane is well know in the IMAC/TOC competitions.This model was chosen for it's very light weight and compatibilty for electric conversion. This all laser cut Balsa design has great flight characteristics for both Pattern and 3D.

The plan is to detail the main steps, and not every detail of the models construction.

123" wingspan
38-40 Lbs with 150cc Gas RTF.

-Sean

pmmartin

Happy New Year! I am looking forward to this conversion as I really enjoyed the Composite-ARF Extra 330L Conversion. You did a great job and it was a very interesting conversion. Have you had the opportunity to fly the Extra any more?

Sean Plummer

The actual covering and radio install is being performed by Unlimited Aerobatics Pilot and Master Builder Mr. Yuri Higuchi.

Here are the motor details: 4ea. Hacker C50+planetary connected to a belt type gear reduction. The plan is to run each motor at about 65 amps. here is a pic of the motor assembly being test fit.

Sean Plummer

The model incorporates "quick release" latches for both the split cowling and the canopy. Here are the pics of the Cowling hatch release mechanism. also shown is the wood parts that include the motor mount, and cowling frame to support the quick release mechanism.

Sean Plummer

the battery tray is located just below the normal Fuel tank position, and is on the same plane as the motor box, this will allow the batteries to be moved for and aft for C/G adjustment. All parts are made using aircraft and lite plywood. Note: The battery tray is supported at the sides and at the bottom using a brace as shown.

Sean Plummer

The canopy frame is fitted and modified with a "quick release" latch to allow easy access to the batteries. Note: The clear canopy is actually mounted into a fine groove that has been sanded in to the balsa, this will allow for a nearly seamless fit.

Sean Plummer

the model is filled and sanded with 1000 grit paper. The Monokote http://www.monokote.com/ covering as chosen for its easy use and longlasting qualities. Here the parts are getting covered, using paper templates each piece of monokote is hand cut and applied.

Sean Plummer

with the rudder covered the rudder control horn is installed. a Double Carbon pull-pull horn assembly is custom fabricated and installed as shown

Sean Plummer

the fuselage is covered using large strips of monokote. Note: the long pieces curl up after cutting and need to be taped in place prioir to ironing.

Sean Plummer

The lettering for the model is cut out of monokote by hand using templates. Each letter is ironed down one by one. A lot of work but, the result is excellent.

Sean Plummer

Here is Yuri, with the completely covered model. The last steps will be the final motor/battery install and radio setup. These steps will be detailed shortly.

vatechguy3

My Feedback: (11)

any idea as to what the RTF weight will be??

thanks
tony

Bill Mixon

Nice stuff, Sean
Yuri does some really nice building and finish work, as I have seen his other scratch builds. Not to mention he can then take it and fly it through some of the most aggressive "one the edge" maneuvers that you will see.
Is Yuri working on this out in AZ or is it in the northeast region?

GoeKeli

My Feedback: (18)

That is really beautiful! What batteries? Yuri does some amazing work I would love to have a plane he has had his hands on.

Joe

mu2driver

My Feedback: (15)

Hey Yuri hows the Road Rash healing????

Man he is something else...

Gringo Flyer

My Feedback: (18)

Sean, if you dont mind me asking. What does the electric setup with the motors, batteries, etc. run? I would just be curious.

gwright

An old Cliche comes to mind,.. "If you have to ask, you probably can't afford it"

I don't think Sean, and some others do these "standout" conversions to save money, quite the contrary,.. it's much more expensive than gas,.. but it's done to show that the technology is actually there and can literally be used to convert anything, and with increased performance compared to gas/glow. If someone didn't "go out on a limb" and spend the bucks to show what can be done and push the envelope, we wouldn't have developement in these areas like we do.

Gringo Flyer

My Feedback: (18)

Gary, your right I cant afford it. I cant even afford a gas setup for a plane like that. Someone had made the comment to me, ¨I wonder if that electric setup costs more than the gas?¨ The reply was, you better believe it. But seeing as I dont fly electrics I have no idea. I know its not to save money, I was just curious.

I think it is an amazing setup, to think that a 40% plane can fly electric.

pmmartin

I like what Gary had to say. Believe me you could buy a new car for what this cost. It is a marvelous project and really demonstrates the state of the art of electric flying. Not even counting the custom belt drive, which is priceless, this model would cost many thousands of dollars to duplicate. It is much more expensive than gas. It however is the one I would chose if I won the lottery!

Congratulations on a beautiful project guys.

gwright

Assuming they'll be using the acro 90 controllers and 10S3P per motor on batteries, which I believe is correct, each of the 4 "power systems" is roughly $320 for the motor, $420 for the controller, and $680 for the batteries, so $1420 times 4 is $5680, plus the gear reduction (handmade, I can't even guess on that ). A 150 gas setup would be about 1/3 that, but of course performance and flight time would most likely be less with gas.

Bill Mixon

These are just some rough #'s (US) All could vary depending on exactly what is used

Batteries $2720 (this doesn't include the $800+- worth of battery chargers or the power supplies for them)

Motors $1600 (this doesn't include the custom drive)

ESC's $800-1600

So the power system cost would be at least $5000 even if you excluded the drive and other details. Now if I factor in some other prices for other parts of the plane,"WAG" factor the labor and misc cost's it could easily be a $15,000 airplane.

Not cheap be it will be nice. Personally I think the cost of the power system less batteries is fine. I'm willing to pay more for an E powered setup than an IC power setup just because of the reliability and consistency. What hurts is the cost of batteries, as they are a major expense yet they are the consumable part of the investment.

Hannu Vuorinen

Super project, Sean!

Have to you got any motor test run data? How much you got power on shaft?
Is this the same motor seen somewhere earlier in other plane?
I believe this kind of a giant E-power project is allways worth of money invested in it,
testing technical barries is allways challenging. Good luck your project!

BR,
Hannu

famousdave

My Feedback: (61)

MoooHooooHaaaHaaa!! I was lucky today... I caught Yuri and Sean at a valley field by happenstance..won't say where to protect their privacy. The Von Extra a-la-hacker flies!!! Holy SH*T!! Amazing fabrication and covering work by Yuri. Yuri also put on quite a show with his 40% CompARF too...

Very cool.. there was only a few people around.. THAT does not happen often!


I was at Cave Buttes one day a few years ago and Jason Krause (TOC heli pilot) just "showed up" .. I was the only one at the field !

DP

Henke Torphammar

I heard that there is a video of the maiden comeing soon... =)

10kW must sound good in reallity.

fbw4

What an amazing plane! The video is cool but nothing compared to seeing it in real life. Sean is still tweaking the system, so keep in mind that what you see at the [link=http://www.arizonaelectricfestival.com]Arizona Electric Festival[/link] will be even better.

30mb video at:
http://www.rccraze.com/42extra260.mpg