wingspar

My Feedback: (3)

I posted this in the electronics forum but didn't get much of an answer so I thought I'd try here.

I'm drawing up a plan for a 1/4 scale P-39 but can't get the engine cylinder enclosed so I'm thinking of trying an electric motor. Possible the Turnigy 80-100-A 180Kv Brushless Outrunner which is equivelent to a 60 to 80cc engine. Gear will be Sierra assuming Darrell will make them for me. Start time would be next fall after my 190 is finished.

Has anyone done this successfully?
How was the performance as compared to using an gas engine?

Dave

BigRetracts-RCU

Dave,

I am sure it would work great. (Athough pretty pricey)
If you really want a scale look, design it with a belt reduction
unit and use a scale size 3 Blade Solo Prop Hub and Blades.
Now that would be cool!

Darrell

Evil_Merlin

My Feedback: (13)

What Darrell said. I've only seen one larger scale plane running on electrics. And it was "only" an 85" wingspan.

Something that big is going to need one hell of a engine, and a bunch of batteries, not to mention a massive speed controller. I would also have doubts about using a bargin motor for your big plane.

I've seen SOME of the 3D pilots flying bigger birds around 25-30 lbs with these and using 12S 2P 5000mAh, lucky to get 7 minutes of flight time.



If going electric, I would pass on the cheap motor and go with the Hacker A60-18L and make sure you get a decent power supply.

Its going to be more expensive than a good gas setup, weigh more overall and have less of a flight time on it.

wingspar

My Feedback: (3)

Maybe this just isn't practical.

Evil, I looked up the hacker motor and it is rated at 2600 watts. The Turnigy is rated at 7000 watts. nearly triple the power. I don't know if this motor is any good or not. Reading reviews most people seem to like it.

My choice would be to use a gas enigne but I don't want it stick out. I don't even like servos sticking out on scale models but that's just me.

Darrell, I agree with you but don't know of anyone making the reduction drive for this large electric motor. I need to do more research.

Dave

Ram-bro

My Feedback: (101)

what ever you figure out let us in on the decision. I have a 85" set up on electric and wantto go larger some day

LDM

My Feedback: (15)

Its practicle but you have to think out of the box -defined as non-traditional building materials .
I would consider , carbon fiber rods , foam , ect .
I have seen a 1/5 foam russian fighter on RC groups , blue foam , will rival a top gun plane in detail , all eletric , incredible plane . If i can find the link I will post it

vik

My Feedback: (1)

I would more consider Hacker A80 series for such application.
For 2m class there is quite popular AXI 5345/18
If you want to go with Turnigy, please refer to Mick Reeves spitfire page.
There is 1/4 Spitfire from english gentleman running 20S pack (serial and paralel 5000mAh packs)

The main question is the weight

Walt Thyng

My Feedback: (9)

I've been flying a 1/4 scale (105") Nosen Citabria with e-power for over 10 years. Started with a geared Astro 60. performance was very scale-like (read not too overwhelming). I currently have a True R/c outrunner of unknown specs spinning an 18/6 pattern prop running on a 10S, 6000 mah Lipo and a CC 85HV esc. Weight is 17lbs RTF. Will do over 400 feet of vertical from level flight. Duration varies from 7 mins of full out aerobatic flight to 12 mins of mixed sport flying with plenty of reserve for missed approaches.

The reason the 3D guys get so little duration is that they are pushing their power systems to the limit for the entire flight.

I also fly a 1/4 scale Forbes F2 Cobra racing biplane. Top wing is 76", bottom. 60"; weight 16lbs (I purpose built ti for e-power and brought it in right at the lower projected weight of the plans). It is powered my a MaxCim MegaMax, a CC 85HV esc and 10 Lipos (same pack as the Nosen). Flight times are right at 10 mins with reserve. It has been clocked on radar at 90+ mph. since the full scale had about a 200mph top speed, is is nearly twice the scale speed.

I will fly any airplane up to 30 lbs on e-power; after that my wallet runs out (-:
Walt

wingspar

My Feedback: (3)

Wingspan would be around 102 inches and weight around 40 lbs. The motor and controller are around $400 dollars. The new V2 version of this motor appears to be well received.

Not having alot of luck finding a reduction drive for anything near this motor. Maybe one of the reduction drives for gas engines could be modified and made to fit. Sure would be great to swing a three blade Solo prop.

Dave

race44

My Feedback: (6)

Hey WingSpar, I built a P63 with a 100 inch wing, which is 22%. I had an extension made by Russel Stoltz who makes the Husky engines. It was 17 inches long and it put the fire wall back to the leading edge of the wing. I incorporated the front wing hold down with fire wall. The front nose ring was aluminum and was attached to the nose ring of the Fiber glass and Epoxy fuse of the 63. The tube that housed the drive shaft attached to the engine and bolted to the aluminum nose ring and had a good size double bearing installed in the nose end. Since it was a Race Plane for the Unlimited Air Races, I used A Husky Challanger 200 cc inline twin that Russell builds. I'm like you, I have only a wire 1/2 inch long that turns on the radio, and thats all that sticks out of my stuff no servos sticking out ect. It was an awesome plane and nothing was sticking out. The fuse was big enough back at the leading edge, (about 10+ inches) to have the exhaust inside and the 2 carbs and all of the engine. I brought it to Reno Nevada for an Unlimited race, and won a Futaba Radio and a Pair of tickets to the next race with pit passes, for the highest degree of engineering for a Racer. The 63 actually balanced out, well what I call balanced out anyway, I like the nose to drop on the runway ( instead of adding lead ) when you hold the wings at the CG point. The rules for a scale Racer in the unlimited are quite simple.... 55 LBS Dry, and a max weight of 14 LBS of engine ready to fire. The extension was perfect the vibration was absent with the twin and it ran sweet. The weight of the engine was around 12 LBS and the extension was 5 LBS. I over engineered the whole plane ( I was young and Dumb) and it hit the scales at 55 lbs. with the clipped 77 inch wing. With the extension being only 2 inches in diameter, allowed room for a nice nose wheel gear from Robart. There is no room for a nose gear with an engine up in the nose which uses a 4 inch Tru-Turn spinner at 22 % scale and no air intake under the spinner like a Mustang ect. It is an easy thing to put together and you have your engine back like the full scale 63. Because the wing on the 39 and 63 are so close to the center of the fuse it forced guys into too small of an engine so balancing would be possible. I have drawings for the contraption and would share. There is no center mounted engine on a 39 or 63 that I know of. I make the 100 inch 63 or 39 fuse and have a Laminar flow airfoil on my wing cores. The Racer I am talking about, snap rolled on take off when the pilot let her roll out for a few seconds not knowing he was doing nearly 70 MPH when he horsed it up. The Challenger 200cc twin was spinning a 22x24 pitch blade at around 8200 static. I love the King and the Cobras and am thinking about a mid belly installation with the engine behind the driver. It would surely garner 1st place in a scale Warbird event. Tha'ts my 2 cents worth.......Dick....PS Here's some shots of my 63 with a Herby in it, and a shot of the inline in my Stiletto, I cant find my inline set-up in my 63 right now......Dick

Walt Thyng

My Feedback: (9)

down load Drive Calc. It is a free on-line predictor program. Take a couple of hours to learn how to use it, then program in your parameters and it will give you a darned good idea of what kind of performance you will get wiht various motors, props, batts etc.

By the way my Nosen uses and 18/10 prop, not 18/6.

Outrunner motors have become so popular precisely because they don't need gear boxes to swing large props. Drive Calc will tell you how big you can go for a given motor/battery combo.

I haven't looked up the motor you specified, but the lower Kv the better for your app.
Walt

JeffH

My Feedback: (43)

http://www.aero-model.com/Hacker-Brushless-A200-8.aspx

one of these will swing a 30" 4 blade around 5000 rpm at 200 amps on 14s 13,500Mah setup. There is a 1/4 scale Spitfire build on RCSB that detailed this setup.

fockewulf37

My Feedback: (102)

A buddy of mine has this motor...

http://hobbycity.com/hobbyking/store...idProduct=5140

They are running a 21x10 at 9000 rpms (32lbs static thrust) on a 12 cell pack. They pulled back the throttle settings where it would drop back to 7000 rpms on a 23lbs topflight p-47.

This motor pulls stronger than the 80-100 they sell. They had a 24x10 prop and it was just way too much... I would consider replacing the beerings though ....

Ty

Ron101

My Feedback: (22)

All I fly is large scale electrics. I have a few of the smaller turnigy motors and many of the guys at the field love them. With that said many have demaged or threw magnets.

I have a bunch of Hacker motors and Neu motors... that is hands down your best bet. In a project like this I wouldn't mess with those cheap motors

I ran a Neu motor geared inrruner in my 30% extra - 1521 1.5 y with a 24x14 prop it had 4600 watts in a 17.5 pound plane on 12s 5000 mah
unlimited performance with over 260 watts per pound...it makes a DA-50 look silly

I'm now trying a Hacker A-60 18L and it also has great power! right around 4000 watts

I have a bunch of Nue motor and Hackers I would run them hands down in this project.... with hyperion packs

I would run the Hacker A80-10 on 12s 35c 10000 mah packs it will turn a three blade with no problem

another great light option which would fit nice and easy would be the Neu 2215/2y with the HD 6.7:1 gear box... you will turn a huge three blade with this. At 40 pounds ready to fly you are going to need 6000 watts that will give you 150 watts per pound which is perfect for a warbird. At 6000 watts your going to be pushing 135 amps so you will need a good Castel 160 Hv or a Spin 200

you may get by with cheap hobby king packs if you run four 6s 5000 mah pack with two 6s 5000 in series to make one 6s 10000 mah then in series with the other two packs to make 12s 10000 mah.
with that high of a mah number you will get a good flight time and even 30c packs at 10000 mah will be good for 350 amps cont.

It would kick but electric

JeffH

My Feedback: (43)

Ron 101, what motor would you recommend to turn a 24-26" 4 blade? I want to run a decent sized 4-blade on my 1/5th scale Mustang and Spitfire.

Ron101

My Feedback: (22)

That big of a four blade it going to take big power to fly well.
I'd use the same pick as above to turn that.

Hacker A80-10 or the Neu motor 2215/2y with the HD 6.7:1 gear box

Run 12s 35c 6500 mah Hyperion G3 packs with a Castel Creation 160 HV

it will make those old bryon four blade reduction look like there sitting still

nither are cheap, but they are the best, you get what you pay for.


In my 1/5 P-51 I went with a lighter setup, but it won't turn a four blade. I'm running the AXI 5345-14 on 12s 35c 6500 mah hyperion G-3 with a 21x14 APC E prop
should put me in the 135 mph range. Hope to fly it soon.

wingspar

My Feedback: (3)

Thanks for all the great suggestions.

I really like that hacker A200-8 link that Jeff sent. Might be a little to much motor for this plane.
Another guy sent me a link for the Turnigy CA120-70 Brushless Outrunner. It's equivelent to a 100CC motor which would be ideal. From the pics it looks well made.

What about cooling on outrunner motors? Do they have an internal fan as the spinner would block the front of the motor. Possibly a water jacket around the motor if needed?

Looks like this is possible and I'm going to finish the drawings on the plan.

Dave

curtusua-RCU

My Feedback: (91)

[quote]ORIGINAL: Ron101


you may get by with cheap hobby king packs if you run four 6s 5000 mah pack with two 6s 5000 in series to make one 6s 10000 mah then in series with the other two packs to make 12s 10000 mah.

Hi Ron...

I think you meant to say to run each of the two 6S 5000 packs in *parallel* and then to wire those two 6S 10000 mah packs in series to make a 12S 10000 mah system.

I fly all big electrics too... looking forward to your P-51 flight report.

Curt

Ron101

My Feedback: (22)

http://www.aero-model.com/Hacker-Air...lbs-50lbs.aspx

hacker motors are way underrated on there watts... you don't need the 200.
I'd go with the A80-10 the A100-8 at the very most... to me it's just added weight and cost.

the nue motor is going to be the lightest most powerful setup you can pick

here is what I'd run: http://www.espritmodel.com/index.asp...OD&ProdID=4637

over kill: http://www.espritmodel.com/index.asp...D&ProdID=12703

http://www.neumotors.com/Site/2200_series.html


The Neu motors are just bullet proof....

Ron101

My Feedback: (22)

Thanks Curt that's what I meant... it's harder to type this stuff than do it sometimes

two 6S 5000 packs in *parallel* and then to wire those two 6S 10000 mah packs in series to make a 12S 10000 mah system ... thats what you need

And I wouldn't be afraid of cheap hobby king packs at this high of a mah.

four of these will do the job just fine:

http://www.hobbyking.com/hobbyking/s...0mAh_6S1P_30C_

or these

http://www.hobbyking.com/hobbyking/s..._30C_Lipo_Pack


I still only run hyperion G3 and Thunderpower 30c or 40c packs in my big stuff , but I have many smaller hobby king packs and they work fine.

great packs: http://www.espritmodel.com/index.asp...D&ProdID=10661

the best: http://www.espritmodel.com/index.asp...D&ProdID=11418

Evil_Merlin

My Feedback: (13)

Ron, a 17 lb plane isn't exactly a big plane... and most people flying a 17lb plane are not going to be doing it with a 50cc motor either...

Ron101

My Feedback: (22)

I was just giving him some of my back ground, the motors I recommended for him are not what was used on that plane. Mine is a 3D 30% extra so it's as big as a 1/5 scale warbird, 90 inch wing span.
You are wrong about guys not flying a 30% plane with a DA 50, in fact 30% planes are called 50cc by most.. But this is 3d stuff.
I fly with a bunch of guys that fly this same size plane with a DA 50 and my eletric setups make the DA 50 look like a toy.... much more power.. it pulls out of a hover like crazy.

I'm building a 1/5 scale mustang which is almost done, for electric power, I have two 60 sized warbirds for elelctric power

I have also built and flown a Tam Jets A-4 electric, Cermark F-16... I'm building a Jet Legend 1/6 scale Hawk EDF and a Huge Yellow Twin F-18 Twin EDF

So sharing some of my background was to let him know I have an idea of what I'm talking about, that was all

Evil_Merlin

My Feedback: (13)

Yeah there is a huge difference between the 3D birds and the Warbirds. I assumed since we were in the Warbird section that is what you are talking about.

Most of my 1/5th scale stuff is over 20lbs and averages 82" wingspans.

Ron101

My Feedback: (22)

There is a huge differance, but not in the motors that fly them. 3D you use a DA 50 in a 17 pounds plane , with a warbird you could fly a 25 pound plane fine with that.
The point was the electric has much more power than the DA 50, so it will fly a 25 pound warbird better also. We were talking about power setups so I was giving the guy an idea about different setups.

I flew gaint scale gas warbirds for many year also, been flying for 17 years, so have a good idea of what I'm talking about.

Evil_Merlin

My Feedback: (13)

I've been flying giant warbirds for 20+ years.

I still don't fly them with electric.