View Full Version : Hangar 9 or Graupner AT-6 Texan ARF??
Which of them do you guys think is a better ARF kit? Im planning to use a AXI 4130-16 with a BalancePro pack 8S2P 4000mah running an APCe 14x7 that draws 43amps and delivers 1100watts at 8700RPM. This will result in about 120watts/lbs.
Do you guys think this is a nice power system? I dont want to go above 43amps so I can keep my 15C battery pack in good shape.
Thanks a lot
06-06-2006, 01:43 AM
I'd say the Hangar 9 ARFs are the best around. Graupner is pretty good as well. It would probably come down to color scheme if I were going to buy one. The H9 Arf is listed as 7.5-8 lbs RTF. I'd go for the lightest one if I couldn't choose by color scheme.
8 cells is pushing the 4130/16 a little hard. Most people I've seen are flying the AXI 4130/16 with a 15x10 prop and drawing about 45 amps static. I can't imagine what the motor would draw on an 8 cell pack with a 14x7 prop. Whatever you do, make sure you use a meter and measure the static amp draw.
06-06-2006, 02:12 AM
With a 14x8 MAS, I was pulling around 50 amps static in the Lancair from GP. This was with a 8s PQ3700. With good cooling it never felt very hot after a flight. I would reccomend the 6s and a larger prop to save some weight but the 8s will make it realy move!
Here is the problem:
I have a BalancePro pack 6s2p 4000mah rated at 15C, and I choose to limited at 42amps max continuos for maximun pack life. When I run PCalc with an AXI 4130-16, a 15x10 prop and my battery pack I can get 42 amps, but only 860 Watts.
Since Im looking for at least 1100 watts, I thought the only way I can reach that is by adding a 2s2p 4000 pack, making an 8s arrengment. And again if I run PCalc with this arrengment and a 14x7 prop I can get 43 amps and now 1181 Watts.
Im I right? Since Im new to electrics I would really apreciate your oppinions.
06-06-2006, 03:58 AM
If you come out at the advertised 7.5lb weight (I can't imagine why you wouldn't with lipos) You'll have plenty of power for anything you'd want to do in a Texan.
I have a 9 lb Me-109 that flys great with an E-Flite Power 60 and an APC 15x10 E prop. It's virtually identical to the AXI 4130/16. I'm using four 3s TP 2100 PLs and a Phx 60 controller. It won't do 3D but I can get 10 minutes of way above scale performance. The combo I'm using is drawing 45 amps static and spinning the 15x10 prop at 6900 RPM (directly measured) . That gives the model over 160 ounces of static thrust and a pitch speed of 66 MPH.
I wouldn't sweat the difference between 42 and 45 amps. Your cells should be able to deliver 60 amps continuous, 45 is still very conservative. The batteries will get plenty of cooling in the cowl. I'd make sure to have a good sized exit hole, though.
Are you looking for more power than this?
What I have in hands now is a AXI 4120-18, and my BalancePro 6S2P 4000mah pack. Im finishing a Great Planes Big Stick 40 and Ill use this power system on it. Im sure Ill have plenty of power for the stick, but Im not sure for the AT-6 that im planing to buy.
Since Im getting some real different numbers from PCalc and Motorcalc Ill quit using the computer and start doing some static tests since I dont know for sure how many watts can this system deliver. If I can get at least 950watts, that will give me around 110watts/lbs (The graupner weight will be 8,6lbs with my power system) what I think is ok. And if the H9 is lighter than that Ill have an even better performance and no need to buy another motor and battery pack.
06-08-2006, 05:57 AM
The 4120 is a little marginal for an 8 lb model. But it's certainly capably of flying an 8 lb Texan.
If you get closer to 9 lbs, you'd be better off selling/swapping the 4120 and get a 4130/16 (or E-Flite Power 60) The thing is you're going to have to fly with a smaller prop to stay within the limits of the 4120/18 motor. Probably a 13x8 prop. That means you're going to have to keep the RPMs up and battery economy may not be as good as with the 4130 series.
You will probably need all the weight you can get up front since the Texan had a short nose due to the radial engine. How much weight you will need depends on how heavy the tail has been built. But going with a heavier motor is a good way to add weight.
A guy at my field has a 4120/18 in a .40 sized Corsair. It goes ballistic but I wouldn't want to fly it with another pound or so added on.
If you have a tach and watt meter you can get very accurate performance specs. With measured stats the guess work is eliminated.
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