Flight Issues

[Raiyan]

Hello. I'm having some problems flying my scratch built plane. I'm using a Turnigy Air 1350kv brushless outrunner motor and I'm not sure what size propeller to use with it. I've tried a few but I don't get enough thrust for any vertical performance. It barely flies. I haven't gotten any more than 10 seconds of flight and I can't get the plane to climb. Someone please help.

 

[Craftydan]

Raiyan,

welcome to the forum!

We'll need more details than that.

I'm assuming you mean this motor:

http://www.hobbyking.com/hobbyking/store/__14739__turnigy_l2205_1350_brushless_motor_100w_.html

What airframe are you flying? What's the All-Up Weight (AUW)? What size/voltage battery are you using?

Pictures or video would be very helpful.

BTW, Vertical perfomance isn't necissary for fixed-wing aircraft -- in fact if you're short on experience the extra power may get you into trouble far faster than it will help get you out -- but that motor would have to be pulling a pretty light/small airframe to have any vertical acceleration.

 

[Balu]

Also make sure the prop is the right way round. Usually it has small numbers written on it, they have to be in front.

If they are and the plane moves backwards you need to reverse the direction of the motor

 

[Raiyan]

Yes, that is the motor I'm using along with a 25amp esc and the battery in the link below.

http://www.hobbytech.com.my/detail_generator.php?cat1=LP&code=LP0037

Here are the pictures of the two frames I've made so far.


Could you suggest me some airframes I could build with my current setup?

 

[IFlyRCstuff]

Is it lack of power, or what?? If you still want a prop recommendation 8x4e has always served me well on similar motors. Have you done a full on inspection of the motor?? Check the stator wiring and all the other lovely stuff. I would try to swap motors, put another one with simlar kv/watt rating and the same prop see if that will do anything. If not, you may have a bad esc.

 

[Craftydan]

Riyan,

nothing obvious stands out, but it's hard to tell.

With the battery installed how heavy are the airplanes?

What battery are you using?

 

[Raiyan]

My setup seems fine. Everything works properly. I'm just not being able to get the lift that I need. It's probably too heavy. Can you suggest me some good airframes that i could build? Would the Simple Soarer be a good plane to start with? I've got my eye on the Storch. It would be very helpful if you could give me some suggestions on that. Thanks Dan

 

[Balu]

What I've read so far is that the Storch seems to be an amazing plane for the whole spectrum from beginner to advanced. It started as the "FT Trainer" and was modified into a Warbird to fit into a series.

 

[Craftydan]

That motor powered by a small-to-medium 3S pack will be on the light-powered side for a storch, but yes, flyable. It'll be a touch underpowered, but so long as you don't try to fly it crazy it'll be a slow happy plane. If you're new to flying, it might be a little too light on power for learning a "full house" plane (throttle, elevator, ailerons, rudder), but it's doable. If you go this route, I'd focus on coordinating rudder and aileron in flight, managing the throttle and flying the pattern (down the runway, gentle turn around, back down beside the runway gentle turn back).

For the simple soarer, if it can fly without a motor, a nice lightweight motor like that one will do just fine . . . 2S or 3S, so long as the battery is on the light side and you can get the balance right. *Be sure to turn the brake on in your ESC* Two words of caution:

- take your time building the simple soarer. It has a lot of long joints that are easy to get a subtle twist in. Gliders are particularly sensitive to defects in building. It will still fly if it's not perfect, but the closer you get to perfect will show in flight. Take your time, watch the video a time or two and stop to look at the parts as it comes together to make sure everything stays alligned as best as you can.

- Powered gliders are designed to glide. the motor on the front is there to bring it to altitude and you ride it down unpowered looking for any lift you can find on the way. they're usually trimmed so they nose up and climb under power and can be a bit of a handfull to control while powered, and as placid as a calm lake in a glide. You can run it up at low power and cruise around like a park-flyer, and probably for a really long time, but it'll never perform like a 3D plane, or a pylon racer. If you go this route, enjoy her for what she is

 

[kingbee]

Raiyan

welcome to the forum . well looking at you first model it look alot like a cub ,and i see why it not flying well .it is because the angle on you back tail is not inline with your wings . look at the body frame and you see it goes up and not in line with the rest of the body. correct that and check your cg . make sure your angle of dihedral on your crosswings are ok .cause it will pull to the left or right . good luck .

 

[Raiyan]

Thank you so much. I've completed the simple soarer. Ready for a maiden flight. It's not perfect though. I'm having trouble building the fuselage. I've made some modifications to get it done but the elevators aren't aligned with the wings. The angles seem to differ. Will it have too much of an effect or will i still be able to fly it? I ordered a 9x4.7 propeller and once it's here I'll go for the maiden. Got my fingers crossed. I hope it works this time or I'll just order a speed build kit for the Storch. Cutting foam isn't probably my strong point.

I also ordered this motor along with a 40amp ESC. Perhaps I can use that setup on the Storch.
http://www.hobbyking.com/hobbyking/store/__16229__ntm_prop_drive_series_28_30a_750kv_140w.html

 

[IFlyRCstuff]

The angles (if you mean side to side/horizontal angles) should be perfected, it will fly, but the elevator will act as rudder if it is more than about 3 degrees off, even then. If you mean vertical, the entire stabilizer will act as an elevator, try cutting into the foamboard to make it a even surface, also check that the wings are even if that is what you are comparing it to.