New Product **** GWS-190: Unbeatable Butcher Bird ****

[headlessagain]

You should always balance low wingers inverted
Head

[scousethief]

Hi , cool if i balance the 190 inverted i am pretty much spot on , must be the motor not supplying enough rpm , that's not a problem and easily sorted.

[RCDad]

scousethief, OK, this has gone on far too long.

We need some real numbers so we can come up with good suggestions rather than educated guesses.
Please tell us: The AUW of the plane (including batt), the CG you are flying at, control throws in mm, radio setup, motor size and KV, prop, battery, how are you launching, what is the throttle possition on launch (if by hand), Thrust line of your prop, is the plane lateraly balanced and are there any obvious warps in the wing. Did you make any modifications from the stock setup. I would also like to know the amps and watts you are seeing at 3/4 throttle.

Also: 1) take us step by step how you are launching, what does the plane do, and what inputs you are giving. 2) what is your RC flying experience.

These questions are ment only to help those of us trying help you get a clear picture of what may be happening.

Take care,
Kevin.

Originally Posted by scousethief

Hi , cool if i balance the 190 inverted i am pretty much spot on , must be the motor not supplying enough rpm , that's not a problem and easily sorted.

[scousethief]

motor turnigy 2830
30 amp esc
2200mah batt
9x6 triple prop
coming up to 7 years heli flying.
Plane balances upside down perfectly fine , already had 2 flights pretty much with no problems other than my skill. Esc works perfectly fine when transplanted into my trex so im sticking with a motor problem. ill find out soon as i have a different motor in the post

[57sailplane]

would agree, sounds like you are underpowered.. you do not say what all up weight is.. i suspect this being the culprit. i run the turnigy 35-36 1100kv on mine with an apc 9x6. plane weighs in at 30oz. i had to also shorten nose to balance right. but you can open up battery tray to move battery back more. i have flown mine with a turnigy 3s 4000mah pack moved back, she was a bit heavy but still had plenty of power to fly her. the tgy 35-36 1300kv is my favorite motor for this plane but i was eating batteries.
it had great power and very good flight times actually better then the 1100kv. i will probably be putting that motor back in and limeting my throttle to the proper battery amperage.

later andrew k

[Vintauri]

Is that a GWS 9x6 3 blade prop your using? If so that might be part of the problem. Around here we have found them to be quite out of balance and inefficient. Your also sacrificing speed with the 3 blade prop. You'll often get more thrust for the same power used but loose speed. You might want to try a 2 blade prop to see how that works.

[kensp]

Originally Posted by Vintauri

Is that a GWS 9x6 3 blade prop your using? If so that might be part of the problem. Around here we have found them to be quite out of balance and inefficient. Your also sacrificing speed with the 3 blade prop. You'll often get more thrust for the same power used but loose speed. You might want to try a 2 blade prop to see how that works.

When did GWS start making a 9 x 6 x 3 blade propeller. The last time I looked they had the 9 x 7 x 3 blade RS prop and the 9 x 5 x 3 blade RH or LH rotating props.

The 9 x 7 x 3 blade RS prop is too flexible for use in higher power powered models such as the GWS-190 and the 9 x 5 x 3 blade lacks pitch speed to fly the GWS-190 well. The GWS 3 blade prop to use on the GWS-190 is the 10 x 6 x 3 blade.

I would not recommend using a 3 blade propeller on a model that is hand launched because they have a greater Torque Rolling effect at low speeds and this is not helpfull in the first critical seconds after hand launching.

Ken

[Vintauri]

Your right Ken. They didn't make one. It's been a while since I experimented with them I forgot the pitch. So then I'm also going to ask what make of prop is it. I have not seen many effective 3 blade props unless your willing to sacrifice speed for scale looks.

[57sailplane]

definatly use an apc prop or comparable they are most efficient. i like the Hobby KINg props also.

[kensp]

Originally Posted by 57sailplane

definatly use an apc prop or comparable they are most efficient. I like the Hobby KING props also.

Hobby King have the Turnigy 3 Blade Sport Propellers. These props all have a higher pitch so slower speed may not be such an issue.

Here is the Link http:

When comparing the APC props to the Direct drive GWS Props I found that although the APC props gave around 5% higher thrust they drew more current and ran at a lower RPM. So if you are running a GWS Warbird at close to 1:1 thrust to weight ratio then the extra 5% thrust will not be noticeable in flight but the higher speed and longer duration obtained from the GWS props will be.

My current preferred prop for my GWS-190 is the GWS 10 x 8 HD two blade.

Ken

[RCDad]

scousethief, we need more information:

The AUW of the plane (including batt), how are you launching, what is the throttle possition on launch (if by hand), Thrust line of your prop, is the plane lateraly balanced and are there any obvious warps in the wing. Did you make any modifications from the stock setup. I would also like to know the amps and watts you are seeing at 3/4 throttle.

Also: 1) take us step by step how you are launching, what does the plane do, and what inputs you are giving to counteract the situation.

Originally Posted by scousethief

motor turnigy 2830
30 amp esc
2200mah batt
9x6 triple prop
coming up to 7 years heli flying.
Plane balances upside down perfectly fine , already had 2 flights pretty much with no problems other than my skill. Esc works perfectly fine when transplanted into my trex so im sticking with a motor problem. ill find out soon as i have a different motor in the post

[Condre']

If you are not using the stock motor mount I think this might be caused by insufficient down and right thrust of the motor. Last fall I cracked up my 190 pretty bad. When I put it back together it wanted to turn to the left while rolling off during take off. I kept thinking it was the tail wheel and never sorted out the problem. During its final take off it flipped over to the left and into the ground just as it lifted off. I observed something like this in a video of a GWs 40 that wanted to turn left before it left the ground. Later the pilot said he corrected this by more down and right thrust of the motor.

[57sailplane]

"When comparing the APC props to the Direct drive GWS Props I found that although the APC props gave around 5% higher thrust they drew more current and ran at a lower RPM. "

your rusults are inconclusive. this could mean that the apc prop is less efficient or that it is getting a better bite wich by the more thrust issue i would think it is getting better bite. this would lead to more amp draw and less rpm. in the air this prop will unload and pull probably less amps and provide more speed and thrust..

why, here is my reasoning. coming from the drag racing world i have known for years that one of the largest robing componants is rotating mass. the farther that mass is out from center the more losses occur. if you notice on the gws prop compared to the apc prop its has and equal amount of weight the whole length of the prop so it has more rotating mass at the end creating more losses. secound is that gws wanted to make these props efficent so they copansated by making them lighter. thus if you read the safty limets on this prop it is far below that in rpm of the apc props.. this translates into more flex and distortion. more flex means less pitch and more rpm less thrust and less speed of plane. a good way to really know if you are getting the best out of the right prop. is if it does not make much noise in turns.. if the prop growls like the the gws props do this is power being lost...

but this is only my educated guess.. the only real way to test this is probably to use an eagletree unit in the air which i do not have. or fly each prop with the same flight cracteristics, this is not perfect either as if the one prop flexes more it may become more efficent then the other because it works better with the combo.. motor, plane, kv and so forth. if the this be the case then i would bet that if you replaced the prop that dose not flex with a lesser pitch it would out perform the flexing one.

the other factor is to as which prop the high speed guys would prefer the gws or the apc. they are after speed which you would not think would have anything to do with us foamy fliers. but to get speed you need to be most efficient.. less drag on the fuse, wing winglets and prop.

just my thoughts later andrew k