raflyer

My Feedback: (14)

I have a twin pusher prop Concorde from Dynamic Foamy. 18.5oz 70" long 30"w/s 2 1400kv out runners and a 1200Mah 11.1V 10C lipo GWS 6050 props, watt meter shows this on a fresh charge,

15.6A
173.6W
10.97V

After 20 secs of WOT i get a steady

136W

Correct me if im wrong but at 18ounces and that wattage, shouldn"t this be a fast plane?? It is barely staying in the air! Is it the cheap props?? Thanks for any input

For reference, it is about half as fast as my stock Parkzone T-28

raflyer

My Feedback: (14)

Got a good tip from the wattflyer site , they think i may have my props on backwards. I have the numbers facing the rear of the plane and they should be facing the front or direction of travel. Will try and report back.

speedy72vega

One problem I can see is the discharge rate of your battery. At 10C, it's only designed for 12 amps constant discharge. You stated that the power system is drawing over 15 amps, and you held it for 20 seconds. 20 seconds is beyond whatever burst capacity that battery is capable of, usually 10-15 seconds without damaging it. I would recommend trying to find a battery with at least a 15C discharge rate, and see what your power numbers are. 15C would give you a constant 18 amps discharge, with a burst of probably up to 24 amps for 10-15 seconds. You might be starving your motors of current with that battery you're using.
That's where I would start. You can then experiment with different props, you can try going with smaller diameter props with a higher pitch, that will give you more airspeed and more rpm's at the motors.

Also, make sure that the props are pushers, otherwise the thrust will not be anywhere near what it should be.

speedy72vega

Your props are only going to have one mounting surface. That is the side that has the flat surface that goes against your prop mount. The prop MUST be mounted with this surface towards the motor! That's why there are props specifically designed as pushers. This is very important.

raflyer

My Feedback: (14)

Actually GWS props are easy to mount wrong as the hub is the same on either side, There is no flat side like an APC prop. Never thought installing a prop would be so confusing[&:]

I have a 15C battery i am going to try tomorrow as well. Thanks!

speedy72vega

Really? I've never used GWS props, so I wasn't aware of the mounting surface being the same, I usually only use APC props. I can see how that would be confusing. The only thing I can say is to look at the prop blade. You can usually tell by the shape which side pushes the air, and that's the side that faces the rear. This also may sound stupid, but make sure the motors are turning the right direction also.
Let me know if you see a difference with the 15C pack, i'm curious.