|Feb 29, 2012, 08:28 PM|
need advice. prop for large scale electric warbird.
I just ordered the new ESM Texan II from Troybuiltmodels.com
80" wingspan, in the range of 18-21 lbs AUW.
Another RCG member electrified the ESM Hurricane, which is roughly the same size and weight with an E-Flite Power 160 on 12s 5000.
Since I have a handful of 12S 5000 packs, Im going 12S as well, and my motor choice was the Monster Power 160. My esc is undetermined yet.
However, I want to run a 4-blade prop. SInce this is setup for gas, they recommend an 18x10 4-blade.
Im not sure:
a.) what size prop to go with
b.) what ESC (leaning towards a CC 120HV)
Thanks in advance for any advice.
|Mar 11, 2012, 10:56 AM|
Due to motor spec. of the eflight power 160 the max continous current is 60 A. With a 17.3x8 4-blade, or 18x10 4-blade the motor current
is too high. I would try an apc 16x10 or 16x12 2-blade prop. The prop efficiency of a 2-blade is also much higher compared to a 4-blade prop.
Maybe you can find a 15x10 or 15x12 3-blade prop.
|Mar 12, 2012, 02:30 PM|
The pitch speed with a 16x8 4blade is maybe too low for your Texan II. I have calculated a speed of
22 m/s of your Texan II, horizontal flight. If the 16x8 4blade is to slow use e.g a 15x10 4blade prop.
Motor and speed calc see:
|Mar 12, 2012, 03:08 PM|
Im getting a little higher numbers from ecalc...around 64mph pitch speed.
However, Im taking your advice into consideration... a 15x10 does produce some sweet numbers.
I can drop it down to 10S and still pull 300oz of torque and 74mph
Menz makes a 15x10 4 blade. I'll try it out.
|Mar 12, 2012, 03:56 PM|
My drive calculation as well as others is a point of start. Due to variation of prop, lipo and motor data it is
only a means to start. I would also use a watt meter to check the current/power.
Next point is than to see the performance during flight.
In the attachment i have a rough way to calculate the power needed to lift a model.
|Category||Thread||Thread Starter||Forum||Replies||Last Post|
|Help!||landing gear on an fpv radian. need advice. ne1 try it?||g3f0rc3||FPV Talk||5||Feb 28, 2012 12:48 AM|
|Discussion||New to large electric models, need advice||Raymond_Gaskins_||Giant Electric Planes||6||Dec 04, 2011 11:06 AM|
|Discussion||New to RC ...and need a little advice with Honey Bee||imortal98||Beginner Training Area (Aircraft-Electric)||10||Nov 15, 2011 08:50 AM|
|Help!||Need opinions on motor and battery for large electric.||haasjj||Electric Plane Talk||13||Sep 24, 2011 03:19 AM|
|Discussion||Need LARGE electric model advice||oldeflyer||Electric Heli Talk||18||Jan 30, 2008 11:23 PM|