Cobra C2808/26 Motor Propeller Data
Motor Wind Motor Kv No-Load Current Motor Resistance I Max P Max (3S)
26-Turn Delta 1130 RPM/Volt Io = 0.75 Amps @ 10v Rm = 0.075 Ohms 22 Amps 240 W 
 
Outside Diameter Body Length Total Shaft Length Shaft Diameter Motor Weight
35.0 mm,  1.38 in. 28.1 mm,  1.11 in. 48.0 mm,  1.89 in. 5.00 mm,  0.197 in. 80.5 gm,   2.85 oz
 
Prop Prop Input Motor Watts Prop Pitch Thrust  Thrust Thrust Eff.
Manf. Size Voltage Amps Input RPM Speed Grams Ounces Grams/W
APC 8x4-E 11.1 10.14 112.5 10,196 38.6 665 23.46 5.91
APC 8x6-E 11.1 14.62 162.3 9,482 53.9 763 26.91 4.70
APC 8x8-E 11.1 18.79 208.6 8,824 66.8 680 23.99 3.26
APC 9x4.5-E 11.1 13.92 154.5 9,591 40.9 906 31.96 5.87
APC 9x6-E 11.1 15.96 177.1 9,264 52.6 901 31.78 5.09
APC 9x7.5-E 11.1 21.71 241.0 8,285 58.8 876 30.90 3.63
APC 10x5-E 11.1 18.74 208.0 8,807 41.7 1097 38.70 5.28
APC 10x6-E 11.1 20.14 223.6 8,566 48.7 1128 39.79 5.05
APC 10x7-E 11.1 22.34 247.9 8,145 54.0 1148 40.49 4.63
APC 11x5.5-E 11.1 23.63 262.3 7,909 41.2 1317 46.46 5.02
 
Prop Prop Input Motor Watts Prop Pitch Thrust  Thrust Thrust Eff.
Manf. Size Voltage Amps Input RPM Speed Grams Ounces Grams/W
APC 7x4-E 14.8 10.91 161.5 13,762 52.1 783 27.62 4.85
APC 7x5-E 14.8 13.95 206.4 13,216 62.6 799 28.18 3.87
APC 7x6-E 14.8 14.62 216.4 13,085 74.3 868 30.62 4.01
APC 8x4-E 14.8 16.22 240.0 12,806 48.5 1074 37.88 4.48
APC 8x6-E 14.8 23.09 341.8 11,562 65.7 1162 40.99 3.40
APC 9x4.5-E 14.8 21.87 323.7 11,770 50.2 1433 50.55 4.43
Propeller Chart Color Code Explanation
   The prop is to small to get good performance from the motor. (Less than 50% power)
   The prop is sized right to get good power from the motor. (50 to 80% power)
   The prop can be used, but full throttle should be kept to short bursts. (80 to 100% power)
   The prop is too big for the motor and should not be used. (Over 100% power)
PLEASE NOTE: 
The data contained in this prop chart is based on actual measurements taken in a controlled test 
environment.  The test voltages used are based on a properly sized Li-Po battery for the current
draw of the motor being tested.  If you are using a larger than normal capacity battery, or a very
high C-Rated battery, your actual voltages will be higher than those shown in this chart, and this
will result in higer current draw for each prop used.  You should always test your power system
with a watt meter whenever a prop is used to ensure that you are not exceeding the recommended
rating of the motor being used.  The prop recommendations in this chart are based on the motor
receiving adequate cooling throughout its operation.  If your motor is being used inside a cowl, you
must provide adequate cooling to the motor and make sure that the motor is not getting too hot
during operation.