Cobra CM-2206/20 Motor Propeller Data
Magnets Motor Wind Motor Kv No-Load Current Motor Resistance I Max P Max (4S)
14-Pole 12-Turn Delta 2100 RPM/Volt Io = 0.85 Amps @ 10v Rm = 0.065 Ohms 25 Amps 370 W
 
Stator Outside Diameter Body Length Total Shaft Length Shaft Diameter Motor Weight
12-Slot 27.0 mm,  1.063 in. 16.5 mm,  1.102 in. 35.3 mm,  1.390 in. 3.00 mm,  0.118 in. 36.5 gm,   1.29 oz
 
Test Data From Input 6.0 V 8.0 V 10.0V 12.0V Measured Kv value Measured Rm Value
Sample Motor Io Value 0.66 A 0.76 A 0.85 A 0.95 A 2091 RPM/Volt @ 10v 0.065 Ohms
 
Prop Prop Li-Po Input Motor Input Prop Pitch Speed Thrust  Thrust Thrust Eff.
Manf. Size Cells Voltage Amps Watts RPM in MPH Grams Ounces Grams/W
APC 5.25x4.75-E 3 11.1 14.43 160.2 17,849 80.3 466 16.44 2.91
APC 5.5x4.5-E 3 11.1 14.94 165.8 17,747 75.6 481 16.97 2.90
APC 6x4-E 3 11.1 16.38 181.8 17,285 65.5 620 21.87 3.41
APC 7x4-SF 3 11.1 25.33 281.2 14,747 55.9 917 32.35 3.26
FC 5x4.5 3 11.1 8.94 99.2 19,120 85.1 429 15.13 4.32
FC 5x4.5x3 3 11.1 13.43 149.1 18,125 80.7 555 19.58 3.72
FC 6x4.5 3 11.1 16.96 188.3 17,189 76.5 749 26.42 3.98
GemFan 5x3 3 11.1 6.74 74.8 19,714 56.0 381 13.44 5.09
HQ 4x4.5-BN 3 11.1 8.69 96.5 19,260 85.7 353 12.45 3.66
HQ 5x3 3 11.1 5.09 56.5 20,450 58.1 291 10.26 5.15
HQ 5x4 3 11.1 8.73 96.9 19,175 72.6 445 15.70 4.59
HQ 5x4.5-BN 3 11.1 13.92 154.5 18,180 80.9 572 20.18 3.70
HQ 6x3 3 11.1 8.78 97.5 19,261 54.7 495 17.46 5.08
HQ 6x4.5 3 11.1 16.98 188.5 17,233 76.7 762 26.88 4.04
HQ 6x4.5x3 3 11.1 21.27 236.1 15,917 70.8 844 29.77 3.57
HQ 7x4-SF 3 11.1 25.30 280.8 14,772 56.0 942 33.23 3.35
 
Prop Prop Li-Po Input Motor Input Prop Pitch Speed Thrust  Thrust Thrust Eff.
Manf. Size Cells Voltage Amps Watts RPM in MPH Grams Ounces Grams/W
APC 5.25x4.75-E 4 14.8 21.87 323.7 21,797 98.0 692 24.41 2.14
APC 5.5x4.5-E 4 14.8 22.55 333.7 21,573 91.9 716 25.26 2.15
APC 6x4-E 4 14.8 24.48 362.3 20,848 79.0 912 32.17 2.52
FC 5x4.5 4 14.8 13.65 202.0 23,732 101.1 685 24.16 3.39
FC 5x4.5x3 4 14.8 20.00 296.0 22,341 95.2 845 29.81 2.85
FC 6x4.5 4 14.8 24.86 367.9 20,696 88.2 1114 39.29 3.03
GemFan 5x3 4 14.8 9.61 142.2 24,158 68.6 587 20.71 4.13
HQ 4x4.5-BN 4 14.8 12.61 186.6 23,927 102.0 549 19.37 2.94
HQ 5x3 4 14.8 7.82 115.7 25,301 71.9 465 16.40 4.02
HQ 5x4 4 14.8 12.98 192.1 23,857 90.4 695 24.52 3.62
HQ 5x4.5-BN 4 14.8 20.40 301.9 22,356 95.3 857 30.23 2.84
HQ 6x3 4 14.8 13.99 207.1 23,658 67.2 818 28.85 3.95
HQ 6x4.5 4 14.8 24.18 357.9 21,021 89.6 1100 38.80 3.07
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, at an altitude of
512 feet above sea level.  The test voltages used are based on the standard output of a Li-Po battery under load, which is 3.70 volts
per cell.  If you are using a battery that is larger in capacity than normal, or has a very high C-rating, then your actual voltages will
be higher than those shown in the chart, and this will result in a higher current and power value for every prop used.  You should
always test your actual power system with a watt meter before flying your model to make sure that you are not exceeding the 
recommended current and power ratings of the motor being used.  The prop recommendations in this chart assume that the motor
receives adequate cooling throughout its operation.  If your motor is being used inside a cowl or fuselage, you must ensure that
the motor receives sufficient airflow, and does not get too hot during operation.  It is always best to use a prop size that pulls no
more than 80% of the motors maximum recommended current value to ensure safe operation under all conditions.