Cobra CP2814-1050 Motor Propeller Data
Magnets Motor Wind Motor Kv No-Load Current Motor Resistance I Max P Max (6S)
14-Pole 13-Turn Delta 1050 RPM/Volt Io = 2.06 Amps @ 15v Rm = 0.034 Ohms 48 Amps 1065 W
 
Stator Outside Diameter Body Length Total Shaft Length Shaft Diameter Motor Weight
12-Slot 35.1 mm, 1.38 in. 36.0 mm, 1.42 in. 41.5 mm, 1.63 in. 5.00 mm, 0.197 in. 120 gm, 4.23 oz
 
Test Data From Input 12.0 V 15.0 V 18.0V 21.0V Measured Kv value Measured Rm Value
Sample Motor Io Value 1.774 A 2.058 A 2.196 A 2.645 A 1086 RPM/Volt @ 15V 0.0340 Ohms
Prop Prop Li-Po Input Motor Watts Prop Pitch Thrust Thrust Thrust Eff.
Manf. Size Cells Voltage Amps Input RPM Speed Grams Ounces Grams/W
APC 8x6-E 3 11.1 21.73 241.2 10,800 61.4 995 35.10 4.12
APC 8x8-E 3 11.1 29.66 329.2 10,329 78.3 936 33.02 2.84
APC 9x4.5-E 3 11.1 20.09 222.9 10,906 46.5 1200 42.33 5.38
APC 9x6-E 3 11.1 24.29 269.6 10,648 60.5 1201 42.36 4.46
APC 9x7.5-E 3 11.1 36.12 401.0 9,950 70.7 1295 45.68 3.23
APC 9x9-E 3 11.1 41.77 463.6 9,614 81.9 1264 44.59 2.73
APC 10x5-E 3 11.1 28.90 320.7 10,383 49.2 1522 53.69 4.75
APC 10x6-E 3 11.1 32.93 365.5 10,148 57.7 1594 56.23 4.36
APC 10x7-E 3 11.1 37.82 419.8 9,871 65.4 1656 58.41 3.94
APC 10x8-E 3 11.1 41.66 462.4 9,695 73.4 1716 60.53 3.71
APC 11x5.5-E 3 11.1 39.99 443.9 9,707 50.6 2069 72.98 4.66
APC 11x7-E 3 11.1 46.49 516.0 9,263 61.4 2112 74.50 4.09
APC 11x8-E 3 11.1 50.95 565.5 8,934 67.7 1914 67.51 3.38
APC 12x6-E 3 11.1 50.01 555.2 9,000 51.1 2425 85.54 4.37
 
Prop Prop Li-Po Input Motor Watts Prop Pitch Thrust Thrust Thrust Eff.
Manf. Size Cells Voltage Amps Input RPM Speed Grams Ounces Grams/W
APC 7x6-E 4 14.8 21.01 311.0 14,727 83.7 1098 38.73 3.53
APC 8x4-E 4 14.8 24.07 356.2 14,508 55.0 1386 48.89 3.89
APC 8x6-E 4 14.8 39.61 586.3 13,428 76.3 1579 55.70 2.69
APC 8x8-E 4 14.8 49.16 727.5 12,781 96.8 1434 50.58 1.97
APC 9x4.5-E 4 14.8 34.99 517.9 13,835 59.0 2066 72.88 3.99
APC 9x6-E 4 14.8 41.07 607.9 13,298 75.6 1904 67.16 3.13
APC 9x7.5-E 4 14.8 59.64 882.7 12,052 85.6 1930 68.08 2.19
APC 10x5-E 4 14.8 48.60 719.3 12,792 60.6 2349 82.86 3.27
 
Prop Prop Li-Po Input Motor Watts Prop Pitch Thrust Thrust Thrust Eff.
Manf. Size Cells Voltage Amps Input RPM Speed Grams Ounces Grams/W
APC 7x4-E 5 18.5 24.11 446.0 18,361 69.5 1515 53.44 3.40
APC 7x5-E 5 18.5 30.97 572.9 17,890 84.7 1513 53.37 2.64
APC 7x6-E 5 18.5 31.84 588.9 17,795 101.1 1604 56.58 2.72
APC 8x4-E 5 18.5 37.35 690.9 17,418 66.0 2025 71.43 2.93
APC 8x6-E 5 18.5 59.39 1098.8 15,909 90.4 2194 77.39 2.00
APC 9x4.5-E 5 18.5 51.93 960.6 16,278 69.4 2972 104.83 3.09
 
Prop Prop Li-Po Input Motor Watts Prop Pitch Thrust Thrust Thrust Eff.
Manf. Size Cells Voltage Amps Input RPM Speed Grams Ounces Grams/W
APC 7x4-E 6 22.2 35.40 785.9 21,302 80.7 2041 71.99 2.60
APC 7x5-E 6 22.2 43.74 970.9 20,650 97.8 2020 71.25 2.08
APC 7x6-E 6 22.2 45.18 1003.0 20,531 116.7 2128 75.06 2.12
APC 8x4-E 6 22.2 52.43 1163.8 19,912 75.4 2656 93.69 2.28
2018 Innov8tive Designs, Inc.
This chart, and the data contained within it, are the property of Innov8tive Designs, Inc., and may not be reproduced without permission from the author.
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
584 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.