Cobra 2826-EF1 Performance Test Data
Magnets Motor Wind Motor Kv No-Load Current Motor Resistance I Max P Max (6S)
14-Pole 7-Turn Delta 1200 RPM/Volt Io = 2.20Amps @ 10v Rm = 0.018 Ohms 70 Amps 1555 W
 
Stator Outside Diameter Body Length Total Shaft Length Shaft Diameter Motor Weight
12-Slot 35.0 mm, 1.378 in. 45.9 mm, 1.807 in. 56.0 mm, 2.205 in. 5.00 mm, 0.197 in. 176 gm, 6.21 oz
 
Test Data From Input 8.0 V 10.0 V 12.0V 14.0V Measured Kv value Measured Rm Value
Sample Motor Io Value 2.019 A 2.204 A 2.368 A 2.554 A 1197 RPM/Volt @ 10V 0.0177 Ohms
 
3-cell Li-Po Test Data
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 9x6-E 3 11.1 29.09 322.9 11,300 64.2 1353 47.73 4.19
APC 9x7.5-E 3 11.1 44.48 493.7 10,566 75.0 1463 51.61 2.96
APC 9x9-E 3 11.1 50.67 562.5 10,372 88.4 1437 50.69 2.55
APC 10x5-E 3 11.1 35.56 394.8 11,149 52.8 1760 62.08 4.46
APC 10x6-E 3 11.1 40.20 446.2 10,915 62.0 1833 64.66 4.11
APC 10x7-E 3 11.1 46.13 512.1 10,579 70.1 1878 66.24 3.67
APC 10x8-E 3 11.1 51.63 573.0 10,348 78.4 1858 65.54 3.24
APC 10x10-E 3 11.1 65.56 727.7 9,680 91.7 1609 56.76 2.21
APC 11x5.5-E 3 11.1 49.73 552.0 10,373 54.0 2346 82.75 4.25
APC 11x7-E 3 11.1 58.73 651.9 10,027 66.5 2456 86.63 3.77
APC 11x8-E 3 11.1 63.13 700.7 9,760 73.9 2241 79.05 3.20
APC 11x8.5-E 3 11.1 67.59 750.2 9,622 77.4 2338 82.47 3.12
APC 11x10-E 3 11.1 75.71 840.4 9,256 87.7 2060 72.66 2.45
APC 12x6-E 3 11.1 64.13 711.9 9,755 55.4 2845 100.35 4.00
APC 12x8-E 3 11.1 76.16 845.4 9,185 69.6 2450 86.42 2.90
APC 13x4-E 3 11.1 55.28 613.6 10,080 38.2 2829 99.79 4.61
APC 13x5.5-E 3 11.1 68.03 755.1 9,569 49.8 3144 110.90 4.16
MAS 8x6x3 3 11.1 26.94 299.0 11,789 67.0 1271 44.83 4.25
MAS 9x7x3 3 11.1 42.10 467.3 11,052 73.3 1889 66.63 4.04
MAS 10x5x3 3 11.1 38.29 425.0 11,244 53.2 1937 68.32 4.56
MAS 10x7x3 3 11.1 53.70 596.1 10,477 69.4 2359 83.21 3.96
MAS 11x7x3 3 11.1 63.90 709.3 10,024 66.4 2725 96.12 3.84
MAS 11x8x3 3 11.1 68.66 762.2 9,796 74.2 2773 97.81 3.64
MAS 12x6x3 3 11.1 70.71 784.8 9,709 55.2 3065 108.11 3.91
                     
4-cell Li-Po Test Data
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 8x4-E 4 14.8 29.72 439.9 15,546 58.9 1576 55.59 3.58
APC 8x6-E 4 14.8 43.26 640.3 14,764 83.9 1856 65.47 2.90
APC 8x8-E 4 14.8 52.48 776.7 14,280 108.2 1779 62.75 2.29
APC 9x4.5-E 4 14.8 43.58 645.0 14,785 63.0 2353 83.00 3.65
APC 9x6-E 4 14.8 50.36 745.3 14,312 81.3 2228 78.59 2.99
APC 9x7.5-E 4 14.8 75.09 1111.4 13,120 93.2 2275 80.25 2.05
APC 10x5-E 4 14.8 60.35 893.1 13,875 65.7 2704 95.38 3.03
APC 10x6-E 4 14.8 67.09 992.9 13,620 77.4 2783 98.17 2.80
APC 10x7-E 4 14.8 76.51 1132.3 13,039 86.4 2842 100.25 2.51
MAS 8x6x3 4 14.8 42.72 632.2 15,096 85.8 2165 76.37 3.42
MAS 9x7x3 4 14.8 65.40 968.0 13,880 92.0 3031 106.91 3.13
MAS 10x5x3 4 14.8 60.48 895.2 14,157 67.0 3187 112.42 3.56
MAS 10x7x3 4 14.8 83.90 1241.7 12,879 85.4 3733 131.68 3.01
 
5-cell Li-Po Test Data
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 7x4-E 5 18.5 32.35 598.5 19,744 74.8 1737 61.27 2.90
APC 7x5-E 5 18.5 38.08 704.5 19,019 90.1 1707 60.21 2.42
APC 7x6-E 5 18.5 39.78 735.9 18,909 107.4 1813 63.95 2.46
APC 7x7-E 5 18.5 48.31 893.8 18,465 122.4 1785 62.96 2.00
APC 8x4-E 5 18.5 46.42 858.8 18,570 70.3 2274 80.21 2.65
APC 8x6-E 5 18.5 65.94 1219.9 17,497 99.4 2619 92.38 2.15
APC 8x8-E 5 18.5 78.65 1455.0 16,809 127.3 2484 87.62 1.71
APC 9x4.5-E 5 18.5 66.35 1227.4 17,429 74.3 3344 117.95 2.72
APC 9x6-E 5 18.5 76.72 1419.2 16,916 96.1 3132 110.48 2.21
MAS 7x4x3 5 18.5 30.67 567.3 19,898 75.4 1694 59.75 2.99
MAS 8x6x3 5 18.5 60.88 1126.4 18,033 102.5 3113 109.81 2.76
 
6-cell Li-Po Test Data
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 6x6-E 6 22.2 35.46 787.2 24,169 137.3 1442 50.86 1.83
APC 6.5x5.0-P 6 22.2 32.81 728.5 24,375 115.4 1533 54.07 2.10
APC 6.5x5.5-P 6 22.2 35.30 783.7 24,200 126.0 1565 55.20 2.00
APC 6.5x6.0-P 6 22.2 39.13 868.8 23,927 135.9 1572 55.45 1.81
APC 6.5x6.5-P 6 22.2 41.19 914.5 23,791 112.6 1559 54.99 1.70
APC 7x4-E 6 22.2 49.91 1108.0 23,183 87.8 2436 85.93 2.20
APC 7x5-E 6 22.2 57.79 1282.9 22,262 105.4 2395 84.48 1.87
APC 7x6-E 6 22.2 56.89 1262.9 21,894 124.4 2444 86.21 1.94
APC 7x7-E 6 22.2 67.06 1488.8 21,294 141.2 2365 83.42 1.59
MAS 7x4x3 6 22.2 44.24 982.1 23,577 89.3 2288 80.71 2.33
MAS 8x6x3 6 22.2 82.20 1824.7 20,662 117.4 3838 135.38 2.10
2019 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.