Cobra C3515/14 Motor Propeller Data
Motor Wind Motor Kv No-Load Current Motor Resistance I Max P Max (4S)
14-Turn Delta 950 RPM/Volt Io = 1.39 Amps @ 14v Rm = 0.029 Ohms 44 Amps 650 W 
 
Outside Diameter Body Length Total Shaft Length Shaft Diameter Motor Weight
43.0 mm,  1.69 in. 41.0 mm,  1.61 in. 63.0 mm,  2.48 in. 5.00 mm,  0.197 in. 178 gm,   6.28 oz
 
Prop Prop Input Motor Watts Prop Pitch Thrust  Thrust Thrust Eff.
Manf. Size Voltage Amps Input RPM Speed Grams Ounces Grams/W
APC 9x4.7-SF 11.1 13.39 148.6 9,256 41.2 928 32.73 6.25
APC 9x6-SF 11.1 25.10 278.6 8,351 47.4 1192 42.05 4.28
APC 9x7.5-E 11.1 21.38 237.3 8,639 61.4 967 34.11 4.08
APC 9x7.5-SF 11.1 29.03 322.3 8,131 57.7 1161 40.95 3.60
APC 9x9-E 11.1 25.34 281.3 8,377 71.4 956 33.72 3.40
APC 10x3.8-SF 11.1 22.19 246.3 8,546 30.8 1392 49.10 5.65
APC 10x4.7-SF 11.1 23.73 263.3 8,485 37.8 1439 50.76 5.46
APC 10x7-E 11.1 21.92 243.3 8,596 57.0 1291 45.54 5.31
APC 10x7-SF 11.1 33.26 369.2 7,798 51.7 1561 55.06 4.23
APC 10x10-E 11.1 31.29 347.3 7,928 75.1 1129 39.82 3.25
APC 11x3.8-SF 11.1 25.20 279.7 8,394 30.2 1596 56.30 5.71
APC 11x4.7-SF 11.1 29.31 325.3 8,111 36.1 1760 62.08 5.41
APC 11x5.5-E 11.1 23.71 263.2 8,489 44.2 1517 53.51 5.76
APC 11x7-E 11.1 28.03 311.1 8,192 54.3 1601 56.47 5.15
APC 11x7-SF 11.1 40.65 451.2 7,420 49.2 1976 69.70 4.38
APC 11x8-E 11.1 29.97 332.6 8,072 61.2 1555 54.85 4.67
APC 11x8.5-E 11.1 31.91 354.2 7,893 63.5 1560 55.03 4.40
APC 11x10-E 11.1 37.57 417.0 7,589 71.9 1411 49.77 3.38
APC 12x3.8-SF 11.1 37.12 412.0 7,622 27.4 2116 74.64 5.14
APC 12x6-E 11.1 30.42 337.6 8,033 45.6 1860 65.61 5.51
APC 12x6-SF 11.1 47.34 525.5 7,011 39.8 2293 80.88 4.36
APC 12x8-E 11.1 37.81 419.7 7,597 57.6 1684 59.40 4.01
APC 12x10-E 11.1 43.42 482.0 7,266 68.8 1792 63.21 3.72
APC 13x4-E 11.1 24.40 270.8 8,438 32.0 1761 62.12 6.50
APC 13x4.7-SF 11.1 45.94 509.9 7,085 31.5 2465 86.95 4.83
APC 13x6.5-E 11.1 40.49 449.5 7,429 45.7 2237 78.91 4.98
APC 13x8-E 11.1 43.55 483.4 7,241 54.9 2191 77.28 4.53
APC 14x7-E 11.1 48.17 534.6 6,976 46.2 2520 88.89 4.71
APC 15x4-E 11.1 40.43 448.8 7,426 28.1 2599 91.68 5.79
MAS 10x5x3 11.1 18.52 205.6 8,852 41.9 1221 43.07 5.94
MAS 10x7x3 11.1 25.86 287.0 8,321 55.2 1528 53.90 5.32
MAS 11x7x3 11.1 31.17 346.0 8,089 53.6 1804 63.63 5.21
MAS 11x8x3 11.1 34.58 383.8 7,923 60.0 1905 67.20 4.96
MAS 12x6x3 11.1 34.26 380.3 7,956 45.2 2008 70.83 5.28
MAS 12x8x3 11.1 46.57 516.9 7,076 53.6 2358 83.18 4.56
 
Prop Prop Input Motor Watts Prop Pitch Thrust  Thrust Thrust Eff.
Manf. Size Voltage Amps Input RPM Speed Grams Ounces Grams/W
APC 8x6-E 14.8 21.33 315.7 11,690 66.4 1186 41.83 3.76
APC 8x8-E 14.8 28.01 414.5 11,171 84.6 1098 38.73 2.65
APC 9x4.5-E 14.8 19.85 293.8 11,816 50.4 1461 51.53 4.97
APC 9x6-E 14.8 23.00 340.4 11,576 65.8 1446 51.01 4.25
APC 9x7.5-E 14.8 34.91 516.7 10,689 75.9 1506 53.12 2.91
APC 9x9-E 14.8 38.20 565.3 10,390 88.6 1496 52.77 2.65
APC 10x5-E 14.8 27.87 412.4 11,182 52.9 1818 64.13 4.41
APC 10x6-E 14.8 29.86 441.9 11,044 62.8 1943 68.54 4.40
APC 10x7-E 14.8 34.68 513.3 10,698 70.9 2072 73.09 4.04
APC 11x5.5-E 14.8 37.78 559.2 10,424 54.3 2441 86.10 4.37
APC 11x7-E 14.8 44.37 656.6 10,040 66.6 2512 88.61 3.83
APC 12x6-E 14.8 48.48 717.5 9,760 55.5 2918 102.93 4.07
APC 13x4-E 14.8 37.78 559.1 10,469 39.7 2834 99.97 5.07
MAS 8x6x3 14.8 19.86 294.0 11,828 67.2 1315 46.38 4.47
MAS 9x7x3 14.8 30.88 457.0 10,975 72.8 1903 67.13 4.16
MAS 10x5x3 14.8 27.60 408.5 11,154 52.8 1942 68.50 4.75
MAS 10x7x3 14.8 38.98 576.9 10,415 69.0 2374 83.74 4.12
MAS 11x7x3 14.8 46.35 685.9 9,917 65.7 2703 95.34 3.94
 
Prop Prop Input Motor Watts Prop Pitch Thrust  Thrust Thrust Eff.
Manf. Size Voltage Amps Input RPM Speed Grams Ounces Grams/W
APC 7x6-E 18.5 17.69 327.2 15,036 85.4 1154 40.71 3.53
APC 8x4-E 18.5 20.29 375.4 14,796 56.0 1479 52.17 3.94
APC 8x6-E 18.5 32.38 598.9 13,759 78.2 1678 59.19 2.80
APC 8x8-E 18.5 40.63 751.7 13,135 99.5 1527 53.86 2.03
APC 9x4.5-E 18.5 28.79 532.6 14,037 59.8 2134 75.27 4.01
APC 9x6-E 18.5 33.35 616.9 13,676 77.7 2044 72.10 3.31
APC 9x7.5-E 18.5 49.82 921.6 12,459 88.5 2040 71.96 2.21
APC 10x5-E 18.5 41.01 758.7 13,098 62.0 2475 87.30 3.26
APC 10x6-E 18.5 43.06 796.6 12,952 73.6 2659 93.79 3.34
APC 10x7-E 18.5 49.96 924.3 12,453 82.5 2762 97.43 2.99
MAS 8x6x3 18.5 27.84 515.0 14,143 80.4 1912 67.44 3.71
MAS 9x7x3 18.5 42.82 792.1 12,970 86.0 2691 94.92 3.40
MAS 10x5x3 18.5 38.71 716.2 13,288 62.9 2786 98.27 3.89
MAS 10x7x3 18.5 53.96 998.3 12,086 80.1 3242 114.36 3.25
 
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 22.2 18.74 415.9 17,988 68.1 1423 50.19 3.42
APC 7x5-E 22.2 23.58 523.5 17,475 82.7 1440 50.79 2.75
APC 7x6-E 22.2 24.44 542.6 17,335 98.5 1540 54.32 2.84
APC 8x4-E 22.2 28.23 626.6 16,979 64.3 1939 68.40 3.09
APC 8x6-E 22.2 45.58 1011.8 15,590 88.6 2141 75.52 2.12
APC 9x4.5-E 22.2 39.67 880.7 16,041 68.4 2908 102.58 3.30
APC 9x6-E 22.2 46.07 1022.7 15,556 88.4 2642 93.19 2.58
MAS 8x6x3 22.2 36.31 806.1 16,266 92.4 2558 90.23 3.17
MAS 9x7x3 22.2 55.80 1238.8 14,799 98.1 3528 124.45 2.85
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.