Tempest 1708-1270 Performance Test Data
Magnets Motor Wind Motor Kv No-Load Current Motor Resistance I Max P Max (3S)
12-Pole 12-Turn Delta 1270 RPM/Volt Io = 0.37 Amps @ 10v Rm = 0.387 Ohms 8 Amps 90 W
 
Stator Outside Diameter Body Length Total Shaft Length Shaft Diameter Motor Weight
9-Slot 21.0 mm,  0.827 in. 19.5 mm,  0.768 in. 29.5 mm,  1.161 in. 2.00 mm,  0.079 in. 21.2 gm,   0.75 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 0.310 A 0.335 A 0.371 A 0.405 A 1309 RPM/Volt @ 10v 0.3871 Ohms
 
2-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 2 7.4 3.59 26.6 7,351 27.8 210 7.42 7.91
APC 7x4-SF 2 7.4 3.56 26.3 7,366 27.9 204 7.19 7.74
APC 7x5-E 2 7.4 4.33 32.0 6,840 32.4 198 6.99 6.19
APC 7x5-SF 2 7.4 4.12 30.5 6,965 33.0 210 7.39 6.86
APC 7x6-E 2 7.4 4.62 34.2 6,634 37.7 206 7.27 6.03
APC 7x6-SF 2 7.4 4.70 34.8 6,575 37.4 200 7.04 5.75
APC 8x3.8-SF 2 7.4 4.94 36.6 6,410 23.1 272 9.59 7.43
APC 8x4.7-SF 2 7.4 5.41 40.0 6,065 27.0 282 9.94 7.05
APC 8x6-SF 2 7.4 6.35 47.0 5,241 29.8 255 9.00 5.43
APC 9x3.8-SF 2 7.4 5.81 43.0 5,650 20.3 298 10.50 6.93
APC 9x4.7-SF 2 7.4 6.22 46.0 5,321 23.7 304 10.73 6.61
APC 9x6-SF 2 7.4 7.33 54.2 4,360 24.8 280 9.87 5.16
APC 9x7.5-SF 2 7.4 8.27 61.2 4,095 29.1 263 9.29 4.30
APC 10x3.8-SF 2 7.4 7.09 52.5 4,557 16.4 316 11.15 6.02
APC 10x4.7-SF 2 7.4 7.80 57.7 4,421 19.7 334 11.78 5.79
HQ 6x4.5-BN 2 7.4 3.66 27.0 7,323 31.2 186 6.56 6.88
HQ 7x4.5-C 2 7.4 4.15 30.7 6,989 29.8 222 7.83 7.23
 
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 5x4.3-E 3 11.1 3.99 44.2 11,515 46.9 219 7.73 4.95
APC 5x4.5-E 3 11.1 4.05 44.9 11,462 48.8 213 7.53 4.75
APC 5x4.6-E 3 11.1 4.13 45.9 11,400 49.7 229 8.09 5.00
APC 5.25x4.75-E 3 11.1 3.86 42.8 11,600 52.2 194 6.84 4.53
APC 5.25x6.25-E 3 11.1 5.02 55.7 10,705 63.4 173 6.11 3.11
APC 5.5x4.5-E 3 11.1 4.02 44.6 11,469 48.9 204 7.19 4.57
APC 6x4-E 3 11.1 4.39 48.8 11,181 42.4 251 8.85 5.15
APC 6x4.3-E 3 11.1 5.67 63.0 10,222 41.6 322 11.37 5.12
APC 6x4.5-E 3 11.1 5.54 61.5 10,296 43.9 324 11.41 5.26
APC 6x5.5-E 3 11.1 5.57 61.9 10,277 53.5 234 8.26 3.79
APC 6x6-E 3 11.1 5.61 62.2 10,151 57.7 260 9.16 4.17
APC 7x4-E 3 11.1 6.16 68.4 9,682 36.7 371 13.09 5.43
APC 7x4-SF 3 11.1 6.23 69.2 9,652 36.6 364 12.83 5.26
APC 7x5-E 3 11.1 7.08 78.5 8,891 42.1 342 12.06 4.35
APC 7x5-SF 3 11.1 6.91 76.7 9,013 42.7 357 12.61 4.66
APC 7x6-E 3 11.1 7.28 80.8 8,617 49.0 355 12.50 4.39
APC 7x6-SF 3 11.1 7.68 85.2 8,310 47.2 326 11.51 3.83
APC 8x3.8-SF 3 11.1 7.94 88.2 7,963 28.7 436 15.39 4.95
APC 8x4.7-SF 3 11.1 8.85 98.3 7,825 34.8 469 16.53 4.77
HQ 6x4.5-BN 3 11.1 6.12 67.9 9,825 41.9 326 11.50 4.80
HQ 6x4.5-C 3 11.1 4.77 52.9 10,905 46.5 303 10.67 5.72
HQ 7x4.5-C 3 11.1 6.87 76.3 9,172 39.1 384 13.53 5.03
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.