Thurst times pitch speed		Thrust plus pitch speed

The original GWS HD prop calculations were inaccurate because of faulty prop data entry into Drive Calclator. I have now tested and redone the numbers for the GWS HD 10x8 prop. Others will be tested soon and corrected. The GWS HD prop data, other than for the HD 10x8, is to be considered suspect until this text is updated.      Only actually flying the plane with various props will demonstrate which one gives the best all around performance. This theory does suggest which props the modeler might wish to try first.      I have used various 10-inch diameter props with my 3S "A123" 2300mAh powered planes. Over the last two years (all with different motors) I've only used the Master Airscrew 10x8 G/F 3 Series props. I currently have that prop on my Son of Swallow, Fusion 380 and my parkzone T-28 Trojan. This data was not available to me at the time of selecting the prop, but now I can see why I like this prop so much for this application.      IMPORTANT NOTICE! - Please read and heed --- The following are possible recommendations only. It is up to the modeler to determine whether any of these suggestions may actually work. A power meter/watt meter/Whattmeter is an ESSENTIAL TOOL when modifying any power system. Do NOT attempt any modification to any power system without a power meter to verify the actual amp draw!!! Be absolutely sure that your ESC with 4 servos and the motor can handle the amp draw shown on the power meter. The Motors, Electronic Speed Controls (ESCs), and Props Turnigy SK35-30 1100, weight: 90g Kv: 1100 max amps on 3S: 31.8 (max I would use 31.8 amps * 0.80 = 25 amps) - Price $16.95 Notes: The ESC should be rated for at least 31.3 amps based on a maximum 25 amp draw. A 36 amp rated ESC like the Castle Creations Thunderbird 36 ($33.99) might be a good choice. Prop Amps Watts In RPM Thrust oz. Pitch Speed MPH thrust + pitch speed MA std. wood 10x7 24 220 7750 36 51 87 parkzone 9.5x7.5 22 200 7970 31 57 88 APC sport 11x6 25 225 7690 44 44 88 Aeronaut E 10.5x7 22 204 7930 36 53 89 MA G/F 3 Series 10x8 23 208 7890 32 60 92 APC sport 10x8 24 218 7770 33 59 92 Aeronaut E 10.5x8 24 218 7780 35 59 94 Scorpion SII-3008-1220, weight: 95g Kv: 1220 max amps on 3S: 33.6 (max I would use 33.6 amps * 0.80 = 27 amps) - Price $56.69 Notes: The ESC should be rated for at least 36 amps. A 36 amp rated ESC like the Castle Creations Thunderbird 36 ($33.99) might be a good choice. Prop Amps Watts In RPM Thrust oz. Pitch Speed MPH thrust + pitch speed Aeronaut E 10x6 24 215 8680 35 49 84 APC sport 10x6 25 229 8400 36 48 84 Aeronaut E 10.5x6 27 245 8070 39 46 85 Aeronaut E 9.5x7 24 219 8600 31 57 88 APC sport 10x7 27 245 8080 34 54 88 GWS HD 10x6 23 207 8830 39 50 89 APC sport 9x8 25 226 8450 27 64 91 APC E 9x7.5 25 229 8400 31 60 91 APC E 10x7 27 242 8140 38 54 92 Aeronaut E 10x7 27 240 8190 39 54 93 Turnigy 3632, weight: 99g Kv: 1200 max amps on 3S: 35 (max I would use 35 amps * 0.80 = 28 amps) - Price $17.84 Notes: The ESC should be rated for at least 36 amps. A 36 amp rated ESC like the Castle Creations Thunderbird 36 ($33.99) might be a good choice. Prop Amps Watts In RPM Thrust oz. Pitch Speed MPH thrust + pitch speed APC sport 10x6 23 206 8320 35 47 82 Aeronaut E 10.5x6 25 223 8060 39 46 85 APC sport 10x7 25 223 8070 34 53 87 MA std. wood 10x7 27 245 7740 36 51 87 parkzone 9.5x7.5 25 226 8010 31 57 88 APC sport 11x6 28 250 7660 44 44 88 Aeronaut E 10.5x7 26 229 7960 37 53 90 APC E 10x7 24 219 8120 37 54 91 Aeronaut E 10x7 24 217 8150 38 54 92 APC sport 10x8 27 244 7760 33 59 92 MA G/F 3 Series 10x8 26 233 7900 33 60 93 Aeronaut E 10.5x8 27 243 7770 35 59 94 GWS HD 11x7 ?? ??? ???? ?? ?? ?? Suppo 2814-08 aka BP A2814-8, weight: 103g Kv: 1100 max amps on 3S: 36.4 (max I would use 36.4 amps * 0.80 = 29 amps) Price: $26.95/$29.95 Notes: The ESC should be rated for at least 36 amps. A 36 amp rated ESC like the Castle Creations Thunderbird 36 ($33.99) might be a good choice. Prop Amps Watts In RPM Thrust oz. Pitch Speed MPH thrust + pitch speed MA std. wood 10x7 22 203 7300 32 48 80 APC sport 11x6 23 209 7250 40 41 81 MA std. wood 11x7 26 235 6810 38 45 83 APC sport 11x7 26 238 6770 38 45 83 Aeronaut E 10x8 23 212 7160 30 54 84 APC sport 10x8 22 201 7320 30 55 85 GWS HD 10x8 24 214 7120 31 54 85 MA std. wood 10x8 24 218 7080 31 54 85 APC E 11x7 24 218 7070 39 47 86 Aeronaut E 10.5x8 22 201 7330 31 56 87 MA std. wood 11x8 28 250 6570 37 50 87 APC sport 11x8 27 243 6680 36 51 87 APC sport 12x7 29 256 6540 44 43 87 APC E 11x8 27 240 6730 37 51 88 APC sport 10x9 25 223 7000 29 60 89 GWS HD 11x7 ?? ??? ???? ?? ?? ?? APC E 11x8.5 26 232 6850 37 55 92 APC E 12x8 29 256 6490 46 49 95 GWS HD 12x8 ?? ??? ???? ?? ?? ?? Hacker A30 16M, weight: 104.5g Kv: 1060 max amps on 3S: 36.9 (max I would use 36.9 amps * 0.80 = 29 amps) - Price $59.99 Notes: The ESC should be rated for at least 35 amps. A 36 amp rated ESC like the Castle Creations Thunderbird 36 ($33.99) might be a good choice. Prop Amps Watts In RPM Thrust oz. Pitch Speed MPH thrust + pitch speed GWS HD 11x7 ?? ??? ???? ?? ?? ?? parkzone 9.5x7.5 22 201 7920 30 56 86 MA std. wood 10x7 24 221 7700 35 51 86 APC sport 11x6 25 226 7640 44 43 87 Aeronaut E 10.5x7 23 205 7880 36 52 88 APC E 11x8.5 29 260 7260 42 58 90 MA G/F 3 Series 10x8 23 208 7840 32 59 91 APC sport 10x8 24 219 7720 33 58 91 Aeronaut E 10x8 26 232 7580 34 57 91 MA std. wood 11x7 29 261 7260 43 48 91 GWS HD 10x8 27 239 7500 35 57 92 MA std. wood 10x8 27 239 7500 35 57 92 Aeronaut E 10.5x8 24 219 7720 35 58 93 APC E 11x7 27 240 7490 44 50 94 APC E 10x9 27 246 7430 33 63 96 AXI 2814/16, weight: 106g Kv: 1035 max amps on 3S: 37.5 (max I would use 37.5 amps * 0.80 = 30 amps) - Price $94.99 Notes: The ESC should be rated for at least 35/36 amps. A 36 amp rated ESC like the Castle Creations Thunderbird 36 ($33.99) might be a good choice. Prop Amps Watts In RPM Thrust oz. Pitch Speed MPH thrust + pitch speed Aeronaut E 10.5x6 23 208 8030 39 46 85 APC sport 10x7 23 208 8040 34 53 87 MA std. wood 10x7 26 231 7750 36 51 87 parkzone 9.5x7.5 23 211 8000 31 57 88 APC sport 11x6 27 236 7690 44 44 88 Aeronaut E 10.5x7 24 215 7950 37 53 90 APC E 10x7 22 204 8080 37 54 91 Aeronaut E 10x7 22 202 8120 38 54 92 MA G/F 3 Series 10x8 24 218 7910 32 60 92 APC sport 10x8 25 230 7770 33 59 92 Aeronaut E 10x8 27 242 7620 34 58 92 MA std. wood 10x8 28 249 7530 35 57 92 GWS HD 10x8 28 249 7530 35 57 92 Aeronaut E 10.5x8 25 229 7780 35 59 94 APC E 11x7 28 250 7520 44 50 94 APC sport 10x9 29 256 7460 33 64 97 GWS HD 11x7 ?? ??? ???? ?? ?? ?? Turnigy TR 35-36C, weight: 106g Kv: 1100 max amps: 37.5 (max I would use 37.5 amps * 0.80 = 30 amps) - Price $25.20 Notes: The ESC should be rated for at least 35/36 amps. A 36 amp rated ESC like the Castle Creations Thunderbird 36 ($33.99) might be a good choice. Prop Amps Watts In RPM Thrust oz. Pitch Speed MPH thrust + pitch speed Aeronaut E 10.5x6 24 213 7860 37 45 82 APC sport 10x7 23 213 7870 32 52 84 MA std. wood 10x7 26 233 7530 34 50 84 APC sport 11x6 26 237 7450 42 42 84 parkzone 9.5x7.5 24 216 7820 30 56 86 Aeronaut E 10.5x7 24 219 7760 35 51 86 MA std. wood 11x7 30 266 6950 40 46 86 APC sport 11x7 30 269 6900 40 46 86 MA std. wood 10x8 28 248 7260 32 55 87 APC E 10x7 23 210 7930 35 53 88 APC sport 10x8 26 232 7550 31 57 88 Aeronaut E 10x8 27 242 7360 32 56 88 GWS HD 10x8 28 246 7290 33 55 88 Aeronaut E 10x7 23 208 7960 36 53 89 MA G/F 3 Series 10x8 25 222 7710 31 58 89 APC E 11x7 28 249 7250 41 48 89 Aeronaut E 10.5x8 26 231 7560 33 57 90 APC sport 10x9 28 253 7170 31 61 92 APC E 11x8.5 30 264 6990 38 56 94 GWS HD 11x7 ?? ??? ???? ?? ?? ?? Scorpion SII-3014-1220, weight: 129g Kv: 1220 max amps on 3S: 46 (max I would use 46 amps * 0.80 = 36.8 amps) - Price $61.41 Notes: The ESC should be rated for at least 45 amps. A 54 amp rated ESC like the Castle Creations Thunderbird 54 would be a good idea. ($40.99). Prop Amps Watts In RPM Thrust oz. Pitch Speed MPH thrust + pitch speed Aeronaut E 9x5 25 228 9710 38 46 84 Aeronaut E 9.5x5 23 207 9960 38 47 85 Aeronaut 9.5x6 24 220 9750 39 55 94 APC E 9x6 24 216 9800 39 56 95 APC sport 10x6 30 265 9210 43 52 95 Aeronaut E 10x6 28 250 9460 42 54 96 GWS HD 10x6 27 238 9540 45 54 99 Aeronaut 9.5x7 28 252 9370 37 62 99 Aeronaut E 10.5x6 33 288 8930 48 51 99 APC sport 10x7 33 287 8940 42 59 101 MA std. wood 10x7 37 316 8590 44 57 101 APC E 9x7.5 31 270 9150 37 65 102 parkzone 9.5x7.5 34 295 8850 39 63 102 APC sport 9x8 29 261 9250 33 70 103 Aeronaut E 10.5x7 34 296 8830 45 59 104 APC sport 11x6 38 327 8540 55 49 104 APC E 10x7 32 284 8980 46 60 106 MA G/F 3 Series 10x8 35 300 8780 40 67 107 Aeronaut E 10x7 32 280 9040 47 60 107 APC sport 10x8 36 314 8620 41 65 107 Aeronaut E 10.5x8 36 313 8620 43 65 108 GWS HD 11x7 ?? ??? ???? ?? ?? ??? Scorpion SII-3014-1040, weight: 129g Kv: 1040 max amps on 3S: 46 (max I would use 46 amps * 0.80 = 36.8 amps) - Price $61.41 Notes: The ESC should be rated for at least 40 amps. A 54 amp rated ESC like the Castle Creations Thunderbird 54 would be a good idea. ($40.99). Prop Amps Watts In RPM Thrust oz. Pitch Speed MPH thrust + pitch speed APC sport 10x6 22 200 8440 36 48 84 Aeronaut E 10.5x6 24 217 8210 40 47 87 APC sport 10x7 24 216 8220 35 54 89 parkzone 9.5x7.5 24 221 8170 32 58 90 MA std. wood 10x7 27 241 7940 38 53 91 APC sport 11x6 28 247 7870 46 45 91 Aeronaut E 10.5x7 25 224 8130 38 54 92 APC E 10x7 23 213 8250 39 55 94 Aeronaut E 10x7 23 210 8290 40 55 95 MA G/F 3 Series 10x8 25 228 8090 34 61 95 APC sport 10x8 27 240 7960 35 60 95 Aeronaut E 10x8 28 253 7800 36 59 95 GWS HD 10x8 30 262 7700 37 58 95 MA std. wood 10x8 29 261 7720 37 58 95 MA std. wood 11x7 32 284 7460 46 49 95 APC sport 11x7 33 288 7420 46 49 95 Aeronaut E 10.5x8 27 239 7960 37 60 97 APC E 11x7 30 262 7710 47 51 98 APC sport 10x9 30 268 7640 35 65 100 APC E 11x8 34 294 7350 44 56 100 APC sport 11x8 34 296 7330 44 56 100 MA std. wood 11x8 35 307 7200 45 55 100 APC sport 12x7 36 309 7180 53 48 101 GWS HD 11x7 ?? ??? ???? ?? ?? ??? APC E 11x8.5 32 285 7450 44 60 104 GWS HD 12x8 ?? ??? ???? ?? ?? ??? Turnigy TR 35-42C, weight: 132g Kv: 1100 max amps: 46.7 (max I would use 46.7 amps * 0.80 = 37.3 amps) - Price $21.00 Notes: The ESC should be rated for at least 45 amps. A 54 amp rated ESC like the Castle Creations Thunderbird 54 would be a good idea. ($40.99). Prop Amps Watts In RPM Thrust oz. Pitch Speed MPH thrust + pitch speed APC sport 9x8 23 212 8490 27 64 81 Aeronaut E 10x6 22 200 8650 35 49 84 APC sport 10x6 24 215 8450 36 48 84 Aeronaut E 10.5x6 26 234 8200 40 47 87 Aeronaut E 9.5x7 22 204 8600 31 57 88 APC sport 10x7 26 233 8200 35 54 89 MA std. wood 10x7 29 256 7880 37 52 89 parkzone 9.5x7.5 26 237 8150 32 58 90 APC sport 11x6 29 260 7810 46 44 90 APC E 9x7.5 24 216 8440 31 60 91 Aeronaut E 10.5x7 27 240 8100 38 54 92 MA std. wood 11x7 34 294 7330 44 49 93 APC sport 11x7 34 298 7280 45 48 93 Aeronaut E 10x7 25 227 8290 39 55 94 APC E 10x7 26 230 8250 39 55 94 APC sport 10x8 29 254 7900 34 60 94 Aeronaut E 10x8 30 267 7730 35 59 94 GWS HD 10x8 31 274 7620 36 58 94 MA std. wood 10x8 31 274 7630 36 58 94 MA G/F 3 Series 10x8 27 244 8060 34 61 95 Aeronaut E 10x7 25 230 8300 40 55 95 APC sport 11x8 35 305 7180 42 54 96 MA std. wood 11x8 36 314 7040 43 53 96 Aeronaut E 10.5x8 29 254 7910 37 60 97 APC E 11x7 31 275 7620 46 51 97 APC E 11x8 35 302 7220 42 55 97 APC sport 10x9 32 280 7540 34 64 98 APC sport 12x7 37 316 7020 51 47 98 APC E 11x8.5 34 294 7340 43 59 102 GWS HD 11x7 ?? ??? ???? ?? ?? ??? APC E 12x8 37 321 6940 53 53 106 GWS HD 12x8 ?? ??? ???? ?? ?? ??? TowerPro 3015-7, weight: 134g Kv: 1000 max amps on 3S: 47.4 (max I would use 47.4 amps * 0.80 = 37.9 amps) Price: $15.95 Notes: The ESC should be rated for at least 45 amps. A 54 amp rated ESC like the Castle Creations Thunderbird 54 would be a good idea. ($40.99). I measured the Kv of mine at 1065 not the advertised 1000 Prop Amps Watts In RPM Thrust oz. Pitch Speed MPH thrust + pitch speed Aeronaut E 10.5x6 23 207 7890 38 45 83 MA std. wood 10x7 25 228 7600 34 50 84 APC sport 10x7 23 206 7900 33 52 85 parkzone 9.5x7.5 23 209 7860 30 56 86 APC sport 11x6 26 233 7540 43 43 86 Aeronaut E 10.5x7 23 213 7800 35 52 87 APC E 10x7 22 202 7950 36 53 89 MA std. wood 11x7 30 265 7120 42 47 89 APC sport 11x7 30 269 7070 42 47 89 Aeronaut E 10x7 22 200 7970 37 53 90 MA G/F 3 Series 10x8 24 216 7760 31 59 90 APC sport 10x8 25 227 7630 32 58 90 Aeronaut E 10x8 27 239 7470 33 57 90 GWS HD 10x8 27 244 7400 34 56 90 MA std. wood 10x8 27 245 7380 34 56 90 APC E 11x7 28 246 7370 42 49 91 Aeronaut E 10.5x8 25 226 7630 34 58 92 MA std. wood 11x8 32 285 6860 40 52 92 APC E 11x10 31 272 7030 40 53 93 APC sport 11x8 31 276 6990 40 53 93 APC sport 12x7 33 287 6830 48 45 93 APC sport 10x9 28 251 7300 32 62 94 APC sport 12x8 37 321 6390 47 48 95 APC E 11x8.5 30 264 7140 40 57 97 GWS HD 11x7 ?? ??? ???? ?? ?? ?? APC pattern 12x9 36 308 6560 44 56 100 APC E 12x8 33 291 6780 51 51 102 GWS HD 12x8 ?? ??? ???? ?? ?? ??? APC sport 13x8 36 315 6470 55 49 104 Hacker A30 10L, weight: 144.6g Kv: 1185 max amps: 50 Price: $67.99 Notes: The ESC should be rated for at least 50 amps. A 54 amp rated ESC like the Castle Creations Thunderbird 54 would be a good idea. ($40.99). Prop Amps Watts In RPM Thrust oz. Pitch Speed MPH thrust+ pitch speed APC sport 10x6 25 222 8650 38 49 87 Aeronaut E 9.5x7 23 211 8780 32 58 90 Aeronaut E 10.5x6 27 243 8410 43 48 91 APC E 9x7.5 25 224 8630 32 61 93 APC sport 10x7 27 242 8430 37 56 93 parkzone 9.5x7.5 28 248 8370 34 59 93 MA std. wood 10x7 30 269 8130 40 54 94 APC sport 9x8 24 219 8680 29 66 95 Aeronaut E 10.5x7 28 251 8330 40 55 95 APC sport 11x6 31 275 8060 49 46 95 APC E 10x7 27 239 8460 41 56 97 Aeronaut E 10x7 26 236 8500 42 56 98 GWS HD 10x8 33 292 7870 39 59 98 MA G/F 3 Series 10x8 29 254 8290 36 63 99 APC sport 10x8 30 267 8150 37 62 99 Aeronaut E 10x8 32 281 7990 38 61 99 MA std. wood 10x8 33 289 7900 39 60 99 MA std. wood 11x7 36 313 7630 48 51 99 APC sport 11x7 37 317 7590 49 50 99 Aeronaut E 10.5x8 30 266 8160 39 62 101 APC E 11x7 33 290 7890 49 52 101 APC E 11x8 38 324 7510 46 57 103 APC sport 10x9 34 296 7820 37 67 104 APC E 11x8.5 37 315 7610 46 61 107 GWS HD 11x7 30 269 8130 54 54 108 AXI 2820/10, weight: 151g Kv: 1200 max amps: 42 Price $99.99 Notes: The ESC should be rated for at least 42 amps. A 54 amp rated ESC like the Castle Creations Thunderbird 54 would be a good idea. ($40.99). Prop Amps Watts In RPM Thrust oz. Pitch Speed MPH thrust + pitch speed GWS HD 10x6 24 218 9260 33 53 86 Aeronaut E 9.5x6 22 201 9439 37 54 91 APC sport 11x6 34 301 8380 43 48 91 APC sport 10x6 27 244 8990 41 51 92 Aeronaut E 9.5x7 26 231 9120 35 60 95 Aeronaut E 10.5x6 30 267 8750 46 50 96 APC sport 10x7 30 266 8760 40 58 98 APC sport 9x8 27 241 9020 31 68 99 APC E 9x7.5 28 248 8950 35 64 99 parkzone 9.5x7.5 31 273 8680 37 62 99 MA std. wood 10x7 34 295 8450 43 56 99 Aeronaut E 10.5x7 31 275 8660 44 57 101 APC E 10x7 30 263 8790 44 58 102 MA G/F 3 Series 10x8 31 276 8590 38 65 103 Aeronaut E 10x7 29 259 8830 45 59 104 APC sport 10x8 33 293 8470 40 64 104 Aeronaut E 10x8 35 308 8300 41 63 104 GWS HD 10x8 37 318 8120 42 62 104 MA std. wood 10x8 36 317 8210 42 62 104 Aeronaut E 10.5x8 33 299 8480 42 64 108 APC E 11x7 37 318 8200 54 54 108 GWS HD 11x7 34 295 8450 58 56 114 KD A36-12L, weight: 152g Kv: 1000 max amps: 37 Price: $29.95 Notes: The ESC should be rated for at least 37 amps. A 54 amp rated ESC like the Castle Creations Thunderbird 54 would be a good idea. ($40.99). Prop Amps Watts In RPM Thrust oz. Pitch Speed MPH thrust + pitch speed APC sport 9x8 22 205 8420 27 64 81 APC sport 10x6 23 207 8380 36 48 84 APC E 9x7.5 23 208 8380 30 56 86 Aeronaut E 10.5x6 25 226 8140 40 46 86 APC sport 10x7 25 225 8150 35 54 89 MA std. wood 10x7 28 249 7840 37 52 89 APC sport 11x6 28 254 7780 45 44 89 parkzone 9.5x7.5 25 229 8100 32 58 90 Aeronaut E 10.5x7 26 233 8050 38 53 91 APC E 10x7 24 222 8200 38 54 92 Aeronaut E 10x8 29 260 7700 35 58 93 GWS HD 10x8 30 264 7580 36 57 93 MA std. wood 11x7 33 288 7320 44 49 93 APC sport 11x7 33 292 7280 45 48 93 Aeronaut E 10x7 24 219 8230 39 55 94 MA G/F 3 Series 10x8 27 240 7960 34 60 94 APC sport 10x8 28 247 7870 34 60 94 APC E 11x7 30 268 7600 45 50 95 Aeronaut E 10.5x8 27 247 7870 36 60 96 APC sport 11x8 34 299 7180 42 54 96 APC E 11x8 34 296 7210 42 55 97 MA std. wood 10x8 30 267 7600 36 58 98 APC sport 10x9 31 273 7520 34 64 98 APC sport 12x7 36 311 7020 51 47 98 MA std. wood 11x8 37 317 7660 49 51 100 GWS HD 11x7 28 249 7850 50 52 102 APC E 11x8.5 33 288 7320 43 59 102 APC E 12x8 36 316 6950 54 53 107 GWS HD 12x8 35 307 7070 59 54 113 Turnigy TR 35-48-A, weight: 163g Kv: 1100 max amps: 47 Price: $23.80 Notes: The ESC should be rated for at least 47 amps. A 54 amp rated ESC like the Castle Creations Thunderbird 54 would be a good idea. ($40.99). Prop Amps Watts In RPM Thrust oz. Pitch Speed MPH thrust + pitch speed Aeronaut E 10x6 23 210 8810 36 50 86 APC sport 10x6 25 226 8640 38 49 87 GWS HD 10x6 22 201 8900 39 51 90 Aeronaut E 9.5x7 24 214 8760 32 58 91 Aeronaut E 10.5x6 27 247 8420 43 48 91 APC E 9x7.5 25 228 8620 32 61 93 APC sport 10x7 27 246 8430 37 56 93 parkzone 9.5x7.5 28 251 8370 34 59 93 APC sport 9x8 25 223 8670 29 66 95 Aeronaut E 10.5x7 28 254 8340 40 55 95 APC sport 11x6 31 278 8080 49 46 95 MA std. wood 10x7 31 272 8140 42 54 96 APC E 10x7 27 243 8460 41 56 97 Aeronaut E 10x7 27 239 8500 42 56 98 MA G/F 3 Series 10x8 30 262 8250 36 63 99 APC sport 10x8 30 270 8160 37 62 99 Aeronaut E 10x8 32 284 8000 38 61 99 GWS HD 10x8 33 291 7860 39 60 99 MA std. wood 10x8 33 292 7920 39 60 99 MA std. wood 11x7 37 316 7650 48 51 99 APC sport 11x7 37 320 7610 49 50 99 Aeronaut E 10.5x8 30 270 8170 39 62 101 APC E 11x7 33 293 7910 50 52 102 APC sport 10x9 34 299 7840 37 67 104 GWS HD 11x7 31 272 8140 54 54 108 APC E 11x8.5 37 318 7630 47 61 108 Scorpion SII-3020-1110, weight: 166g Kv: 1110 max amps: 60 Notes: The ESC should be rated for at least 50 amps. A 54 amp rated ESC like the Castle Creations Thunderbird 54 would be a good idea. ($40.99). Prop Amps Watts In RPM Thrust oz. Pitch Speed MPH thrust + pitch speed APC sport 9x8 27 241 9100 32 69 91 APC sport 10x6 27 244 9060 42 51 93 GWS HD 10x6 24 217 9340 43 53 96 Aeronaut E 9.5x7 25 231 9200 35 61 96 Aeronaut E 10.5x6 30 267 8830 47 50 97 APC E 9x7.5 28 249 9020 36 64 100 APC sport 10x7 30 266 8840 41 59 100 parkzone 9.5x7.5 31 273 8760 38 62 100 MA std. wood 10x7 34 296 8530 44 57 101 Aeronaut E 10.5x7 31 276 8740 44 58 102 APC sport 11x6 35 306 8480 54 48 102 APC E 10x7 30 263 8870 45 59 104 GWS HD 10x8 38 323 8200 42 62 104 Aeronaut E 10x7 29 259 8910 46 59 105 Aeronaut E 10x8 36 310 8380 42 63 105 MA std. wood 10x8 37 317 8270 42 63 105 MA G/F 3 Series 10x8 33 288 8660 40 66 106 APC sport 10x8 34 297 8570 41 65 106 MA std. wood 10x8 37 322 8300 43 63 106 Aeronaut E 10.5x8 33 293 8560 43 65 108 APC E 11x7 37 323 8290 55 55 110 GWS HD 11x7 34 295 8510 59 56 115 Pitch Speed to Stall Speed Ratio Wing Loading Formula Weight in ounces (oz.) divided by (/) the wing area in square feet (sq.ft.) One sq.ft. is 144 sq.in. Wing area in sq.in. / 144 = wing area in sq.ft. Stall Speed Formula square root (SQRT) of the wing loading (square feet divided by (/) the weight in ounces (oz.)) times (*) 3.7 Pitch Speed Formula Pitch times revolutions per minute (RPM) divided by 1056 Pitch Speed to Stall Speed Ratio Formula Pitch Speed divided by (/) Stall Speed Example 1: parkzone T-28 with stock motor, 9.5x7.5 prop and 3S 1800mAh Li-Poly Battery Ready to Fly (RTF) weight: 30.62 oz. Wing area: 315 sq.in. (315 sq.in. / 144 sq.in. (1 sq.ft.) = 2.1875 sq.ft.) Prop: parkzone 9.5x7.5 (pitch 7.5 inches) Measured RPM: 7,740 Wing loading: 30.62 oz. / 2.1875 sq.ft. = 13.997714 oz./sq.ft Pitch Speed: (7.5 * 7740) / 1056 = 58050 / 1056 = 54.971591 mph Note: The Pitch Speed is NOT the speed that the aircraft attains in level flight at wide-open throttle (WOT). The flying speed in level flight will almost always be less than the Pitch Speed. The flying speed, known as Vopt (velocity optimum) in Drive Calculator, is usually 60% to 80% of the pitch speed. Stall Speed: SQRT(13.997714) * 3.7 = 3.7413519 * 3.7 = 13.843002 mph Note: there is no reason to use all of the decimal point digits as the numbers are only approximations. Pitch Speed to Stall Speed Ratio: 55 mph / 13.8 mph = 3.9855072 or about 4:1      Drive Calculator makes a velocity optimum (Vopt) prediction that suggests 45.26 mph. Using that number divided by the stall speed still gives a ratio of 3.28:1      The pitch speed to stall speed ratio can be used to compare various power systems and props, but be aware that the Vopt will be a closer prediction of actual expected flight speed in level flight. What does this ratio mean as it relates to expected performance?      According to Keith Shaw's article Electric Sport Scale published in Model Builder in July of 1987, "In order to just do a nice inside loop, the plane must enter at twice the stall speed. To do clean inside loops, rolls, and other sport-type aerobatics, three times stall speed is needed. Anything over 4 times the stall speed gives 'fighter-type' performance and extended vertical aerobatics." Why did you use a Li-Poly battery in Example 1 when this is an article about using 3S "A123" 2300mAh packs?      I wanted to illustrate, with the next example, that there can actually be an increase in performance with careful selection of motor and prop when a 3S "A123" 2300mAh pack is used in the same application. Example 2: parkzone T-28 with Scorpion SII-3014-1200 motor, Master Airscrew 10x8 G/F 3 series prop and 3S "A123" 2300mAh Battery Ready to Fly (RTF) weight: 37 oz. Wing area: 315 sq.in. (315 sq.in. / 144 sq.in. (1 sq.ft.) = 2.1875 sq.ft.) Prop: Master Airscrew 10x8 G/F 3 series (pitch 8 inches) Measured RPM: 9,017 Wing loading: 37 oz. / 2.1875 sq.ft. = 16.914286 oz./sq.ft Pitch Speed: (8 * 9017) / 1056 = 72136 / 1056 = 68.310606 mph Stall Speed: SQRT(16.914286) * 3.7 = 4.1126981 * 3.7 = 15.216983 mph Pitch Speed to Stall Speed Ratio: 68.3 mph / 15.2 mph = 4.4934211 or about 4.5:1 Drive Calculator (Vopt) 52.7 mph. 52.7 / 15.2 = 3.5:1      The math demonstrates that there is better performance available and so does the actual in flight performance! Return to Introduction Some Examples of Appropriate Airframe Selections      The motor/prop tables suggest that the appropriate usage of a 3S "A123" 2300 pack ranges from about 200 watts in to a bit above 300 watts in depending on the motor and prop selected.      There is really no "one" correct size or weight of airframe to use with the 3S "A123" 2300mAh pack, but some practical examples can be a guide to a successful plane.      I have four trainer, sport, sport scale planes currently flying using these packs. The data for the parkzone T-28 Trojan as flown with a 3S "A123" 2300mAh pack and stock motor is also included for reference.

Plane	Type	Motor	Prop	Wing Area sq.in.	RTF wt. oz.	Watts In/ lb.	Wing Loading	Wing Cube Loading	Pitch Speed mph	Stall Speed mph	Pitch Speed to Stall Speed
Model Tech Fledgling Gen-II	Shoulder wing trainer/sport	TowerPro 3015-7	APC 12x8E	469.5	40.3	111.2	12.36	6.85	52.5	13.0	4.04:1
parkzone T-28 Trojan	Low wing Trainer/Scale	parkzone 480	MA std. wood 11x8	315	34.67	84.5	15.85	10.72	46.1	14.7	3.14:1
parkzone T-28 Trojan	Low wing Trainer/Scale	Scorpion SII-3014-1220	MA 10x8 G/F 3 Series	315	37	126.3	16.9	11.44	66.6	15.2	4.38:1
Scratch-built Son of Swallow	Low wing sport	Scorpion S-3020-11Turn special wind	MA 10x8 G/F 3 Series	415	41.34	124.6	14.34	8.45	67.5	14.0	4.82:1
Scratch-built Fusion 380	Low wing sport	Hyperion Z-3019-10	MA 10x8 G/F 3 Series	375.5	39.78	122.6	15.25	9.45	66.0	14.45	4.57:1

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