How can ı increse flight time - CMP T-34 Mentor
07-09-2009, 05:47 AM
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How can ı increse flight time - CMP T-34 Mentor
ı finished my T-34 Mentor 46 CMP airplane with electric motor and tested it ıt flies well but flihgt time is only 4minutes. How can ı increse flight time ? and how can ı calculate flight time ?
my configuration is :
Electric motor : MonsterPower 46 (670kv)
ESC :TURNIGY Sentry 60amp Speed Controller
Battery :
Propeller : 13*10 Electric
So if ı want to increase flight time with adding one more 3700mah 4s 20c battery connected in paralell it becomes 7400Mah 4s 20c.
ı want know if 7400mah battery causes any damage to ESc or electric motor or not ?
my configuration is :
Electric motor : MonsterPower 46 (670kv)
ESC :TURNIGY Sentry 60amp Speed Controller
Battery :
Propeller : 13*10 Electric
So if ı want to increase flight time with adding one more 3700mah 4s 20c battery connected in paralell it becomes 7400Mah 4s 20c.
ı want know if 7400mah battery causes any damage to ESc or electric motor or not ?
07-09-2009, 11:16 AM
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RE: How can ı increse flight time - CMP T-34 Mentor
Change to a 13x6 prop and try again with no other changes, I think you'll be happier with the time that you get.
07-09-2009, 12:11 PM
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RE: How can ı increse flight time - CMP T-34 Mentor
The max flight time you can get out of a battery pack is
FlightTime = BatteryCapacity/CurrentDraw
To first order, your flight time will scale with the battery capacity, so doubling it will give you about twice the flight time. However, more battery weight may mean your plane doesn't fly as well, and/or you need more average power to fly it, so you may not get quite double the flight time out of it.
Calculating your current draw from your batt capacity and flight time gives about 51A current draw.
Using two 3400mAh packs in parallel will give you twice the capacity, 6800mAh (6.8Ah), and probably double your flight time:
FlightTime = 6.8Ah/51A = 0.133h = 8 mins
As DaveFlynn suggested, you can reduce the prop loading and reduce your current to get more flight time as well. Just check your current with the new prop, and plug it into the equation above to estimate your new flight time.
Adding battery capacity (connecting packs in parallel) will not harm your ESC or motor. Adding battery voltage (connecting packs in series) can. The parallel packs just gives you longer runtime, and a higher max current capacity. The motor & ESC will draw whatever current it wants, based on the battery voltage and your prop size/pitch.
FlightTime = BatteryCapacity/CurrentDraw
To first order, your flight time will scale with the battery capacity, so doubling it will give you about twice the flight time. However, more battery weight may mean your plane doesn't fly as well, and/or you need more average power to fly it, so you may not get quite double the flight time out of it.
Calculating your current draw from your batt capacity and flight time gives about 51A current draw.
Using two 3400mAh packs in parallel will give you twice the capacity, 6800mAh (6.8Ah), and probably double your flight time:
FlightTime = 6.8Ah/51A = 0.133h = 8 mins
As DaveFlynn suggested, you can reduce the prop loading and reduce your current to get more flight time as well. Just check your current with the new prop, and plug it into the equation above to estimate your new flight time.
Adding battery capacity (connecting packs in parallel) will not harm your ESC or motor. Adding battery voltage (connecting packs in series) can. The parallel packs just gives you longer runtime, and a higher max current capacity. The motor & ESC will draw whatever current it wants, based on the battery voltage and your prop size/pitch.
