Thrust needed for Blunt Nose Versa
- Thread starter Robbie
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Theflyingfoam
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http://www.hobbyking.com/hobbyking/...T3511_810kv_Brushless_Power_System_Combo.html
this power system worked great for me!
this power system worked great for me!
1000g is a bit on the heavy side . . .
. . . and since you're asking the question I'm lead to believe that's still lacking the power system, so another 200-400g before you're done . . .
Good rule of thumb is 100W/lb -- this level of power with a reasonable efficiency should give you plenty of thrust to accelerate away from takeoff and when backing down to cruise you should run cool and efficient. Effectively this ratio is good for a "mildly aerobatic" plane, so you should have a good margin of power at this level.
With those weights, you're looking for a power system efficiently outputting 220-300W. On the positive side you can swing a fairly long prop on the blunt-nose -- you're not just limited to 8", which opens up the options quite a bit. On 3S packs, you're looking for a motor capable of running continuous current between 20-27A. On 4S, between 15-20A.
The prop will need to be sized to maximize the draw from the motor at Wide Open Throttle (WOT), and is sized along with the motor's kV.
. . . and since you're asking the question I'm lead to believe that's still lacking the power system, so another 200-400g before you're done . . .
Good rule of thumb is 100W/lb -- this level of power with a reasonable efficiency should give you plenty of thrust to accelerate away from takeoff and when backing down to cruise you should run cool and efficient. Effectively this ratio is good for a "mildly aerobatic" plane, so you should have a good margin of power at this level.
With those weights, you're looking for a power system efficiently outputting 220-300W. On the positive side you can swing a fairly long prop on the blunt-nose -- you're not just limited to 8", which opens up the options quite a bit. On 3S packs, you're looking for a motor capable of running continuous current between 20-27A. On 4S, between 15-20A.
The prop will need to be sized to maximize the draw from the motor at Wide Open Throttle (WOT), and is sized along with the motor's kV.
I use this motor: http://www.emaxmodel.com/views.asp?hw_id=15 with a 9x4.7 prop and a 30A ESC. You can see what I draw here on this short flight and see if it fits your needs:
I lauched at about 70% throttle, flew to altitude at about that same throttle setting, then dropped it down to 50% and cruised around mostly at 30% to test out some new configuration changes on that plane (software mostly). I was quite happy that at the end of the ~6 minute flight, I only used 423mA which left my 3S 3300mA battery at about 12V
I lauched at about 70% throttle, flew to altitude at about that same throttle setting, then dropped it down to 50% and cruised around mostly at 30% to test out some new configuration changes on that plane (software mostly). I was quite happy that at the end of the ~6 minute flight, I only used 423mA which left my 3S 3300mA battery at about 12V
