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  #16  
Old 08-27-2018, 09:40 PM
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Wow I feel Like this build is going over horribly. So should I do something else off this list or perhaps a different bomber that has not been done yet?
Stick with it +1,000,000.
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  #17  
Old 08-29-2018, 09:54 AM
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Custom prop
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  #18  
Old 08-29-2018, 12:16 PM
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three racks of 28 not 25 and two sets of 12 on the wing racks for sequential 108. I know I will have to reduce the aerodynamic load to about 20% (estimate) on the sim on the bombs in the bombbay to keep rf from "chugging" at a low fps from physics calculations.
108 sequential bomb drops, glad I don't have to program that lot.

The custom prop looks great.
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  #19  
Old 09-11-2018, 03:39 PM
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general RC electric question. What duty cycle percentage can I run batteries at before heating becomes an issue? ex. right now on takeoff the b-52 is pulling 688 amps in total and 250-400 amp total at cruise and the battery continuous amp cap is 2,904 with the burst amps 5280.

Am I in the clear to mount the batteries in the top of the fuselage or do I need to stuff them in the nacelles for airflow?
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  #20  
Old 09-12-2018, 01:33 PM
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right now I am on the fence about keeping the edfs or changing to turbines (Wren 44's)
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  #21  
Old 09-14-2018, 01:16 PM
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flaps cut, spoilers ready



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File Type: jpg B-52 Build Pic 06.jpg (37.1 KB, 89 views)
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  #22  
Old 09-14-2018, 06:31 PM
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right now I am on the fence about keeping the edfs or changing to turbines (Wren 44's)
Hmmm, the sound of the turbines fits any jet better than the edfs IMHO
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  #23  
Old 09-15-2018, 08:02 AM
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Hmmm, the sound of the turbines fits any jet better than the edfs IMHO
The B-52 is big enough to just put speakers plane. Oh.. two custom TF-33 sound (jet and fan) profiles will be included.
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  #24  
Old 09-15-2018, 10:05 AM
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Originally Posted by legoman View Post
general RC electric question. What duty cycle percentage can I run batteries at before heating becomes an issue? ex. right now on takeoff the b-52 is pulling 688 amps in total and 250-400 amp total at cruise and the battery continuous amp cap is 2,904 with the burst amps 5280.

Am I in the clear to mount the batteries in the top of the fuselage or do I need to stuff them in the nacelles for airflow?
In the real world, I think you'd tend towards cells being in some parts of the wing.
688/8= 86A and that would be a lot of voltage drop running wires from the fuselage. More cells would also help with that.
It's also a trade off, as more mass in the wing effects roll and more root strength is needed. While the B-52 is not aerobatic, I have learned from flying the Craze the roll and strength to weight ratio benefit of lowering the mass as you go from root to tip.



While was not yet ready to fly, large EDF B-52s can be done:
https://www.youtube.com/watch?v=0iVbzYCHFPY


Less fire than fuel in event of a crash (sorry UT )
https://www.youtube.com/watch?v=YAWwe474YHk
Yes, LiPolymer cells can also burn if puntured. Battery or fuel, it depends on the characteristics of the crash.

With proper design, EDFs (especially larger units/planes) can do very well in making realistic turbine sounds
https://www.youtube.com/watch?v=QgW1LRio0iU

https://www.youtube.com/watch?v=qvWGDk1htjw
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Last edited by Fly_electric; 09-15-2018 at 10:16 AM.
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  #25  
Old 09-15-2018, 11:19 AM
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Quote:
Originally Posted by Fly_electric View Post
In the real world, I think you'd tend towards cells being in some parts of the wing.
I have considered wing mounts. But I am still worried about internal air and battery temperature.

Quote:
Originally Posted by Fly_electric View Post
688/8= 86A and that would be a lot of voltage drop running wires from the fuselage. More cells would also help with that.
It's also a trade off, as more mass in the wing effects roll and more root strength is needed. While the B-52 is not aerobatic, I have learned from flying the Craze the roll and strength to weight ratio benefit of lowering the mass as you go from root to tip.
I am not worried about extra weight from cells to compensate for voltage drop. It has enough Lift to handle the bigger batteries. Although the roll rate is a minor concern.
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  #26  
Old 09-17-2018, 03:33 PM
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Forget the EDFs I looked at the wire needed to run 80+ amps to AND from the motors. and we are looking at 4 gauge minimum, 2 gauge for the outers with the potential for needing 0 gauge if you are not careful with the ramp up. And did I mention I need 8 wires running in each wing, TOO MUCH weight for me. Turbines here I come.
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  #27  
Old 09-17-2018, 04:48 PM
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Did not catch what the size and weight are in the physics, but if on the high side, turbines are probably the right choice. 0 gauge is getting into welding cable land, and I'd doubt anyone flies with that weight.

Larger weight EDF here, but of course, no motors in the wings:
http://old.neumotors.com/NeuMotors/EDF_motors.html
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  #28  
Old 09-17-2018, 05:15 PM
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Originally Posted by Fly_electric View Post
Did not catch what the size and weight are in the physics, but if on the high side, turbines are probably the right choice. 0 gauge is getting into welding cable land, and I'd doubt anyone flies with that weight.

Larger weight EDF here, but of course, no motors in the wings:
http://old.neumotors.com/NeuMotors/EDF_motors.html
Eighth scale is what I am shooting for. 8x 120mm edfs is what I was using and the only dimension I can increase is the number of blades and volts applied.
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  #29  
Old 10-24-2018, 04:11 PM
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Though I would post a picture or two of the flaps down. I have rebuilt them multiple times to try and get the wing right
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File Type: jpg B-52 Build Pic 07.jpg (7.4 KB, 15 views)
File Type: jpg B-52 Build Pic 08.jpg (25.3 KB, 14 views)
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  #30  
Old 10-26-2018, 11:21 AM
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hello lego can u please do it
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