Help! need help with a good 39" cub Wing!.

Ronsplanes

New member
what kind of a fuselage can I build around a j3 cub wing 40 inches long with a 1000KV motor and a 3S lipo 1300Mah battery weigt 2 pounds? The photo is something Id like to build around the wing, is it possible.
 

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Merv

Site Moderator
Staff member
A 2 pound plane sounds a bit large for the wing. A good rule of thumb is 12 to 15 ounces per square foot of wing area.

The amount of thrust needed from the motor & prop depends on how you want to fly. A slow flying trainer, the thrust will need to be 60-80% of the weight of the plane. A typical plane, 80-100%. A war bird or one with a little zip will be 100-150%. A 3D plane will need 150-200% thrust to plane weight.

Watts per pound is another useful guideline. You'll need to weigh the plane and estimate the weight of the motor and battery.

• 50 to 70 watts per pound is the minimum level of power, good for park flyers and lightly loaded slow flyers.
•70 to 90 watts per pound is perfect for trainers and slow-flying aircraft.
•90 to 110 watts per pound is good for fast-flying scale models and some sport aerobatic aircraft.
•110 to 130 watts per pound is what you want for advanced aerobatics and high-speed aircraft.
•130 to 150 watts per pound is needed for lightly loaded 3D models and ducted fans.
•150 to 210+ watts per pound gives unlimited performance for any 3D model.

Here is a FT thread with more information.

Thrust vs Power to Weight Ratios for Prop Planes