How to solve for bending moment?

[airstrike_ola]

Hello, I'm a newbie here, please help me to solve for the bending moment of my design airplane. I want to know if my wing spar is strong enough to support the weight of my design which is 490 lb. I want also to know if what is the breaking point of the wing spar. Please see the attached picture.

Thank you...

 

[minger]

You can assuming that your beam is simply supported at the wing tips, with a point load at the center, and then just either simply compute the bending moments in your beam. The stress is then just
$$\sigma = \frac{My}{I}$$

Or I'm sure a decent google result will give you the closed form solution given your geometry.

 

[NatSusan]

Hi there, welcome to the forum! It's great to see new members interested in designing and building airplanes. In order to determine the bending moment of your design, you will need to use some basic engineering principles and calculations. First, you will need to calculate the total weight distribution of your airplane, including the weight of the wing spar itself. Then, using the distance from the center of gravity to the wing spar, you can calculate the bending moment.

As for the strength of your wing spar, it's important to use the appropriate materials and dimensions to ensure it can support the weight of your design. You can consult with a structural engineer or use online resources to determine the maximum load your chosen materials can withstand. It's also a good idea to build in a safety margin to account for any unexpected stresses or impacts.

As for the breaking point, it's difficult to give a specific number without knowing the exact specifications of your design and materials. However, it's important to regularly test and inspect your wing spar during the building process to ensure it is strong and secure.

I hope this helps get you started in your calculations and design process. Good luck with your project! And don't hesitate to ask for further assistance or advice from the community here. We are all passionate about airplanes and happy to help.