I'm no engineer, but I do understand that there is a pretty significant drag penalty associated with round tubing hanging out in the air flow. So let's assume for a moment that there is a biplane design that uses round aluminum tubing for cabane and interplane (N) struts. And let's assume that you wonder if streamlined struts might be a better idea, to reduce drag to some degree.
- How would one go about calculating the specs for either streamlined aluminum tubing, or wood, that would replace the round tubing with equivalent or better strength?
- How would one calculate the difference in drag force between round and streamlined sections, to decide if it's even worthwhile to make the change?