5 ms·
You’ll be interested to read about aspect ratio: https://en.wikipedia.org/wiki/Aspect_ratio_(aeronautics) https://en.wikipedia.org/wiki/Aspect_ratio_(aeronautic
by kgilpin 8y ago
You’ll be interested to read about aspect ratio: https://en.wikipedia.org/wiki/Aspect_ratio_(aeronautics) https://en.wikipedia.org/wiki/Aspect_ratio_(aeronautics)
As the ratio of the span to the chord increases, the ratio of lift to drag increases as well.
The drag of an object in the sense of forcing its way through the air (eg a semi truck on the highway) is important, but for airplanes there is also a very important phenomenon of drag due to lift (“induced drag”). It’s kind of non-intuitive. But if you’ve ever seen those strong vortices coming off a wingtip, you’re seeing induced drag. Think of the energy creating this: https://youtu.be/uXrnGiIMGLs https://youtu.be/uXrnGiIMGLs
It’s energy created by propulsion but turned uselessly into spinning air.
- phumbe 8y agoYou beat me by two minutes on the aspect ratio bit :) Here's another good video showing wingtip vortices: https://www.instagram.com/p/BhzCLgFnVzL/?hl=en&taken-by=edseguin https://www.instagram.com/p/BhzCLgFnVzL/?hl=en&taken-by=edse... Not sure what you mean by "energy created by propulsion." The vortices result from low pressure on top and high pressure below making the air want to curl around. That imparts downwash on the wing, reducing its effectiveness.
- kgilpin 8y agoI mean that the airplane’s propulsion system is ultimately the power source behind those vortices, by forcing the wing through the stationary air.