Aerowerx
Well-Known Member
I ran across an interesting paper on optimizing the lateral stability of a pure flying wing. It can be downloaded from this web site.
The method they use is to divide the wing into 3 sections on each half-span, and then tweak the dihedral in each section. Negative values (anhedral) is allowed. The goal being to meet the requirements of MIL-F-8785C.
Here is a 3-view of what they came up with, snipped from the paper:
And an RC model they built
Kinda cool looking, isn't it?
This model has dihedral angles of -6, -2, and +10 degrees. Note that the +10 is only at the very tip of the wing.
Then I came across another paper by the same group that goes into more details on the math used. It also defines a method of creating a "satisfaction factor" for judging how well it meets MIL-F-8785C.
And what I find most interesting about this is that the group that did this work is located in Beijing, China, and they site a US Mil Spec. Not to many decades ago this would have been unheard of. At least they would not have mentioned it.
The method they use is to divide the wing into 3 sections on each half-span, and then tweak the dihedral in each section. Negative values (anhedral) is allowed. The goal being to meet the requirements of MIL-F-8785C.
Here is a 3-view of what they came up with, snipped from the paper:
And an RC model they built
Kinda cool looking, isn't it?
This model has dihedral angles of -6, -2, and +10 degrees. Note that the +10 is only at the very tip of the wing.
Then I came across another paper by the same group that goes into more details on the math used. It also defines a method of creating a "satisfaction factor" for judging how well it meets MIL-F-8785C.
And what I find most interesting about this is that the group that did this work is located in Beijing, China, and they site a US Mil Spec. Not to many decades ago this would have been unheard of. At least they would not have mentioned it.
