Cuda airfoils?

[gsjames]

Does anyone have Kevin McKiou's custom airfoil coordinate files for his "Cuda" S8e rocket glider? He named the wing section as a KM7 (8%) and the tail as KM10 (6%). I have obtained a NOS kit but intend to make a copy of the parts so as to preserve the original kit. I am a very experienced RC modeler and have a CNC foam cutter. I also have .dxf "cut files" for the balsa and ply parts.

If I can't find the coordinate files, I'll just substitute some Dr. Mark Drela's DLG sections (of corresponding thickness). Since this design uses balsa-covered white-foam cores and not CNC aluminum molds, the accuracy of the finished wing is probably not that precise anyway.

Thanks in advance for any assistance

 

[gsjames]

I finally found them. Here is the coordinates file. I had to add the .txt suffix in order for me to upload them. Just rename the file as needed for your software.

 

[TheAviator]

If you did want to change airfoils, I've done a comparison of Drela's three low-Re foils. Any of them would likely give you a plane that boosts better and moves better at high speed while retaining most of the min-sink capability of the KM7. They are a fair amount thinner, so care would need to be taken on a structural level.

 

[gsjames]

I didn't actually WANT to change airfoils. I just couldn't find the coordinates file for Kevin McKiou's KM7 section. I even went so far as to contact him and he no longer had the file. I didn't know the camber of the section, only that it was 8% thick and for low Rn's. So, I just chose a Drela DLG section of the same thickness under the assumption that it would close enough given that they were designed for the same operating environment. Remember, this is just a SPORT plane, built for my own personal amusment, and not at attempt at a competition aircraft. Plus, there is NO WAY to be really accurate at this scale and using these building techniques. That's why modern competition models are hollow molded from CNC cut tooling.

 

[TheAviator]

I didn't actually WANT to change airfoils. I just couldn't find the coordinates file for Kevin McKiou's KM7 section. I even went so far as to contact him and he no longer had the file. I didn't know the camber of the section, only that it was 8% thick and for low Rn's. So, I just chose a Drela DLG section of the same thickness under the assumption that it would close enough given that they were designed for the same operating environment. Remember, this is just a SPORT plane, built for my own personal amusment, and not at attempt at a competition aircraft. Plus, there is NO WAY to be really accurate at this scale and using these building techniques. That's why modern competition models are hollow molded from CNC cut tooling.

Fair enough. Have fun!