Back radius

I got set of 14fret tenor plans from Geargia Luthier supply.
Very detailed plans except for the back radius It seems greater than 15 foot they have no contact number so if any one knows what it might be that would be great thank you

12' or 15'.it's not going to make any difference. They are both commonly used. Just use what you have, and match your bracing to the curve as best you can. With many of us builders using shop made dishes and cauls, the numbers are only relative anyway. No rocket science involved!

Thank you Bob