Just throught I'd throw this out there, received it in a school email. Per the email it is available online. http://graduateschool.und.edu/_files/docs/2011-factsheets/aerospace-studies-phd-4-12.pdf
Online doctorates from traditional B&M universities are hard to come by. I find it odd that when one finally does offer an online doctorate, it is in a highly technical, less popular, field.
Embry-Riddle Aeronautical University also offers a Ph.D. in Aviation with three six-day residencies. UND has been planning their offering since at least January 2009. Great to see it, well, off the ground!