Not a dramatic blowout, but I've seen two flats on a 4000ft descent into Borrego Springs, CA on the HI-AYH Christmas ride. The first was on a tandem rear wheel where the rim was hot to touch. This was a few years ago. The rear tire went flat quickly, but I don't think there was loss of control.

Last December, I also had a flat on my front tire on that descent. The underlying cause was that the front tube pushed through the rim strip into sharp bits on the rim. Prior to this flat, the front tire had gone thousands of miles without a flat. The rim was warm, but I also believe the extra weight distribution of leaning forward onto the front tire contributed to extra pressure pushing the front tube. Again, the tire went flat quickly, but I didn't lose control as I wasn't going too fast (due to the extra braking).