This is a small part of the obituary that documented his remarkable life:
Before, during and after his career as volcanologist, C. Dan Miller loved to fly. Not only was Dan a superb pilot, he was also a highly gifted craftsman who took great pride in the restoration of a classic Bücker Jungmann biplane, which he completed while living in Denver. Dan taught himself aerobatics in the Bücker and became accomplished in this demanding skill. After retirement, he built not one, but two high-performance aerobatic RV-8 airplanes, one for himself and another for USGS colleague Dave Harlow. He loved taking his friends up for flights, treating them to as much aerobatic thrill as they desired but no more than they felt comfortable with. He also joined a local formation flight team that performed in the Portland area, as well as at the international Experimental Aviation Fly-In at Oshkosh, Wisconsin. In 2019, the FAA honored Dan with the Wright Brothers Master Pilot Award, which recognizes individuals who have exhibited exemplary aviation expertise, distinguished professionalism, and steadfast commitment for at least 50 years of piloting experience.
Hank