Three Decades of In Situ Observations Inside Thunderstorms

The South Dakota School of Mines and Technology armored T-28 aircraft began research flights in 1970, and became fully operational in support of the National Hail Research Experiment in 1972. Between 1972 and 2003 it participated in more than two dozen cooperative field programs focussed on convective storm phenomena. In situ observations in hailstorms in northeastern Colorado, Montana, Switzerland, and Alberta contributed fundamentally to the understanding of how hail develops. Beginning in the 1980's the aircraft became a valuable tool for verifying polarimetric radar signatures from various classes of hydrometeors in convective storms, furthering understanding of precipitation , particularly hail, development, in these storms. Combinations of in situ hydrometeor instrumentation as well as a gas analyzer for tracer studies were employed in these studies. In the 1990's its capabilities for electrical observations were developed to support fundamental research into convective storm electrification. The aircraft is being retired from service in 2004, but leaves a rich legacy of unique observations to aid researchers in their continued quest for greater understanding of convective storm phenomena.