Don Cummins: From twice-fired machinist to Vice President of Engineering

Donovan 'Don' Cummins started contributing to the family business as a teenager, even before officially joining the payroll in 1922. He learned by doing, working alongside his brothers Clessie and Deloss. Despite family ties, Don was fired twice as a teenager for machining mistakes, but the experiences under Clessie's exacting standards shaped his career.

During the 1920s and 1930s, Don became deeply involved in engineering and testing that helped establish Cummins diesel engines. He assisted with engine preparations for demonstration vehicles used in stunts during the Great Depression. One notable contribution came in 1931 at the Indianapolis Motor Speedway, where Don performed repairs on a moving diesel truck, fixing steering and crankshaft seal problems without stopping the vehicle.

In the early 1950s, Don was instrumental in Cummins' return to racing. The 1952 Indianapolis 500 effort featured a diesel-powered race car that won the pole position and tested the Cummins PT Fuel system. In 1956, Don led the effort to establish Cummins' first overseas plant in Shotts, Scotland, serving as managing director.

By the mid-twentieth century, Don had become a researcher, development engineer, racing contributor, and international pioneer. His career culminated in his appointment as Vice President of Engineering, a remarkable rise from a twice-fired machinist to one of the most influential engineering leaders in Cummins history.