ZAPF, NORMAN F. (14 July 1911-23 June 1974), a mechanical engineer whose research in streamlining led to the design and construction of streamlined locomotives, was born in Cleveland to Herman R. and Mabel (McNess) Zapf. He entered Case School of Applied Science, studying aerodynamics under Dr. Paul Hemke. As an undergraduate, Zapf used the recirculating-type wind tunnel at Case and scale models of steam locomotives to achieve a practical streamlined design that reduced drag 90-100%. At 75 mph, his version required 350 hp less than the unstreamlined form. The findings were part of his senior thesis, "The Streamlining of a Steam Locomotive." He graduated in 1934 with a B.S. degree in mechanical engineering and took a job with New York Central Lines, but eventually resigned when he failed to procure an engineering position. He returned to Case as a graduate student but soon left to work for a Boston firm that produced hardware for locomotives. In the 1930s, railroads were searching for ways to improve their image while reducing costs in view of competition from airplanes and automobiles. New streamlined diesel-electric locomotives were introduced, but most railroads already had enormous investments in their steam locomotives. Conclusions from Zapf's thesis were used by New York Central Lines in the design for their Commodore Vanderbilt, the company's first streamlined steam locomotive. Zapf served in the Coast Guard during WORLD WAR II and afterward moved to Florida, where he and his family developed Zapf Groves, Inc.
Zapf married Mildred Anderson in 1935; they had four children: Frederick, Douglas S., Shirley, and Laura. He died in Veno Beach, Florida and was buried there.