He is a substantial investor in Thermion.

Mr. Rolls said yesterday that he was resigning to become the president and chief executive of Thermion Systems International, a company that holds patents with aerospace and commercial applications.

John A. Rolls, the chief executive of Thermion Systems International and a former president of Deutsche Bank North America, was injured Monday afternoon when the single-engine airplane he was piloting crashed at the Danbury Municipal Airport in Connecticut.

His father, who retired as the chief executive of Deutsche Bank North America in New York, is now the chief executive of Thermion Systems International in Bridgeport, Conn., a manufacturer of surface heating devices for aerospace and other industrial uses.