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Toshiba sacked Westinghouse Electric's chairman two days before the U.S. nuclear engineering subsidiary filed for bankruptcy protection last week, as the Japanese firm tries to draw a line under the travails of a business that has cost it billions of dollars. A spokesman for Toshiba said Danny Roderick was replaced as Westinghouse's chairman by Mamoru Hatazawa, chief of Toshiba's nuclear division, on March 27, two days before the Chapter 11 filing. Hatazawa's role would be temporary, he added. Roderick, described by industry and company insiders as more salesman than engineer, was the driving force behind Toshiba's nuclear ambitions. Toshiba said the executive change, only the second to be made at the top level since the Westinghouse crisis began to unfold in December, was intended to reassure clients in advance of the bankruptcy filing. Shigenori Shiga, a former Westinghouse boss, resigned as Toshiba's chairman earlier this year. Calls to Roderick seeking comment went unanswered.

A source familiar with the matter said Jeffrey Benjamin, responsible for delivering on new power plant projects had also left. Benjamin did not immediately respond to a request for comment. Benjamin, a veteran nuclear engineer, was appointed in 2013. According to the Westinghouse website, new projects now fall under David Durham, a former GE Hitachi Nuclear Energy executive, who joined Westinghouse in 2015. A spokeswoman for Westinghouse said the decision to remove Roderick had come from Toshiba. "The action was completed by Toshiba in their role as parent company," she said, declining to comment on other executive departures. Roderick joined Pittsburgh-based Westinghouse as chief executive from a nuclear joint venture of General Electric and Hitachi. He took up his role in September 2012, a year after Japan's Fukushima disaster hit the industry.