He retired from active naval service on July 1, 1990, following completion of a four-year term as CNO.

In May 1986, Trost was nominated by President Ronald Reagan to succeed Admiral James D. Watkins as Chief of Naval Operations (CNO).

[8][9] Trost was recognized as a distinguished graduate of the United States Naval Academy and also served on the board of directors of the Alumni Association, as well as President of the Class of '53.

A classmate and another past President of the Class of '53 was the late Texas businessman and former presidential candidate H. Ross Perot.

He served as Chairman of the Board of the United States Naval Academy Alumni Association in a term that ended in Spring 2009.