Conversation so far:
How did Chesley Sullenberger begin his military service?
Chesley Sullenberger was appointed to the United States Air Force Academy, entering with the Class of 1973 in June 1969.
What was Chesley Sullenberger's area of study?

Question: What did he do after he got his master's degree?
Self-contained rewrite: What did Chesley Sullenberger do after he got his master's degree at Purdue University?