Randall Garrett 
Unwise Child [EPUB ebook] 

After two unsuccessful and seemingly random attempts on his life in the space of as many hours, Michael Raphael Gabriel finds himself called on to act as engineering officer on a new type of spacecraft designed for one mission only, to carry a giant computer to a distant destination before it can destroy the Earth. But once underway he discovers there is a murderer on board and the computer has gone crazy in… Unwise Child!