An engineer convicted of selling stealth technology to China failed to convince the 9th Circuit that the statements he made to federal agents over a week of voluntary interrogations should have been kept out of his espionage trial. The federal appeals court on Monday affirmed Noshir S. Gowadia's convictions and 32-year prison sentence for communicating classified national defense information to the China, illegally exporting military technical data, money laundering, filing false tax returns and other offenses.