LOS ANGELES – An ex-Boeing Co engineer, found guilty last year of passing space shuttle secrets to China in America’s first conviction under a 1996 espionage law, was sentenced on Monday to 15 years in prison.

Dongfan “Greg” Chung, a naturalized U.S. citizen, was convicted in July of economic espionage and acting as an agent for the People’s Republic of China.

In sentencing Chung to 188 months behind bars, U.S. District Judge Cormac Carney, who presided over the 10-day trial in Santa Ana, California, said he wanted to send a signal to China to “stop sending your spies here,” according to prosecutors.

Chung, 73, the first person convicted at trial under the Economic Espionage Act, told the judge he was innocent.

“Your honor, I’m not a spy, I’m an ordinary man,” he said. “I was planning to write a book. Those documents were going to be used for my references.

NASA’s plans to return astronauts to the moon are dead. So are the rockets being designed to take them there — that is, if President Barack Obama gets his way.