YUMA, Ariz. — A U.S. Army private has been charged with trying to sneak a small amount of military explosives on board a United Airlines flight from Arizona to Los Angeles, authorities said Thursday. Pfc. Christopher Eric Wey, 19, was detained Wednesday after Transportation Security Administration screeners at the airport in Yuma found about a half-ounce of military explosives in his bags, according to a federal criminal complaint. He was arrested and charged Thursday with attempting to carry an explosive onto an aircraft and transporting a stolen explosive, said Robbie Sherwood, a spokesman for the U.S.