U.S. striving to detect diesel submarines The Navy is concentrating its efforts to find the quiet, difficult-to-detect crafts in Asia and the Pacific region. Eric Rosenberg Hearst Newspapers Last update: July 08, 2006 – 11:00 PM WASHINGTON - The U.S. Navy is stepping up its program for detecting new diesel-powered submarines that are extremely quiet, hard to find and increasingly relied upon by China, Iran and North Korea.