Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. US Senators Point to 'Hypersonic Gap' With Russia, China Eunjung Cho U.S. senators are concerned Russia and China may outpace Washington in developing hypersonic weapons. In a Senate Armed Services Committee hearing Thursday with top defense officials, lawmakers expressed concern about the weapons that fly at five times the speed of sound, or Mach 5. Democratic Senator Richard Blumenthalof Connecticutcalled the hypersonic weapons "a game-changer." Independent Senator Angus Kingof Mainecalled them "a nightmare weapon for aircraft carriers." "It sounds to me as if hypersonic weapons and other future weapons have been more advanced by other countries such as China, even Russia coming back into the scene in a real aggressive way'¦ are we going to deter them from moving forward?" asked Democratic Senator Joe Manchinof West Virginia. .