VFR military training routes

VFR (visual flight rules) military training routes

In the United States, routes used by the Department of Defense and associated Reserve and Air Guard units for the purpose of conducting low-altitude navigation and tactical training under VFR below 10,000 ft MSL (mean sea level) at air speeds in excess of 250 knots IAS (indicated air speeds).
An Illustrated Dictionary of Aviation Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved