US Coast Guard Gulfstream V / C37A. The USCG operates two long-range Gulfstream V as its principle Command and Control transport for travel by the Secretary of Homeland Security, the Coast Guard Commandant, and other U.S. officials. On long flights, the C-37A can carry 12 passengers and a crew of four going Mach .80 at 51,000 feet cruising altitude, all with considerable fuel efficiency. Model by HTAI. By Tom Wilson.