Bismarck Gate closure Published May 4, 2011 By 28th Security Forces Squadron ELLSWORTH AIR FORCE BASE, S.D. -- The Bismarck Gate, personal vehicle inbound lane, will be closing May 5 at 1 p.m. for mandatory maintenance. All personal vehicles should proceed to the Patriot Gate for access to Ellsworth Air Force Base. The Bismarck Gate is scheduled to reopen May 6 during normal hours of operation.