UPDATE: 28th BW conducts final pre-season motorcycle mass briefing Published March 31, 2016 28th Bomb Wing Safety Office ELLSWORTH AIR FORCE BASE, S.D. -- The make-up motorcycle pre-season briefing will now be held April 13 from 3 to 4:30 p.m. in the Deployment Center Auditorium. Riders who did not attend the briefing last week are encouraged to attend this last mass briefing. For more information, call Staff Sgt. Kenneth Hill, 28th Bomb Wing occupational safety technician, at (605) 385-7233, or Master Sgt. James Blair, South Dakota Air and Space Museum curator, at (605) 385-5188.