what does "tied down" mean? That was at approximately :45 P.M. Johnson was then firmly in control. In their early moments aboard, however, Youngblood had continued to act as his Ken O'Donnell, with Emory Roberts and agents of the Vice Presidential detail as his staff. Explaining that he himself would be tied down in the stateroom, Youngblood told Lem Johns to identify Vice Presidential advisers for the crew, order the stewards to draw up a passenger manifest, and delay the plane's departure until the arrival of the Kennedys.