Concerns raised about gaps in airline and tour bus safety . The FAA has been criticized for not doing enough to protect passengers from the effects of turbulence. Leading U.S. safety advocate especially concerned about tired tour bus drivers . Regulators defend bus safety oversight , say government acts when it uncovers problems .
Concerns raised about gaps in airline and tour bus safety . Issue gains prominence with focus on 787 fires , two deadly bus crashes . Leading U.S. safety advocate especially concerned about tired tour bus drivers . Regulators defend bus safety oversight , say government acts when it uncovers problems .