The performance difference between air crew drill and mud motor was analyzed under the air drilling condition.

对比分析了空气螺杆钻具与泥浆马达在空气钻井井况下的性能差异。

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The 4, 200 passengers and crew on board had not conducted an emergency drill after leaving on its cruise several hours earlier.

BBC: Costa Concordia cruise ship captain 'went off course'

At 10:30 a.m. a drill consisting of lowering a lifeboat with crew members aboard began.

WSJ: Cruise Ship Lifeboat Accident Kills Five in Spain