A.the shafting’s vertical vibration
B.violent friction and sea water corrosive
C.friction and high temperature
D.violent friction and high temperature

A.the border flange’s excursion and flection
B.the both end shafts line’s accordance
C.the border flange’s flection and the both end shafts line’s accordance
D.the border flange’s accordance and both end shafts flection degree

A.the stopping engine suddenly
B.the sailing astern and changing direction suddenly
C.the sailing from the shallow water area to the deep water area
D.the ship’s trim too much

A.after the thrust power is zero
B.after the torsion is zero
C.surpass the critical point on the water turbo phase
D.after the speed is zero

A.rapid reduction of ship’s friction force
B.shaft system over mechanical load
C.sharp growth of the torque of diesel engine
D.propeller torque change along J=0 curve

A.reduce the fuel feeding of main engine of inner propeller
B.reduce the fuel feeding of main engine of outer propeller
C.firstly reduce the fuel of main engine of inner propeller, then reduce the fuel feeding of engine of outer propeller
D.reduce fuel feeding of two engines at the same time

A.stop main engine immediately
B.ask the captain and the chief engineer’s permission for stopping the engine
C.initiatively inquire the bridge for the situation
D.stop engine and inform bridge

A.10%
B.15%
C.20%
D.5%

A.cleaning fuel oil, lubricating oil and seawater filter
B.reducing fuel feeding of the main engine appropriately or reducing the pitch angle of propeller
C.using low sea chest
D.closing the skylight and the ventilation opening, which doesn’t affect the normal work of equipments

A.navigating with a low diesel engine speed
B.navigating with a stable diesel engine speed
C.increasing the efficiency of propeller
D.increasing fuel injection

A.prevent the diesel engine surging
B.prevent governor from being damaged because of swing
C.reduce the probability of the crank shaft being torsional vibrated and resonated
D.prevent the main engine being overload or overspeed