Propeller pitch speed minus ship speed divided by the propeller pitch speed is termedA.app

A controllable pitch propeller on a diesel driven vessel eliminates the need for

A.friction clutches

B.disconnect clutches

C.reversing gears

D.reduction gears

A.apparent slip

B.true slip

C.pitch

D.propulsive efficiency

Compared to a constant pitch propeller, a controllable pitch propeller

A.more efficiently uses available engine power

B.operates at a lower efficiency at a fixed speed

C.produces the same torque at lower engine power

D.develops its rated power at a lower speed

A.An external mechanism

B.An internal mechanism

C.An interlock device

D.A hunting gear system

A．the extra weight required for the diesel reduction gearing

B．a minimum speed for the engines that limits the minimum speed of the vessel

C．the higher fuel consumption per SHP

D．the low efficiency of the system when a controllable pitch propeller is used

A large vessel is equipped with a controllable pitch propeller. Which statement is TRUE？

A.When dead in the water，it is often difficult to find the neutral position and slight headway or sternway may result

B.When going directly from full ahead to full astern，there is complete steering control

C.When the vessel has headway and the propeller is in neutral，there is no effect on rudder control

D.When maneuvering in port，full ahead or astern power can usually be obtained without changing shaft RPM

材料：

During the morning of 2 August 1999 the supply vessel Putford Worker was working cargo at installations in the North Sea. She had completed operations at one installation without incident．

At 1110 she approached the second installation and carried out precautionary engine and steering tests．These were satisfactory，and at 1115 the vessel was in position to work cargo．The master was on the bridge at the joystick control；the weather was fine and the sea calm． The first lift was a 10&39; x 8&39; container．The deck crew attached the hook of the installation&39;s crane to the container，and moved forward to a safe position．The master then noticed that the vessel was moving forward out of position and moved the joystick to counteract the ahead movement．He then saw that the port propeller was indicating full ahead pitch，so changed from joystick to manual pitch controls and promptly put them to full astern．

This did not prevent the vessel moving ahead so far that the attached container be dragged over the stern and into the sea. Placing the manual pitch controls to zero then caused both propellers to return to neutral．Control of the vessel was regained，and the problem did not immediately re-occur．

Later tests and inspections by specialist control engineers and the propeller manufacturers showed no fault with the control systems or the port propeller．However，some wear was found in the feedback linkages on the control system of the starboard propeller．This was rectified，and manoeuvring tests completed satisfactorily．

问题：

In this passage the supply vessel is ________．

A.one that supplies fuel oils to other deep sea vessels

B.one that supplies stores to other deep sea vessels

C.a tug boat

D.smaller container vessel

The joystick is a device ________．A.controlling rudders

B.controlling shore cranes

C.controlling the operation of cargoes

D.controlling the propellers

On noticing that the vessel was moving forward out of position，the master ________．A.moved the joystick forward to go together with the ahead movement

B.moved the shore crane to go aftward

C.made the container move aftward by operating the joystick

D.operated the joystick to control the vessel and move her aftward

It is clearly demonstrated that ________．A.the testing of engines and steering before working cargo at an installation is an important precaution

B.the testing of engines and steering before working cargo at an installation was not followed by Putford Worker

C.there is no value of moving the deck crew clear once a lift is attached

D.had the deck crew not bothered to move clear from，the consequences could have been avoided

请帮忙给出每个问题的正确答案和分析，谢谢！

Kort nozzles are installed around the propellers of some vessels to ______.

A.increase the thrust of the propeller

B.protect the propeller from striking sawyers

C.protect the propeller from striking barges towed on the hip

D.protect the propeller from touching bottom in low water

propeller shaft 意思是传动轴。()

The circular steel structure installed around the propeller of a towboat is the______．

A.nozzle

B.shroud

C.strut

D.Hood