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Flashcards in Test 1 Deck (56)
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1

How many hours of rest in a 24 hour period?

10

2

How many hours of rest in a seven day period?

77

3

Hours of rest may be divided into no more than

Two periods in a 24 hour period, one of which must be at least six hours

4

Intervals between consecutive periods of rest must not exceed

14 hours

5

The external force applied to the Gyro to change its plane of rotation resulting in the Gyro moving perpendicular to the application of the applied force is known as what?

Precession

6

What is a lubbers line?

The fixed line on a compass binnacle pointing towards the front of the ship and corresponding to the centerline of the vessel

7

What do you do in the event of a Gyro failure?

Inform the master
Switch to hand steering
Use magnetic compass or other means for heading indication
Consider the effects on other Navaids
Inform the engine room
Inform the officer responsible for general maintenance
Plot your position
Advise pilot if one is a board
Determine compass error as soon as possible

8

What Sends the Gyro signal to the repeater?

The transmitter

9

What adjustments are made to the auto pilot?

Rudder adjustment, weather adjustment, rudder limit, speed, load (light or loaded)
AB’s do not generally adjust, mates should adjust

10

What are the steering gear test requirements per SOLAS?

During stays in Port between voyages or passages a test to be carried out within 12 hours of the estimated time of “standby departure”

11

What is sent from the steering stand to the steering system?

An electrical signal

12

Even in the case of an electric hydraulic steering system, what moves the rudder ?

Hydraulics

13

Hard starboard or port =

35°

14

Full rudder =

30°

15

What are potential causes for steering failure?

Loss of control of the steering stand
Loss of steering pump on the steering stand
Failure of the steering pump in the steering gear room
Complete loss of diesel electric power
Physical loss of rudder
Not a Gyro failure

16

What are the procedures for steering failure?

Inform the master
Inform the engine room
Advise pilot if one is a board
Check for power failure or other indicated alarm condition
Modify the AIS status message to communicate relevant information
Make appropriate sound signal in restricted visibility

17

How do you operate the radar if your Gyro fails?

Head up

18

Explain how a radar works

A transceiver sends a pulse modulated signal out, measures the time until the signals return, determines distance from this, and can display the returns in a directionally accurate presentation because of the use of a directional antenna

19

What gives the best radar return echoes?

Large targets
The aspect of the target
The texture, smoother surfaces offer better reflection
The composition, steel has good, wood and fiberglass offer little reflective composition

20

Explain how the Doppler speed log works

it receives a reflective signal returning from the sea bed. The maximum efficiency to 600 feet over the ground. It also receives reflected signal from particles suspended in the water. It registers change in frequency, not time, to measure speed

21

What does the Fathometer indicate?

The depth of the water under the keel

22

The speed of sound through the water is approximately

4800 ft./s

23

Explain how a fathometer works

The Oscillator creates an electrical signal at the desired frequency. Then the transducer converts the electrical signal into ultrasonic vibrations for transmission and sends the depth indication back to the indicator unit

24

CFR regs apply to who?

US vessels and vessels in US waters

25

Give sources of error with the Doppler speed log

Transducer orientation (pitching and rolling)
Vessel motion error (vibration)
Velocity of sound error (changes in water temp or salinity)
Signal loss error (attenuation of sound in the water or bottom)

26

What does the Doppler speed log give?

The speed of the vessel over ground and threw the water

27

The speed of sound through the ocean water is nearly always

Faster than the speed of calibration for the Fathometer

28

What factor has the greatest effect on the amount of gain required to obtain a Fathometer reading?

The type of bottom

29

When operating over a muddy bottom, a Fathometer may indicate

2 depth readings

30

The recording Fathometer produces a graphic record of the

Depth underneath the keel against a time base