Boat Characteristics And Stability

Question 1

Hull construction material

Answer 1

5456 Marine Grade Aluminum

Question 2

Interval between hull frames

Answer 2

30 inches

Question 3

Superstructure Construction Material

Answer 3

5456 Marine Grade Aluminum

Question 4

Highest Fixed Point Location and Height

Answer 4

Radar Antenna

18’ 6”

Question 5

Highest Unfixed Point Location and Height

Answer 5

HF Antenna

28’ 4”

Question 6

Length of the 47’ MLB

Answer 6

Hull - 47’ 11”

Overall - 48’ 11”

Question 7

Beam of the 47 MLB

Answer 7

15’

Question 8

Freeboard of the Bow

Answer 8

6’ 8”

Question 9

Deck Recess Freebord

Answer 9

2’ 2”

Question 10

Stern Freeboard

Answer 10

7’ 1”

Question 11

47 MLB Displacement

Answer 11

40,000 LBS

Question 12

Draft of the 47 MLB

Answer 12

4’ 6” @ the shaft strut extensions

Just aft of the Tow bit

Question 13

How Many Water Tight Compartments Does The 47 MOB have?

Answer 13

7
Lazarette 
Engine Room
Survivors Compartment
Aux 
FWD Compartment
FWD Peak
Enclosed Bridge

Question 14

Secondary Water tight compartments

Buoyancy Chambers

Answer 14

FWD Deck Lockers
Mast Platform
Open Bridge Consoles
Aft Buoyancy Chamber

Question 15

Warning Signs of an Unstable Boat

Answer 15

Determine if it is:

• Listing
• Riding High/Low in the water
• Loaded down on the bow or stern
• Wind and sea conditions
• Compare own boat righting moment with other vessels
• is it damaged?

Question 16

Two types of Stability

Answer 16

Static

Dynamic

Question 17

Define buoyancy

Answer 17

Buoyancy is the upward force of the water being displaced by the hull

Question 18

What is a Keel

Answer 18

The back bone of a boat

Question 19

What angle is the Righting arm of the 47 MLB?

Answer 19

110°

Question 20

Define Set & Drift

Answer 20

Set - Bearing of the current

Drift - Magnitude of the current

Question 21

Bottom plating size

Answer 21

5/16”

Question 22

Side shell size

Answer 22

1/4”

Question 23

Chine plate size

Answer 23

3/8”

Question 24

Hull characteristics

Answer 24

Deep V playing hull

Hard chined hull

Question 25

How many frames on the 47 MLB?

Answer 25

17

Question 26

How many water tight hatches on main deck

Answer 26

5

Question 27

How many QAWTH on the 47 MLB?

Answer 27

2
Fwd comp hatch
Fore peak hatch

Question 28

How many through hull drain fittings?

Answer 28

7

Question 29

Where are the through hull drain fittings?

Answer 29

Question 30

What vents are securable on the 47 MLB?

Answer 30

FWD COMP
ENG ROOM
PORT AFT DECK BOX
STBD AFT DECK BOX

Question 31

What vents are non-securable on the 47 MLB?

Answer 31

Forepeak
Aux
Fuel tank
Laz

Question 32

Max speed & RPM of the 47 MLB?

Answer 32

25 Knots @ 2100 RPMs

Question 33

Most economical cruising speed is between what RPMs?

Answer 33

1800-1900

Question 34

Max range at cruising speed?

Answer 34

200 NM

Question 35

Max endurance of the 47 MLB at cruising RPM? (1850 RPMs)

Answer 35

10 hours @ 1850 RPMS

Question 36

Max crew and passengers?

Answer 36

34 (@ 180 lbs ea.)

Question 37

Max seas/Max surf

Answer 37

30’ Seas

20’ Surf

Question 38

Light surface ice capabilities?

Answer 38

The 47 MLB May transit through light surface ice to reach open water, but not to exceed 1,000 RPMs

Question 39

Max wind limitation of the 47 MLB?

Answer 39

50 Knots of Sustained Wind

Question 40

Towing limits

Answer 40

50 Displacement tons with the 2 1/4”

150 Displacement tons with the 3 1/4”

200 Displacement tons with permission from the operational commander

Question 41

How long does it take for the 47 MLB to self right?

Answer 41

8-12 seconds

Question 42

Dorade vent location

Answer 42

Port side overhead

Frames 14/15

Question 43

Anchor characteristics

Answer 43

19 Lb fortress anchor
With 9’ of 3/8” SS Chain
Attached to 300’ 2 1/4” DBN

Question 44

Tow bitt frame location

And height of tow bitt

Answer 44

Just aft of frame 2

30” high