BM3 Ops And Seamanship Flashcards
What is displacement?
The weight of the vessel measured in long tons. *long ton is 2,240 pounds
What is critical speed?
The max speed a displacement hull will travel before requiring excessive power. 1.34x the square root of the waterline.
What is light displacement?
Weight excluding fuel, water, outfit cargo, crew and passengers.
What is loaded displacement?
Fuel, water, outfit cargo, Crew and passengers
What is dead weight?
The difference between light and maximum loaded displacement.
What are lines measured by?
Circumference
What is wire rope measured by?
Diameter
What is right hand lay known as?
Z
What is left hand lay known as?
S
What is Manila line made from?
Abaca plant
What is marlin line made from?
Hemp. * does not recover from being stretched.
What is the main component in natural fiber line?
Cellulose
During bending, line strength may decrease up to __ times.
5
Damage to internal natural fiber lines occurs when a line is under strain greater than ____% of it’s breaking strength
75%
Cockles can reduce the strength of a line by as much as ___.
1/3
If the circumference of a line is reduced by ___% or more, the line should be replaced.
5%
Rust that extends into the cross section of a line can lower the strength by as much as ___%.
40%
A knot can reduce the strength of a line by as much as ___-___%.
50-60%
A splice can reduce the strength of a line by as much as ___-___%.
5-10%
The eye of a line should be __ times the diameter of the line.
6
For three strand line how many tucks are required for natural line?
3
For three strand line, the number of tucks for synthetic line is__.
4
Markings for splicing line:
R- length of fid
X- desired loop size (where the core will come out)
Z- 1/2 fid from X towards the slip knot
Slip knot is 5 fid lengths towards the standing line.
How many wraps including an extra foot are needed for temporary whipping?
15-20