USCG COXSWAIN ACTUAL EXAMS SCRIPT QUESTIONS AND
ANSWERS FIRM A+
✔✔Bank Cushion and Bank Suction - ✔✔In extremely narrow channels, a vessel
moving through the water will cause the "wedge" of
water between the bow and the nearer bank to build up higher than on the other side.
This
bank cushion tends to push the bow away from the edge of the channel.
As the stern moves along, screw suction and the movement of water to "fill-in" where
the
boat was creates bank suction. This causes the stern to move towards the bank. The
combined effect of momentary bank cushion and bank suction may cause a sudden
shear
toward the opposite bank.
✔✔Maneuvering in Rivers-Hug the Point Maneuver - ✔✔The operator makes a small
turn toward the near bank to steer a straight course. As the channel begins to bend and
the boat moves from the bank, less of a turn will be necessary. This condition is a signal
that it is time to begin a full turn
✔✔Maneuvering in Rivers- Stay in the Bend Maneuver - ✔✔Staying in the bend is a
turn in the bend away from the point that takes precise timing. If done too late, the boat
may ground on the bank in the bend. If done too soon, there is extreme danger that a
strong and sudden sheer will occur. The bank suction on one quarter combines with the
current on the other quarter to give the boat the sheer.
✔✔Surf - ✔✔Several waves or swell breaking on the shore, shoal, reef, bar, or inlet.
✔✔Effect of Wind on Waves - ✔✔As wind speed increases, wave height will increase.
Wind can cause waves to break if blowing in the opposite direction of waves. The
Beaufort Wind Scale numbers define a particular state of wind and wave. The scale
allows mariners to estimate the wind speed based on the sea state.
✔✔Determining Wave Height Using Height of Eye - ✔✔While Boat is in the trough and
on level keel, any wave that obscures the horizon is greater than the height of the
persons eye, can be compared to deck structures.
✔✔Determine Wave Height Using Floating Structures - ✔✔If the freeboard of a buoy is
known to be 13 feet, that information can be used to determine the height of the waves
passing it. A buoy can also be used to determine the wave period. One can observe a
vessel underway and by estimating the freeboard of the vessel and observing its
motions on the water, he or she can gain a fair estimate of the seas in which it is
operating
, ✔✔Determine Wave Height Using Fixed Structures - ✔✔Observation of waves as they
pass a known fixed structure can give an accurate height as well as the wave period
✔✔Determine Wave Height Using Depth Sounder - ✔✔Using a digital depth sounder
with a fast update speed can be very accurate for determining wave height. By
comparing the depth in the trough on even keel with the depth at the crest on even keel,
an accurate measurement can be obtained.
✔✔Types of Breaking Waves- Plunging - ✔✔Plunging breakers are created when a
wave encounters a sudden decrease in depth, such as a reef or a steep rise of the
ocean floor. The momentum caused by the breaking top of the wave will cause the
water to curl
✔✔Types of Breaking Waves- Spilling - ✔✔Spilling breakers are created when wave
energy encounters a gentle sloping ocean floor. The spilling breakers normally have a
crest of white water spreading down the wave face
✔✔Types of Breaking Waves- Surging - ✔✔Surging breakers are created on very steep
beaches. The wave builds very quickly and expends its energy on the beach.
✔✔Wave Parts- Window - ✔✔A window is an area where the waves have momentarily
stopped breaking. Windows often form in the area of aerated water where a large set of
waves has just finished breaking.
✔✔Wave Parts- Saddle - ✔✔The "saddle" is the lowest part of a wave, bordered on
both sides by higher ones.
✔✔Wave Parts- High Side/ Low Side - ✔✔The "high side" is defined as the section of a
wave which carries the most potential energy. The "low side" is where the least potential
energy exists and represents the safest direction to turn when facing the wave/swell
✔✔Wave Parts- Close Out - ✔✔Closeouts occur when a wave breaks from the ends
toward the middle,
or two waves break towards each other. The middle may look like a good saddle, but
can quickly turn into whitewater. Closeouts should be
avoided because they can create more energy than a single break.
✔✔Four primary geographic divisions of SAR - ✔✔1) Maritime Pacific
2) Maritime Atlantic
3) Aeronautical Pacific
4) Aeronautical Atlantic
ANSWERS FIRM A+
✔✔Bank Cushion and Bank Suction - ✔✔In extremely narrow channels, a vessel
moving through the water will cause the "wedge" of
water between the bow and the nearer bank to build up higher than on the other side.
This
bank cushion tends to push the bow away from the edge of the channel.
As the stern moves along, screw suction and the movement of water to "fill-in" where
the
boat was creates bank suction. This causes the stern to move towards the bank. The
combined effect of momentary bank cushion and bank suction may cause a sudden
shear
toward the opposite bank.
✔✔Maneuvering in Rivers-Hug the Point Maneuver - ✔✔The operator makes a small
turn toward the near bank to steer a straight course. As the channel begins to bend and
the boat moves from the bank, less of a turn will be necessary. This condition is a signal
that it is time to begin a full turn
✔✔Maneuvering in Rivers- Stay in the Bend Maneuver - ✔✔Staying in the bend is a
turn in the bend away from the point that takes precise timing. If done too late, the boat
may ground on the bank in the bend. If done too soon, there is extreme danger that a
strong and sudden sheer will occur. The bank suction on one quarter combines with the
current on the other quarter to give the boat the sheer.
✔✔Surf - ✔✔Several waves or swell breaking on the shore, shoal, reef, bar, or inlet.
✔✔Effect of Wind on Waves - ✔✔As wind speed increases, wave height will increase.
Wind can cause waves to break if blowing in the opposite direction of waves. The
Beaufort Wind Scale numbers define a particular state of wind and wave. The scale
allows mariners to estimate the wind speed based on the sea state.
✔✔Determining Wave Height Using Height of Eye - ✔✔While Boat is in the trough and
on level keel, any wave that obscures the horizon is greater than the height of the
persons eye, can be compared to deck structures.
✔✔Determine Wave Height Using Floating Structures - ✔✔If the freeboard of a buoy is
known to be 13 feet, that information can be used to determine the height of the waves
passing it. A buoy can also be used to determine the wave period. One can observe a
vessel underway and by estimating the freeboard of the vessel and observing its
motions on the water, he or she can gain a fair estimate of the seas in which it is
operating
, ✔✔Determine Wave Height Using Fixed Structures - ✔✔Observation of waves as they
pass a known fixed structure can give an accurate height as well as the wave period
✔✔Determine Wave Height Using Depth Sounder - ✔✔Using a digital depth sounder
with a fast update speed can be very accurate for determining wave height. By
comparing the depth in the trough on even keel with the depth at the crest on even keel,
an accurate measurement can be obtained.
✔✔Types of Breaking Waves- Plunging - ✔✔Plunging breakers are created when a
wave encounters a sudden decrease in depth, such as a reef or a steep rise of the
ocean floor. The momentum caused by the breaking top of the wave will cause the
water to curl
✔✔Types of Breaking Waves- Spilling - ✔✔Spilling breakers are created when wave
energy encounters a gentle sloping ocean floor. The spilling breakers normally have a
crest of white water spreading down the wave face
✔✔Types of Breaking Waves- Surging - ✔✔Surging breakers are created on very steep
beaches. The wave builds very quickly and expends its energy on the beach.
✔✔Wave Parts- Window - ✔✔A window is an area where the waves have momentarily
stopped breaking. Windows often form in the area of aerated water where a large set of
waves has just finished breaking.
✔✔Wave Parts- Saddle - ✔✔The "saddle" is the lowest part of a wave, bordered on
both sides by higher ones.
✔✔Wave Parts- High Side/ Low Side - ✔✔The "high side" is defined as the section of a
wave which carries the most potential energy. The "low side" is where the least potential
energy exists and represents the safest direction to turn when facing the wave/swell
✔✔Wave Parts- Close Out - ✔✔Closeouts occur when a wave breaks from the ends
toward the middle,
or two waves break towards each other. The middle may look like a good saddle, but
can quickly turn into whitewater. Closeouts should be
avoided because they can create more energy than a single break.
✔✔Four primary geographic divisions of SAR - ✔✔1) Maritime Pacific
2) Maritime Atlantic
3) Aeronautical Pacific
4) Aeronautical Atlantic
