Perform as a Member of a Hull Inspection Team

052-238-1650

By: SGT GARCIA

Table of Contents

• References• Task, Conditions, and Standards• Types of Inspections• Cleaning and Inspection Tools• Major Components• Performance Steps

References

• FM 20-11: Military Diving• NAVSEA S0600-AA-PRO-010, NAVSEA S0600-

AA-PRO-160, NAVSEA S0600-AA-PRO-170: Underwater Ship Husbandry Manuals

• NSTM S9086-CQ-STM-010: Waterborne Underwater Hull Cleaning of Navy Ships

Task, Conditions, and Standards

• Task: Perform as a Member of a Hull Inspection Team (052-238-1650)

• Conditions: As a diver in a field environment, you are given orders to conduct a hull inspection, the appropriate diving equipment, an underwater photographic and video set, and an underwater construction tool kit.

• Standards: Perform as a member of a hull inspection team, noting all variations from the ship drawings and utilizing underwater camera systems and measurement devices.

Types of Inspections

• Level 1 inspections are visual inspections documented in writing and recorded on diver hull inspection data forms (NAVSEA 4730). Supplement documentation such as color photographs and/or color video should be used to depict the condition of the hull and appendages.

• Level 2 inspections are system specific inspections which require detailed measurements and assessment of the system be recorded on the appropriate diver hull inspection forms. Additional sketches should be provided which clearly document the extent of damage and color photographs and/or color video should be used to record the condition of the system.

Cleaning and Inspection Tools

• Putty Knife • Wire Brush • Brush• Hull Scrubber• Green scratch pads • Pressure Washer • Calipers• Machinist Ruler• Camera

Major Components

Bow Thruster •On all Boats, your going to need to inspect both sides for damage and over growth

•Look at the fins and propeller (screw) for bent or broken pieces

•Check to make sure the propeller is free of any debris i.e. rope and large growth.

Major Components

Keel Cooler•The keel coolers are underwater radiators for the ships engines. •These need to be inspected thoroughly to make sure there are no signs of damage that could cause a leak •They need to be cleaned and cleared of all debris and growth

Major Components

•The rudders and rear propellers need to be inspected for damage

•Thoroughly inspect each propeller fin for major damage. i.e. “dog eared” •Look for tangled rope in the joint areas and make sure all moving pieces have free operation.

Rudders and screws

Major Components Sea Chest

•Size, shape and location may change on all the different models of boats but they all have the same operations, to allow a large amount of water to flow in to the ships ballast, also it helps cool the engines

•Make sure the grate is free and clear of debris and overgrowth, check to make sure the bolts are all there.

Major Components

•The drive shaft is a long cylindrical shaft that transfers power from the engine to the propeller

•This should be kept clean of growth.

•Fishing line and net has a tendency to get wrapped around it and work its way intothe packing areas

- Packing area -

Drive Shaft

Major Components

Can you count how many anodes are in this picture? In 10 sec? 19

•Anodes can come in all shapes and sizes •Be sure to check all anodes for corrosion

•Give an estimated percentage of the remaining anode

Zinc Anodes

Performance Steps

1. Assemble the diving equipmenta. Verify the camera system has adequate available

memory and battery lifeb. Review the diagrams of the ship and the previous

hull inspection formc. Ensure that measuring devices are available, such

as a machinist ruler and calipers

Performance Steps

2. Conduct a Level 1 or Level 2 inspectiona. Annotate the measurementsNote: Measurements should be annotated according to

NAVSEA S0060-AA-PRO-170, Table 17-3.1b. Apply common terms associated with any common

damageNote: Terms of damage should be applied according to

NAVSEA S0600-AA-PRO-10c. Record the condition of the hull

Table 17-3.1, Measurement Tolerances

Terms of Damage

a. Crack. A linear rupture of material under stress. Cracks may form anywhere on asurface, but are usually found near an edge or joint. Cracks have depth, length, andwidth and are not simply a surface defect.

b. Dent. A hollow area made by a blow or collision. There is no loss of material with a dent.

c. Gouge. A scooped out, shallow area or groove in the material caused by contact orcollision with a hard object. This is common on softer material such as sonar domerubber windows and shaft coatings, but may also be found on hull plating.

d. Scratch. A narrow surface defect that can be felt, but which has no depth into thematerial. Typically, scratches can be buffed out.

Terms of Damage

e. Surface indication. Any inconsistency of the surface that looks like a scratch or “hair line crack” but cannot be felt or buffed out.

f. Tear. Pulled apart or separated by force, common on the leading edge of a bilge keel or a sonar dome rubber window.

g. Delamination. Separation between layers, common on shaft coatings and sonar domes. Delaminations may be obvious with entire sections of material lost or may be hidden as a subsurface failure. Subsurface delaminations may appear as bulges.

h. Discontinuity. Any imperfection (e.g., surface indication or crack) in the material that has been confirmed with an approved non-destructive test procedure using qualified personnel.

Performance Steps

3. Identify objects not on the diagram of the ship, such as mines.

a. Search for mines.1) Ensure that you do not expose any mines to movement, light, or high magnetic

signatures because they can be detonated in a variety of ways.2) Use extreme caution when searching, and do not touch or move any mines.

b. Mark the location of a mine.1) Use a grease pencil , and mark the depth of the mine on the hull above the water

line with an arrow pointing towards the location of the mine.2) Record the approximate height, width, and depth of a mine and any words,

symbols of color markings

Performance Steps

4. Use the running log, photographs, video, and diver’s notes to fill out the hull inspection forms after completing the dive.

Questions?