By Ryo Isobe, FLEACT Yokosuka Public Affairs
YOKOSUKA, Japan (June 14-15, 2016) – Ship Repair Facility and Japan Regional Maintenance Center’s (SRF-JRMC) diver team, called the “dive locker,” recently supported USS Fitzgerald’s (DDG 62) successful dry-docking for its docking selected restricted availability.
SRF-JRMC provides ship maintenance and modernization for Commander, Naval Forces Pacific and U.S. Pacific Fleet using advanced industrial techniques while keeping the U.S. 7th Fleet operationally ready. While dry-docking is a land-based evolution, the command’s divers play a key role in several important jobs which occur underwater.
“[Whether we use umbilical or scuba] depends on the type of work we are doing,” said Navy Diver 3rd Class Casey Ras. He said the umbilical operations, where a diver is connected to the surface by hoses securing an abundant air supply, are more comfortable since the divers do not have to worry about the time limit that a scuba tank has.
A necessary task before starting any dry-docking evolution is caisson inspection. Caissons are watertight structures which act as gates to allow movement of water into and out of the dry docks. This inspection must be done to ensure the caisson fits securely in the sill to prevent water spillage into the dry dock after it is pumped dry.
Underwater, divers visit and inspect the caisson sill, or the place where the caisson rests within the drydock. They also examine the keel and side blocks to ensure the vessel can be safely landed without damage once the water is drained from the dock.
Prior to the docking of Fitzgerald, Navy Diver 3rd Class Kadell Johnson and Master Labor Contract Diver Masaki Kanno inspected the caisson sill as part of the dry-docking evolution.
“Sometimes the water is very murky during the work,” Kanno said. “Often the debris becomes difficult to remove, and you need a lot of strength to clear it out.”
With Fitzgerald securely moored in the dock, water was pumped out for the divers to go to work and begin the diving evolution.
Chief Navy Diver Erwin Vargas and Japanese Master Labor Contract diver Kazuyuki Ishiwata verified the keel and side blocks were properly placed and ensured no damage to the hull as the ship settles on the keel and side blocks. This involves using wooden measuring tools to gauge the space between the hull and the blocks and confirming the hull was properly aligned. It took the divers about 30 minutes to check the hull from stern to bow.
“With scuba, we only have so much time down there,” Johnson said. “We are breathing hard, so we are breathing out all the air that is in the tank. We would rather have an almost unlimited air supply that’s on the surface versus only something that would last 30 minutes on our back.”
Ishiwata also explained the dangers of block inspection: “Since I have almost 10 years of experience, I am not scared anymore or get tense before diving, but [this kind of job] could be very unnerving for a person unfamiliar with diving. Since diving is inherently risky, mutual trust among divers is very important.”
“We can’t maneuver the ship into the dock without help from everyone in the team,” said Docking Officer Lt. David Reinhardt, the officer responsible for Fitzgerald’s safe and efficient dry-docking. He emphasized the process went smoothly with thanks to the team effort of all who were involved.
During the evolution, ship’s force, the divers and Reinhardt communicated via underwater communication tools to safely execute the keel and side block inspection. Masaki Fukuda, the command’s dock master, also supported the docking operation.
Other personnel from the command’s dry docks branch, carpenter shop, lifting and handling department, dock maintenance and forklift operation section and Fleet Activities Yokosuka’s port operations also coordinated to accomplish the docking evolution.