MAYPORT Florida —
MAYPORT Florida. -- The
Dive Locker at Southeast Regional Maintenance Center in Mayport accomplished a
first-ever waterborne repair on one of USS NEW YORK’s (LPD 21) propeller blades,
enabling the ship to deploy on time with the IWO JIMA Amphibious Ready Group
During a routine underwater hull
cleaning in mid-November, one blade attachment bolt was found to be backed
out. The bolt is one of 80 bolts that attaches
controllable-pitch propeller blades to the main propeller hub. The 10-inch, 30-pound bolt was dangerously
close to falling off.
Chief Warrant Officer 2 Sean Bryans,
Diving Officer at SERMC, said maintenance teams from SERMC and Naval Sea
Systems Command rushed to develop procedures to replace the bolt without
pulling the ship out of the water.
Propeller blades are routinely removed from the hub while the ship is in
the water for other ship classes, but never before on a SAN ANTONIO class LPD
In addition to replacing the
loose bolt, all eight bolts that hold that blade to the propeller hub were removed
and replaced to conform to strict engineering specifications and to ensure the
ship would be ready for the high tempo of a full deployment. In fact, all 80 bolts on both propellers were
inspected to ensure proper condition and torque. Any bolts not meeting
standards were replaced.
“We tested the bolts in our
Non-Destructive Testing lab,” said Navy Diver First Class Edward Briggs, SERMC’s
diving supervisor. “The ones that failed
had to be replaced.”
Briggs said the bolts are torqued
using specialized hydraulic tools that “stretch” the bolts as they are
tightened and the stretch must fall within specs as well as torque. These tools did not exist to perform a
waterborne repair prior to this effort.
“Working with the shipbuilders,
SERMC fabricated some new sockets and tools so we could work underwater and get
accurate measurements on torqueing,” said Senior Chief Navy Diver Ashley
Gossett, SERMC’s master diver.
Gossett said that with NEW YORK’s
departure date looming only a few weeks away, a dry dock repair was never a
consideration. The cost in time and
money prohibited such an evolution.
The cost to dry dock a ship can
approach more than $1 million and takes several weeks to execute.
SERMC’s Dive Locker worked for seven
days and totaled more than 600 man hours, including 21 hours in the water .
“The Dive Locker has supported the
ARG since their arrival last summer,” Bryans said of the three-ship homeport change. “This should give the other ships here the
confidence that we can handle any job.”
- SERMC -