Navy: Calibration flaw crashed Yorktown LAN
Connecting state and local government leaders
PASCAGOULA, Miss.—Human error, not Microsoft Windows NT, was the cause of a LAN failure aboard the Aegis cruiser USS Yorktown that left the Smart Ship dead in the water for nearly three hours last fall during maneuvers near Cape Charles, Va., Navy officials said. The Yorktown last September suffered an engineering LAN casualty when a petty officer calibrating a fuel valve entered a zero into a shipboard database, officials said. The resulting database
PASCAGOULA, Miss.Human error, not Microsoft Windows NT, was the cause of a LAN
failure aboard the Aegis cruiser USS Yorktown that left the Smart Ship dead in the water
for nearly three hours last fall during maneuvers near Cape Charles, Va., Navy officials
said.
The Yorktown last September suffered an engineering LAN casualty when a petty officer
calibrating a fuel valve entered a zero into a shipboard database, officials said. The
resulting database overload caused the ships LAN, including 27 dual 200-MHz Pentium
Pro miniature remote terminal units, to crash, they said.
The petty officer, who has since left the Navy, fed the bad data into the Remote Data
Base Manager, a Standard Monitoring Control System application. SMCS, developed by
Canadian Aviation Electronics Inc. of Toronto, allows sailors to monitor the ships
engineering and propulsion plant for potential casualties.
The system provides troubleshooting data and normally indicates whether a valve is open
or closed without requiring calibration. But something went wrong.
There was a problem in that this one valve was closed, but SMCS wasnt
indicating it as such, said Cmdr. Eric Sweigard, the Yorktowns commanding
officer. So this petty officer started playing with the data.
This was the only time it occurred, and since then there have been some changes
made to prevent it from happening again, he said.
SMCS managers are now aware of the problem of entering zero into database fields and
are trained to bypass a bad data field and change the value if such a problem were to
occur again, Sweigard said.
Now that we know what can happen, weve realized how to bring the system
back quickly, Petty Officer 1st Class Phillip Cramer said. All we have to do
is change the zero to any number, and everything comes right back up.
The Yorktown was not towed into port as a result of this incident, Sweigard said. The
ship restored the LAN in about two hours as it made its way to the Naval base at Norfolk,
Va., under its own power, he said.
Its not something that we desire, but ships do go dead in the water,
Sweigard said. People sometimes make mistakes and systems break. The trick is we
have trained our crew to react to those situations.
The Office of the Navys Chief Information Officer is conducting a detailed
inquiry of the Yorktown incident, Navy officials said. A report from the Navy CIO is
expected later this month, officials said.
Regardless of who or what was at fault for the Yorktown LAN failure, the stakes for the
Navy are high. The service plans to install Smart Ship technology on all its cruisers.
The Navy selected NT 4.0 as the standard operating system aboard the Yorktown for its
reliability, functionality, low cost and ease of integration, said Lt. Danny Bethel,
Yorktowns electronics material officer. NT runs the Yorktowns integrated
bridge, engineering, condition assessment and damage control systems.
The Yorktown uses dual 200-MHz Pentium Pro systems from Intergraph Corp. of Huntsville,
Ala., to run NT over a fiber-optic, asynchronous transfer mode LAN. Shipboard users can
access computers from 15 locations so that the Yorktown can be driven from virtually
anywhere on the ship.
The Navy has reduced the Yorktowns crew from about 350 sailors to 307 personnel
by adopting new policies and procedures, as well as through the use of commercial
products, Sweigard said.
The Navys Western Hemisphere Group will begin installing Smart Ship technologies
aboard the USS Ticonderoga and USS Thomas S. Gates early next year, said Lt. Danny
Hernandez, public affairs officer for the group in Mayport, Fla.
Smart Ship was the brainchild of Adm. Jeremy Boorda, the late chief of Naval operations
who wanted to save money by reducing personnel aboard Navy ships while maintaining
safety.