Introduction to Dynamic Positioning

In its most basic form the DP system is a control system that measures environmental inputs then sends commands to the thrusters to counter these forces to keep the vessel stationary, or to move it along a specified track. The type of task the vessel performs will determine which Class of system is used.

Another eco-ferry to set sail in San Francisco

Pisces is the second of two 25 knot, 149-passenger vessels recently built by WETA. The City of Alameda manages the Harbor Bay ferry service and contracts with Harbor Bay Maritime to operate the service. The City of Alameda chartered the WETA-owned ferry for use on the Harbor Bay Ferry service.

Like its sister vessel, Gemini, which set sail on the Tiburon-San Francisco commute in December 2008, Pisces is the nation’s most environmentally friendly ferryboat. Its exhaust is 85% cleaner than EPA emissions standards for Tier II (2007) marine engines and is ten times cleaner than existing Bay Area ferries. Pisces also incorporates innovative measures to protect bay and marine life, including low-wake, low-wash hulls.

Urea coming to an engine room near you?

Urea…yes…a primary waste product of urine is actually a key ingredient to reducing nitrogen oxides or NOx emissions from diesel engines. NOx is a by-product of combustion, and is the primary cause of smog, acid rain, and the production of ozone. Not only does NOx not take too kindly to the atmosphere, it also does not take kindly to humans. NOx and various toxic by-products from reactions with NOx cause lung irritation, and in high enough concentrations permanent lung damage and biological mutations.