Description of Project:
This project began as a conceptual design for a bid response to Petrobras. Petrobras' goal was to phase out offshore crew transport via costly helicopters and rough riding conventional crewboats with smooth riding SWATH ships. The Petrobras bid package had many stringent requirements ranging from economics to ergonomics.
The economic requirements included a monthly average speed of 25 knots at less than 90% MCR and the prediction of the fuel consumption. The ergonomic requirements were defined to limit the incidence of seasickness to less than 5% in 4 hours exposure in the 2- to 3-meter seas so common to the Campos Basin where the vessel would operate. They also required comfortable seating, ample leg room and a HVAC system with a relatively high rate of air exchange.
ACMA was given the complete vessel design responsibility by Trico Marine. The concept design went through several major revisions in response to the final Petrobras bid package, including the propulsion plant. ACMA provided resistance and motion performance predictions over a speed range of 0-30 knots. A cost-effective design, which included implications from a builder's perspective, was the end result of the design process. Extensive model testing was carried out under the direct supervision of ACMA with Petrobras in attendance. Upon Trico's award of the contract, ACMA commenced with detailed design.
The final design presented a number of challenges, while incorporating many high tech features, such as a gas turbine coupled to controllable pitch propellers via a 27:1 reduction gear and an active fin system. ACMA was responsible for all aspects of the design, including hydrodynamics, propulsion, global and local FEA structure analysis, auxiliary systems, safety systems, purchase specifications for all major equipment, and interfacing with class and regulatory bodies (ABS & USCG). The detailed design was carried out concurrently with construction due to the short delivery schedule. ACMA participated in the construction process as the owner's representative.
This vessel has been successfully in operation offshore Brazil since January 1999. BACK |
