Two new dive support vessels (DSV) operated by Belov Engenharia Ltda. have completed class commissioning and are currently performing client acceptance testing for Petrobras.
Built at Belov's own fabrication facility in Salvador, the newbuilds Belov Amaralina and Belov Humaitá are of Robert Allan Ltd.'s RAlly 4000’s Class design, fitted with Dynamic Positioning System (DP2), four diesel generators, three water jet propulsors and triple bow thrusters for redundancy. The propulsion system is diesel-electric to improve efficiency when operating in lower power DP modes. The vessel is certified as a Special Diving Support vessel suitable for Unrestricted Navigation by RINA.
The RAlly 4000 was designed to be fitted with an remotely operated underwater vehicle (ROV) launch and recovery system (LARS), an aft mounted A-frame to operate the diving bell, a decompression chamber to support the divers, and more spacious crew quarters. All of this is incorporated within a gross tonnage under 500 GRT.
Waterjets are used to ensure diver safety. Because waterjets are typically used on higher speed vessels, extensive self-propelled CFD analysis (including waterjet tunnel flow) was performed in-house by Robert Allan Ltd. to verify resistance and thrust at the slower speeds that this design will operate at when on station. The new RAlly 4000 SDSV has the following particulars:
Length overall: 40.5 m
Beam: 10.98 m
Speed: 12+ knots
Crew: 38 (including divers)