Belov to Build and Operate Robert Allan Ltd. Designed Dive Support Vessels for Petrobras

November 19, 2018

A renewed wave of investments in the Brazilian offshore industry has appeared on the horizon kindling the demand for new highly specialized vessels such as a new Robert Allan Ltd. design of the RAlly family. Underwater service providers play a major role in maintaining offshore assets, especially in deep water, by  performing diving operations and ROV surveys (Remotely Operated Vehicles). In the plethora of Brazilian operators, a company stands out from the crowd, having performed work for the Brazilian state-run oil company Petrobras for several years: Belov Engenharia Ltda.

Understanding this new demand, and preparing for the tenders to come, Belov has decided to build (at their own fabrication facility in Salvador) and operate two new Dive Support Vessel (DSV), engaging Robert Allan Ltd. to prepare the Contract Design package of the vessel. These interesting new vessels to be named Belov Humaitá and Belov Amaralina will be RAlly 4000’s, fitted with a Dynamic Positioning System (DP2), diesel electric propulsion plant driving water jet propulsors and bow thrusters. The vessel is to be certified as a Special Diving Support Vessel suitable for Unrestricted Navigation, classed by RINA.

The RAlly 4000 is being designed by Robert Allan Ltd. to be fitted with an ROV LARS (Launch and Recovery System), 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 will be 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 was performed in-house by Robert Allan Ltd. to verify resistance and thrust at the slower speeds that this design will operate at.

Belov Humaitá and Belov Amaralina have the following particulars:

  • Length overall: 41.00 m
  • Beam: 10.75 m
  • Speed: 12 knots
  • Crew: 38 (including divers)

For more information on the RAlly series or any other tug design series, please contact