Versatile RAmpage 5500-ZH Diesel-Hybrid Delivered To Seaways International

September 21, 2016

The Seaways 24 is the latest addition to the RAmpage 5500-ZH class of Infield Support Vessel designed by Robert Allan Ltd. and constructed at Keppel Singmarine. The Owner, Seaways International took delivery of the versatile and adaptable vessel on August 15, 2016.

The vessel was designed and constructed to ABS requirements with the following Class Notation:

✠ A1, Offshore Support Vessel (AH, TOW, SUPPLY-HNLS, FFV1 + FFV 2, OSR-S1)
✠ DPS-2, ✠ AMS, ✠ ACCU, UWILD, Green Passport, ENVIRO+, SSR-GR B (300), BP125, BWT+, NBLES, CRC

Seaways 24 is a multi-function vessel with the following capabilities:

  • Tanker handling and berthing (push-pull mode)
  • SBM “holdback” duties
  • Buoy maintenance
  • Anchor handling
  • Floating hose handling
  • Deck cargo carriage and transfers including open sea operations with installed offshore crane
  • Liquid cargo transfers including methanol
  • Fire-fighting with powerful Fi-Fi system with total pump capacity up to 8,200 m3/hour
  • ROV support operations
  • Oil recovery Standby Class 1 for recovery and storage of hydrocarbons with flashpoint below 60 °C
  • Oil spill response with dispersant system and onboard Lamor oil spill collection system
  • Ocean towing
  • Standby and rescue operations with helicopter winch area, deck rescue zone, hospital, morgue, two fast rescue boats, and with facilities sufficient to accommodate 300 survivors


Particulars of the Seaways 24 are as follows:

  • Length overall: 55.00 metres
  • Beam, moulded: 15.00 metres
  • Depth, moulded (hull): 7.33 metres
  • Maximum draft: 6.05 metres

Tank capacities are as follows:

  • Fuel oil: 590 m3
  • Potable water: 119 m3
  • Drill water: 338 m3
  • Water ballast: 503 m3
  • Methanol cargo: 99 m3
  • Recovered oil: 263 m3
  • Main engine lube oil: 20 m3
  • Z-drive lube oil: 6 m3
  • Hydraulic oil: 7 m3
  • Sludge tank: 11 m3
  • Grey water: 18 m3
  • Sewage holding tank: 18 m3
  • Oil dispersant: 25 m3
  • Foam: 36 m3

On trials, Seaways 24 met or exceeded all performance expectations, with the following results:

  • Bollard pull, ahead: 125 tonnes
  • Bollard pull, astern: 107 tonnes
  • Free running speed, ahead, hybrid mode: 15 knots
  • Free running speed, ahead, electric mode: 7 knots

The Powering and Propulsion system features:

  • 2 x 3,000 kW MAK 9M25 main engines
  • 2 x CAT MTA8 Z-drives each with two Power Take In (PTI) shaft connections turning CPP propellers of 3.4 m diameter in nozzles
  • 2 x 560 kW PTI propulsion booster/economical speed/DP operation electric motors
  • 2 x main engine Power Take Off (PTO) gearboxes with 2 x Fi-Fi pumps and 2 x 1,200 ekW constant speed shaft alternators
  • 2 X 830 ekW C32 and 1 x 350 ekW C18 ship’s service gensets

This configuration allows the following operating modes:

  • Diesel-Mechanical mode on main engines with house electrical power supplied by shaft alternators or service gensets
  • Diesel-Electrical mode for economical operations on propulsion electrical motors only and with house and propulsion loads on ship’s service gensets
  • Hybrid mode for maximum bollard pull and speed on main engines and on propulsion electrical motors with electrical power supplied by service gensets
  • DP2 mode on main engines with house electrical power supplied by shaft alternators or service gensets
  • DP1 mode on propulsion electrical motors and with house and propulsion loads on ship’s service gensets
  • DP1 mode on one main engine only with house electrical power supplied by shaft alternator or service genset
  • Fi-Fi 2 operation on main engines only

Robert Allan Ltd. designed the vessel to current standards for improved emissions and environmental protection, and outfitted it to the highest standards to accommodate complement of 34. Master’s, Chief Engineer’s and two single officer’s cabins are located on the upper “A” deck, with an additional private officer’s cabins located on the Forecastle deck and Main deck. Additionally, four double crew’s cabins and three four-man cabins are arranged on the Forecastle deck. On Main deck there are two more four-man cabins and one single man cabin. Also, on Main deck are a galley, lounge/mess, ship’s office and recovery area with twenty berths. The lower deck below contains the galley’s stores, cooler and freezer rooms, and laundry room.


The deck machinery comprises a double drum towing winch with roller fairlead on at the bow, and a double drum waterfall type anchor handling/towing winch on the aft deck. Two large spare towing line reels are located in the hold. In addition, a towing hook, tow pin/shark jaw set, two capstans, gob-eye, stern quarter pins and two tugger winches are installed on the aft deck to facilitate anchor and line handling operations. A third tugger winch is located on the forecastle deck for convenient connection of the floating pipes to the FPSO pipe flushing connection. Dirty oil is diverted to a full width hose sump in the cargo deck.

The vessel is equipped with stern roller, 5.5 m long and 2 m in diameter. A jib arm is arranged on starboard to handle inflatable boom deployment during oil recovery operations, and scramble nets are arranged port and starboard to assist the recovery operations. Installed on the aft working deck is the powerful offshore rated Palfinger crane, with a 25 t SWL and outreach up to 25 m.

The vessel carries two FRB 650 Fast Rescue Boats and one Wave Handler 800 catamaran type work boat.

The wheelhouse provides maximum all-round visibility with forward and aft control stations giving maximum visibility to both fore and aft deck-working areas.

Ship-handling fenders at the bow consist of one row of 900 x 500 cylindrical fender at the main deck level, with 450 mm “W” fenders between the main deck and the knuckle. A lower system of 900 x 400 push fenders is arranged above the waterline at the bow. A 500 x 500 hollow “D” fender provides protection at the main and fo’c’sle deck sheer lines, and 300 mm “W” block type fendering is used at the stern.

For more information on the Seaways 24 or any of the RAmpage series tugs, or on any other vessel designs developed by Robert Allan Ltd., please contact us at

SI-55 30000R22 General Arrangement.cdr