Robert Allan Ltd. designed ART 80-32 Rotortugs® delivered in Hong Kong and ready for deployment to Western Australia

December 9, 2014

RT Endeavour and RT Discovery in Hong Kong ready for deployment to Western Australia


The RT Discovery and RT Endeavour, ART 80-32 Class Rotortugs®, have been delivered by Cheoy Lee Shipyards to Owner’s Elisabeth Ltd. The vessels are currently in Hong Kong and are ready for deployment to a busy commodity Port in Western Australia. These two vessels represent the first half of Elisabeth Ltd’s four boat order with Cheoy Lee Shipyards.

The Advanced Rotortug® (ART) designs incorporate the patented triple Z-Drive Rotortug®, concept, featuring enhanced omni-directional manoeuvrability, and the benefits of a fully redundant and precise propulsion machinery configuration.

The Owner as well as Rotortug B.V. provided significant input into the requirements for this design, and Robert Allan Ltd. developed a unique, customized design optimized for their operations.


RT Endeavour free sailing


The ART 80-32 has an installed power of 3 x 1765kW, delivering well over 80 tonnes of bollard pull in both ahead and astern directions. The hull form has been developed from Robert Allan Ltd.’s high performance escort tugs and has been adapted to suit the Rotortug® concept, providing enhanced stability, sea-keeping and escort performance. The design process involved a detailed CFD study of different hull forms to determine the preferred hull characteristics.


ART 80-32 hull in CFD side stepping test at 6 knots


Particulars of the new design are as follows:

Depth (Least Moulded):
Extreme Draft 215 DWT:
Extreme Draft 75 DWT:
– 31.95 m
– 12.60 m
– 4.82 m
– 6.31 m
– 5.91 m
– 491



  • Fuel oil capacity: 200 m³
  • Fresh water capacity: 32.8 m³



  • Three Main Engines CAT 3512C HD rated 1765 kW @ 1800 RPM (“C” rated, IMO Tier II Compliant)
  • 3 x Schottel SRP 3000 Z-drives (2 forward, 1 aft) with 2.3 m fixed pitch propellers driven through MCD 3000 LD slipping clutches
  • 2 x CAT C6.6 genset (143 ekW @ 1500 RPM) and 1 x CAT C4.4 genset (51.5 ekW @ 1500 RPM)
  • Kraaijeveld Safe Winch Forward electric towing winch and anchor windlass
  • Kraaijeveld Safe Winch Aft electric towing winch
  • FIFI 1 equipment includes a single 2850 m³/hr pump driven off the Port main engine, 2 x 1200 m³/hr monitors, water spray, as well as foam system capability of 300 m³/hr from the staboard monitor.


Ship-handling fenders at the bow comprise an upper row of 800 mm diameter cylindrical fender and a lower course of W-fender. Sheer fenders consist of lightweight Polymarine foam type fender, 300 mm x 300 mm.

The tug was constructed to LR Class requirements with the following notation:

LLOYD’S ✠ 100A1 TUG, ✠ LMC, UMS, IWS, Fire-Fighting Ship 1 (with water spray)

On trials, the RT Discovery and RT Endeavour achieved essentially equal ahead and astern speeds of over 13.5 knots and sidestepped at over 7 knots.


RT Endeavour and RT Discovery in Hong Kong awaiting deployment to Western Australia


The vessel has been outfitted to high standards for a crew of 6 people. The main deckhouse contains the entrance lobby, galley, mess, two officer cabins each with ensuite WCs, and a common WC. The lower deck contains 2 double berth cabins each with ensuites, a laundry, and galley stores.

The wheelhouse offers exceptional 360 degree views and unobstructed views of the entire fore and aft working decks from a single control station thus improving safety of crew by ensuring working areas around winches, staples, and mooring bitts are clearly visible to the operator.

Entry from the main deck to the engine room is first through the switchboard room which offers sound isolation to the main deck accommodations. Access to the engine room is then through doors leading from the switchboard room.

With the Rotortug® thruster configuration, a modern high performance hull form, exceptional 360 degree wheelhouse views, and an optimized and safe arrangement of the tug’s working areas, the RT Discovery and RT Endeavour will be valuable, high performance, workhorses in the demanding service of Western Australian.

For more information on the ART Class tugs, or any other high-performance vessel designs developed by Robert Allan Ltd., please contact