A new RAstar 3200 from Robert Allan Ltd. for SAAM S.A.

October 16, 2015

The Arriero is the latest addition to the RAstar 3200 Series of terminal support tug designs by Robert Allan Ltd., delivered to its owner: SAAM S.A. on September 20th, 2015. Constructed at Guangdong Bonny Fair Heavy Industry Limited in China, the Arriero will operate in Montevideo, Uruguay and is the first in a series of four (4) RAstar 3200 tugs under construction for this owner. In South America an “arriero” is a country man who transports coffee, maize, cork, wheat, and myriad other goods using pack animals. While the tug Arriero will not be transporting these goods directly, it will ensure the safe passage and berthing of those vessels which transport vital goods in and out of South America.

Particulars of the Arriero are as follows:

Length overall:
Beam, moulded, extreme:
Depth, moulded (hull):
Maximum draft:
– 32.0 m
– 12.8 m
– 5.5 m
– 5.78 m (to bottom of skeg)


The tug was designed and constructed to ABS requirements with the following notation:

Notation: ✠ A1, Ⓔ, ✠ AMS, Towing Vessel (Escort Vessel), Fire Fighting Vessel Class 1, Unrestricted Navigation

Major tank capacities are as follows:

Fuel Oil:
Potable Water:
Sewage Holding Tank:
– 215 m³
– 42 m³
– 9.0 m³
– 2.8 m³


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

Bollard Pull, ahead:
Bollard Pull, astern:
Free running speed, ahead:
– 85 tonnes
– 84 tonnes
– 13.8 knots


The vessel has been outfitted for a normal operating crew of twelve. The Master’s and Chief Engineer’s cabins are located on the main deck, with five additional double crew cabins located on the lower accommodation deck.

The deck machinery comprises a ship assist hawser winch on the bow, and a towing winch on the aft deck, with capacities of 150 m of 80 mm synthetic line, and 700 m of 54 mm SWR, respectively.

The wheelhouse is designed for maximum all-round visibility with a forward control station providing maximum visibility to both fore and aft deck working areas.

Four Boats

Main propulsion for each tug comprises a pair of GE 8L250 diesel engines, each rated 2440 kW at 1050 rpm, and each driving a Rolls- Royce, US 255 fixed pitch Z-drive unit, in ASD configuration.

The electrical plant comprises two (2) identical ship service gensets, each with a power output of 136 ekW, and one (1) harbour genset, with a power output of 51 ekW.

Ship-handling fenders at the bow consist of two rows of 900 x 450 cylindrical fender at the main deck lever. Two rows of DN150 steel fenders, with aircraft tires, provides protection at the main and foc’sle deck sheer lines, and 400 mm “W” block type fendering is used at the stern.

The RAstar offshore/escort tug designation is reserved for a unique series of ASD tugs, designed with a sponsoned hull form, which has been proven in both model and full-scale testing to provide significantly enhanced escort towing and seakeeping performance. Motions and accelerations are less than half those of comparable sized “standard” tug hulls. This class of tug was selected by the Client in order to best cope with the sea conditions existing outside the main harbour entry, and to provide an enhanced escort capability keeping pace with the demands of the growing port.

For more information on the Arriero or any of the RAstar Series tugs, or on any other vessel designs from Robert Allan Ltd., please contact us at design@ral.ca.