Cheoy Lee Shipyards has delivered the PSA Nebula, completing a 16-vessel fleet-expansion contract of Robert Allan Ltd.-designed Z-Tech 6000 tugs for PSA Marine. Equipped with Niigata propulsion and achieving a 63.6-tonne bollard pull, the highly customized, automated vessel is optimized for global harbor towage operations across Latin America and Southeast Asia.
Canada | April 6, 2026 – Highlighting a major milestone in global harbor towage logistics, Cheoy Lee Shipyards has delivered the PSA Nebula, the 16th and final harbor tug in a major multi-vessel contract for global towage operator PSA Marine.
Designed by the renowned Canadian naval architectural firm Robert Allan Ltd., the PSA Nebula is built to the advanced Z-Tech 6000 specification. The vessel has officially departed Cheoy Lee’s Hin Lee shipyard in Zhuhai, China, to join PSA Marine’s permanent fleet deployment at the Port of Singapore.
The delivery brings a successful close to a rapid, high-volume fleet expansion program that commenced less than two years ago with the delivery of the series’ first boat, the PSA Gemini, in mid-2024.
Global Footprint of the Z-Tech 6000 Series
Rather than concentrating the new tonnage in a single hub, PSA Marine has dynamically deployed these 16 new high-spec assets across its international network to handle complex ship-assist duties. The distribution underscores the localized flexibility of the Robert Allan design:
- Singapore (Hub Operations): 7 vessels (including PSA Nebula)
- Thailand (TSC Marine Joint Venture): 6 vessels
- Panama: 2 vessels
- Peru: 1 vessel
The completion of this contract cements a multi-decade relationship between the operator and the designer. To date, PSA Marine has integrated 61 Robert Allan-designed tugs into its global fleet, 32 of which utilize the proprietary, award-winning Z-Tech hull configuration.
Technical Specifications & Trial Performance
The PSA Nebula is engineered to operate in tight harbor environments while providing the stability and responsive handling necessary to assist mega-containerships and low-freeboard industrial barges.
| Parameter / Metric | Technical Specification |
| Length Overall (excl. fenders) | 30.00 meters |
| Beam, Moulded | 12.00 meters |
| Depth, Least Moulded | 5.06 meters |
| Maximum Navigational Draft | 5.20 meters |
| Main Engines | 2 x Niigata 6L28HX medium-speed (1,654 kW at 750 RPM) |
| Propulsion / Z-Drives | 2 x Niigata ZP-31B ASD units with 2.3-meter propellers |
| Bollard Pull (Trials) | 63.6 tonnes (Exceeded 60 MT baseline) |
| Top Speed (Trials) | 12.4 knots |
| Tank Capacities | Fuel Oil: 130 m3 |
Advanced Deck Machinery and Operations
To handle the extreme mechanical stress of regular ship-assist rotations, the deck outfit relies on premium European engineering.
Towing and Deck Hardware
The forward working deck is anchored by a high-capacity Ibercisa hydraulic towing winch featuring a single split drum with double brakes and clutches, boasting a brake holding capacity of 150 tonnes. Aft of the wheelhouse, the vessel utilizes dual Ibercisa anchor windlasses and a specialized Palfinger Marine deck crane (PK12000M) capable of safe working loads up to 1.7 tonnes at a 6.2-meter outreach.
Bespoke Fendering and Bulwarks
Recognizing that PSA Marine handles an incredibly diverse mix of maritime traffic, from ultra-large container ships (ULCVs) to low-profile oil barges, the bulwarks and fendering systems were custom-tailored during the engineering phase. The heavy-duty rubber configuration is geometrically optimized to mitigate rapid towline wear and absorb localized frictional energy during heavy SIMOPS or close-quarters pushing.
Regulatory Compliance and Classification
The PSA Nebula features fully automated, unmanned machinery space capability, enabling reduced operational overhead without compromising port-side safety. It was constructed to the following rigorous American Bureau of Shipping (ABS) notations:
ABS A1, Towing Vessel, BP (60MT), ABS ABCU, UWILD, ABS AMS, QR
- ABCU & AMS: Denotes centralized automated bridge control and automated machinery systems, enabling safer, highly responsive steering.
- UWILD (Underwater Inspection in Lieu of Drydocking): Specially outfitted hull and thruster setups that allow divers to conduct certified structural inspections while the vessel remains in the water, significantly extending operational uptime and reducing drydock overhead.
- Accommodation: Fully compliant with MLC 2006 regulations, featuring comfortable, noise-insulated quarters outfitted for a standard operational complement of up to 10 crew members (configured as 2 single officer cabins and 4 double crew berths).
With more than 100 Z-Tech designs now in service worldwide, this 16-ship milestone reflects the marine sector’s ongoing demand for compact, high-bollard-pull assets capable of mitigating risks in increasingly congested deep-water ports.
Robert Allan Ltd. (Naval Architects & Marine Engineers)
Founded in 1928 in Vancouver, British Columbia, Robert Allan Ltd. is Canada’s oldest privately owned consulting naval architectural firm. Over nearly a century of continuous operation, the company has established itself as an international authority in the design of commercial workboats, specialized service vessels, and high-performance harbor craft.
While its portfolio spans everything from ocean-going ferries to research vessels, the firm is globally renowned as the premier designer of high-bollard-pull harbor and terminal tugs, with thousands of its signature designs currently in active service worldwide.
Source: Robert Allan Ltd.