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Tug Escort and Bollard Pull: Planning Assist for Laden Tankers
For a laden tanker in confined water, the escort tug is the last line of defense if steering or propulsion fails. Here's how escort differs from assist, what bollard pull actually buys you, and why the tug plan belongs in the transit record.
When a laden tanker transits a confined waterway, the tugs around her are not a convenience — in many districts they are a regulatory and practical last line of defense against a steering or propulsion failure at the worst possible moment. Coordinating those tugs is part of the pilot's plan and part of the dispatcher's job. This guide covers the distinction between escort and assist, what bollard pull means, and why the tug plan belongs on the transit record rather than in someone's head.
Escort is not assist
The two words describe different jobs:
- Assist tugs help a ship maneuver — pushing and pulling to berth, unberth, or turn. They do their work at low speed in the immediate vicinity of the dock.
- Escort tugs accompany a ship at transit speed through a sensitive stretch, positioned and capable so that if the ship loses steering or propulsion, the tug can arrest a sheer or slow and steer her before she reaches trouble. Escort is about the failure that has not happened yet.
Escort is where the demanding numbers live, because an escort tug has to be able to control a large, fast-moving, laden vessel using its hull and lines — a fundamentally harder task than nudging a ship alongside.
What bollard pull buys you
Bollard pull is the static pulling force a tug can exert, measured in tonnes. It is the headline spec of a tug's capability, and tug plans are written in terms of it: a district or a terminal may require a minimum aggregate bollard pull for a vessel of a given size, or a specific escort-capable tug above a draft or tonnage threshold.
But bollard pull is not the whole story for escort work. At transit speed, what matters is the tug's steering and braking force — the dynamic forces an escort tug generates with its hull and skeg, which can exceed its static bollard pull. The design of the tug (tractor, ASD, the escort notation) determines how much useful force it can apply at speed and at angle. The plan has to match the right kind of tug, not just enough raw bollard pull.
What the plan has to specify
A complete tug plan, agreed in the Master-Pilot Exchange, covers:
- How many tugs and their bollard pull (and escort capability where required).
- When each is made fast and where — and whether tethered or free-running for the escort leg.
- The escort stretch — where escort begins and ends along the transit.
- Contingency — what each tug does if steering or propulsion is lost.
- Communications — channels and who directs the tugs.
Much of this is driven by the district's rules, the terminal's requirements, and the vessel's condition that day — which is exactly why it should be captured per transit, not assumed from the last call.
Why the tug plan belongs in the transit record
Three reasons to record it rather than carry it verbally:
- It is a compliance artifact. Where escort or minimum bollard pull is required, a record that the right tugs were ordered and made fast is the evidence that the requirement was met.
- It coordinates the parties. The tugs, the terminal, and the dispatch desk all need the same plan; a shared record beats three phone calls.
- It feeds the timing. Tugs have to be ordered and staged to meet the ship; the tug plan is part of the dispatch sequence, not a separate errand.
How Binnacle Passage handles it
Binnacle Passage carries a tug order on the transit: how many tugs, bollard pull, escort vs. assist, and a status that advances from requested → confirmed → made fast → released, each step stamped. Because it lives on the transit alongside the MPX, the ladder check, and the eventual billing, the tug plan is part of one continuous record of the job — ordered in time, agreed in the exchange, and evidenced afterward.
It does not set your district's tug requirements; it makes the plan you've agreed an explicit, coordinated, recorded part of the transit.
The bottom line
For a laden tanker, escort tugs are insurance against a failure that has not happened, and the plan is written in bollard pull and escort capability — but the right kind of tug matters as much as the raw number. Specify it per transit, agree it in the exchange, order and stage the tugs in the dispatch sequence, and keep the plan on the record. It is both a safety control and a compliance artifact, and it belongs with the rest of the job.
This article is general information. Tug escort and bollard pull requirements are set by federal and state regulation, terminal rules, and your association's procedures.
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Binnacle AI is not affiliated with, endorsed by, or sponsored by the U.S. Coast Guard. CFR citations refer to the current Code of Federal Regulations as of publication; confirm against eCFR before filing or inspection. This article is informational and is not legal advice — consult a qualified maritime attorney for specific regulatory questions.