Why Routeing and Reporting Exist
Collisions and groundings remain the leading causes of total loss in merchant and large-yacht operations. IMO-adopted routeing systems separate traffic, reduce encounter rates in confined or high-density waters, and give coastal states situational awareness of vessels that could threaten their SAR resources or marine environment. As Master, your obligation is not merely to comply — it is to understand which systems apply, when your yacht triggers them, and to make a documented decision where discretion exists.
The Regulatory Framework
Ships' routeing is governed by SOLAS Chapter V, Regulations 10 (routeing) and 11 (ship reporting). IMO Resolution A.572(14) (general provisions on ships' routeing) and the IMO publication Ships' Routeing set out the adopted schemes. Compliance with Traffic Separation Schemes (TSS) adopted by IMO is mandatory under COLREGS Rule 10. MSN 1858 establishes which certificates and operational requirements apply to UK-coded yachts, underpinning the competency standard you are being assessed against.
Ships' Routeing — Command Decisions
Traffic Separation Schemes (TSS) Rule 10 COLREGS applies without GT threshold. A yacht of any size transiting an IMO-adopted TSS must use it correctly: join or leave at the ends or at the side, proceed in the appropriate lane, cross at right angles if crossing. The Master's decision to cut through rather than sail around must be weighed against the added distance, weather, and the statutory obligation.
Key command pitfalls: failing to cross at as near to a right angle as practicable; anchoring in a lane or separation zone without necessity; not keeping clear of separation zones.
Areas to be Avoided (ATBAs) and Recommended Routes ATBAs may be mandatory or advisory. The Master must identify the status from the current edition of Ships' Routeing or the relevant chart and ALRS, and record the decision if electing to transit one that is advisory.
Mandatory Ship Reporting Systems (SOLAS V/11)
IMO has adopted mandatory reporting systems for specific areas (e.g., MAREP in the Dover Strait, various coastal systems). Participation is mandatory for vessels meeting the stated criteria — these are typically defined by GT, length, or cargo type, not by flag alone. Before each passage the Master must:
- Identify which reporting systems cover the route.
- Determine whether the yacht meets the participation threshold.
- Establish the reporting format, VHF working channel, and positional report intervals.
- Brief the bridge team and confirm the system is set up in the passage plan.
VTS (Vessel Traffic Services) under SOLAS V/12 are distinct: they are shore-managed services the Master engages with, but ultimate navigational decision-making remains with the Master.
Passage Planning Integration
A passage plan that does not record the TSS, mandatory reporting obligations, and any ATBAs along the route is deficient. In an incident investigation, the absence of this from the plan — and from the bridge log — is the Master's professional and legal exposure. Document the system, the threshold assessment, and the call sign or MMSI used for reports.