TRAFFIC SEPARATION SCHEMES
As yachties we are unlikely ever to follow a TSS, but those of us who sail in the English Channel and southern North Sea will be only too well aware of them. They are invaluable for keeping large ships safely apart, but they can be a frustrating obstacle for yachts. Happily, Rule 10 does give us some discretion which, if used wisely, can save a few passage miles.
There are three requirements for yachts, but only one is non-negotiable: a vessel of less than 20m in length or a sailing vessel ‘shall not impede the safe passage of a power-driven vessel following a traffic lane.’ ‘Not impede’ should be taken to mean ‘give way’.
Rule 10 (h) tells us to avoid a TSS by ‘as wide a margin as is practicable’. Up to you, but I think that a diversion for this reason is rarely ‘practicable’.
The crucial bit is open to quite wide discretion. It is in clause (c), which basically and sensibly encourages us to get across the TSS as quickly as possible. To achieve this, we should cross on a heading ‘as nearly as practicable’ at 90° to the flow of traffic. Clearly, the spirit of the Rule outranks our convenience; it is in everyone’s interest to avoid cluttering up the traffic lanes unnecessarily. If you are motoring in a light wind, there can be little excuse for not obeying the requirement (within, say, 10° or so if that would save time and distance).
When beating against the wind, you should choose the tack which most nearly satisfies the rule. This will invariably be more than 45° to the traffic flow, but even that may not be sufficient in areas of high traffic density. In which case it might be prudent to motor-sail and steer a course which more closely complies with the Rule.
Even if you are lucky enough to be able to sail at 90° to the traffic flow, you may still be adding unwelcome miles to your passage if your track would otherwise be at a significant angle to the TSS. So how far off 90° to steer? Again, it depends on the traffic and what you think you can safely get away with.
I have sailed across the Dover Strait TSS with hardly a ship in sight, at other times it has been like crossing the M25 on foot (which I have not actually tried).
Be aware that in the Dover Strait, Dover Coastguard (aka the Channel Navigation Information Service) will be keeping tabs on you and will not hesitate to bring you up with a round turn if you step too far out of line. The fines can be eye-watering, I’m told.
NARROW CHANNELS
Narrow channels (Rule 9) present less of a problem because the requirement is to keep clear of ships following the channel. See my definition of ‘do not impede’ above. The secret is to think like a big ship.
What may seem to be wide open water to you – the Solent or Thames Estuary, for example – may be very constraining to large vessels. Such ships will not be able to alter course for you, nor can they slow down much without losing steerage way. Listen to the local Vts/harbour Control and keep a very good lookout. If you remain outside the main shipping channels, you will be safe.
OVERTAKING
Yes, we all know that Rule 13 tells us that the overtaking vessel shall keep out of the way of the vessel being overtaken. Fine in theory, but not so clear in practice if you are the one being overtaken. In our yachts, we might typically be making 5 knots through the water while a large overtaking ship might be travelling at three to five times that speed and keen to arrive at her next port on time.
Once again, this is where Rule 2 comes to our aid: use your common sense. If you can make your intentions perfectly clear – perhaps by a substantial alteration of course – you should be able to increase the CPA (closest point of approach) without worrying the overtaker. If not, you just have to make sure that you have been detected. By night, you could illuminate your sails; by day, this is the one time when a VHF call (preferably by DSC) might possibly be justified. You are not suggesting a course of action, just making sure you have been seen.