To avoid collision with a ship ahead it is often preferable to ram the ice on one side of the channel if it is sufficiently thin to embed the bow without damage rather than risking going astern. Due to unexpected conditions or in emergency an icebreaker may stop or manoeuvre ahead of an escorted ship without any warning signal. Towing All icebreakers are fitted with towing winches with a towing wire reeled on each winch drum. Each towing wire, which has at it end an eye and a hauling-in pendant, is led over an indentation in the stern. The winches are sited as far forward as possible to minimise the vertical angle of tow, and to allow the stem of the ship being towed to be hove close into the indentation in the icebreaker's stern.
Icebreakers tow at either long or short stay.
When certain icebreakers tow at short stay, the towed vessel is hauled close-up into an indentation or yoke at the icebreakers stern, and for them, this is the most usual method, particularly when the ice is uneven and the icebreaker's speed varies. Certain vessels, however, because of their size or the construction of their stem, can only be towed at long stay. When an icebreaker decides to tow, the assisted ship must immediately prepare to take on board and secure quickly the towing wires, particularly if there is ice screwing or ice pressure. Heaving lines passed to the after deck of the icebreaker are used to bring inboard the hauling-in pendants of the towing wires. These are brought to the escorted ship's capstan, so that the eyes of the towing wires can be hauled aboard and secured.