Safety when handling tugs


CHIRP has received a number of reports relating to communication and procedures when handling tugs and during mooring operations. Two high risk incidents are detailed below.

What the reporter told us (1)

The assisting tugs in this East African port utilize vessel-provided lines when docking and undocking.  The docking pilots routinely ask for the best line and then wait while the tugs make fast.  Communication with the tugs – when making fast, letting go or working the vessel – is generally conducted in Swahili.  While making fast, particularly on departure, the tugs take a heavy strain on the line as it is paid out to them, and there is much screaming from the tug for “Slack, slack!”  The vessel will be instructed to make fast the line while the tug is still moving away from the vessel, and there is still a heavy strain on the line.  This type of evolution puts crew members involved at risk of serious injury.

While this situation was last observed on 28 December 2016, it has been witnessed by the reporter for at least the past 7 years.

The reporter advised the following lessons have been learned:

  1. Request pilots to converse in English, or confirm their orders to the tugs in English as soon as they are given, so the bridge team can maintain awareness.
  2. Closely monitor the evolution when making tugs fast. The Chief Officer or Master should monitor the process and bring any unsafe actions to the pilot’s attention.
  3. Pilots in this port do not appear cognizant of the effect of reduced manning on the speed of mooring evolutions. With only three crew forward and three aft, multiple tasks (i.e. heaving in mooring lines and making fast the tug) cannot be completed at the same time.
  4. Deck officers on the bow and stern have been instructed to put the eye at the bitter end of the tug line on a bitt to ensure the tug does not pull the entire line off the vessel, as has happened in the past.
  5. Crew on the bow and stern are instructed to stand clear of the line as it is being paid out, and maintain control of the line by having at least one round turn on a bitt.
  6. Crew are instructed that, if excessive force is put on the line by a tug, they must get clear and take cover. Tug lines have parted in this port in the past when sudden loads were placed on them

What the Third Party told us (1)

CHIRP wrote to the Director General of the port in question and also the Port Manager. There was no response and the matter was followed up, but still without a response, which from a government department is most disappointing.


What the reporter told us (2)

Vessel commenced unmooring operations from berth No 2 of the terminal at 05:24 hrs/lt.

Following the unmooring plan agreed with the pilot during the Master/Pilot exchange process, headlines and stern lines were released first, and then the breast lines.

During the last stages of unmooring the pilot ordered the tug skippers to pull the vessel away from the dock without first releasing the spring lines. During the pulling operation, the forward spring mooring tail parted.

Parted mooring tail following recovery of mooring line

The investigation noted that:

  • According to the vessel’s report the parted mooring tail had been in service for 12 months with 798 working hours, and was in very good condition. The minimum breaking load (MBL) was 146T.
  • All related machinery and equipment was in good operational condition, and tested successfully prior to departure.
  • A risk assessment had been completed and the hazards and risk control measures relating to the mooring and unmooring operations had been addressed.
  • The pilot instructed the tug to pull without informing the Master or the bridge team.
  • The pilot instructed the tug skippers to start pulling although the spring lines had not been slacked or released.
  • This action was not noticed by the Master or OOW immediately.
  • At the time of the incident the wind was reported as SW Force 2.
  • No damage was caused to the vessel or terminal facilities. No injury occurred.

It was concluded that the incident was caused due to improper instructions from the pilot to the tug skippers, inadequate monitoring of pilot orders by the vessel’s Master and OOW, and inadequate communication procedures between the pilot and the bridge team.


CHIRP Comment

Having discussed these reports, the Maritime Advisory Board recommends the use of best and now common practice whereby only the use of tugs lines is permitted – a system utilised in the vast majority of ports. The Board emphasised that handling lines with tugs involves risk which can be mitigated with proper planning and that specific guidance is needed for ships crews when ships lines have to be used for tug operations. This includes;

  • The need for a comprehensive exchange of information between the Master and Pilot before securing tugs, including when and how tugs will take/release the lines.
  • Similarly, the personnel involved in handling the line(s) need to be properly briefed.
  • Mooring crews should put the eye of the bitter end of the tug line on a bollard, and then ensure the tug does not pull the entire line off the vessel in an uncontrolled manner. Effective communication is essential in this respect.
  • Mooring crews should be instructed to stand clear of the line as it is being paid out and maintain control of the line by at least one round turn on a bollard.
  • Mooring crews should be instructed that once the tug is fast they must keep well clear; and if excessive force is put on the line by a tug, they must take cover. Tug lines have often parted in the past when sudden loads were placed on them.

Although the port is not named in the report it is known, and there is absolutely no tidal or other reason for the tugs to start pulling off before all lines are sighted and clear. Thus, this case would appear to be about communication, complacency, and (possibly) time pressure. It is absolutely essential that relevant personnel are clear of tugs’ lines prior to the tugs pulling/pushing, so effective communication between the Pilot / Master / Bridge Team and the mooring stations is vital.

Effective communication is vital throughout all mooring and tug handling operations. Where English is not the common language then pilots communicating in their native tongue to the tugs is advisable, but the context of the discussion must be reported to the Master and thence to the mooring stations, preferably before the instruction is given.

People are still being killed and injured in mooring and line handling operations, so the foregoing is not simply common sense – it is essential advice.

Report Ends

1 Comment

  • Nigel Meek

    In my ongoing career as cargo ship navigating officer, tug mate, tug master, pilot, senior pilot, 46 years and counting, I have passed ships’ mooring lines to tugs, taken wire tow lines without eyes from tugs, used combination wire and rope tail towlines as a tug master and now as a pilot am using high modulus polyethylene (HMPE) tow lines invariably supplied by the tug. I have watched ships’ mooring lines break under load and spring back at the tug, I have seen wires slip before being properly secured around ship bitts and flail around under load. I have seen a wire/rope combination part and spring back and dent the steel accommodation.
    Modern HMPE tow ropes are very light weight, always fall flat without recoil when broken and are at least as strong as steel. They are supplied from tugs, invariably with a large eye for dropping over the bitts. They are payed out from the tug via a winch and brake arrangement and are at all times controlled very safely by the tug.
    This is purely a financial cost/benefit discussion wherein a range of health and safety opinions and regulatory environments may be encountered in different parts of the world.