The 'Havkong' incident at Braefoot Bay Terminal by Aberdour, Fife. 23rd January 1993
The Bermuda registered LPG tanker Havkong, berthed at the Braefoot Bay Marine Terminal in the River Forth in fine weather on 23 January 1993. The ship moored alongside, in compliance with the terminal's Jetty Regulations, including those related to moorings. However the winch and fairlead positions aboard Havkong were such that, despite deploying lines in excess of those required, the final mooring pattern geometry resulted in only two lines contributing restraint against westerly winds.
At 18:50 hours, when Havkong had loaded approximately 6000 tonnes of a nominated 15 000 tonne cargo of butane, the Braefoot Bay area was subjected to an unusually violent squall. This squall produced a veering westerly wind with gusts in the order of 80 knots (92 mph) superimposed on a mean wind speed that reached 62 knots. The resulting additional loading on the mooring system was resisted only by the forward backsprings. The winch brakes for these were overcome and the ship began to move ahead along the berth driven by the wind. As she gathered momentum the loading arms reached their envelope limits and successfully disconnected with no spillage of cargo. The remainder of the mooring lines failed one by one as the load came upon them sequentially.
Havkong began to swing under the influence of both the wind and the last of the moorings and drifted eastwards, broadside to the wind. She cleared a ship on the other berth, which was loading ethylene, by approximately 20 metres. About eight minutes after breaking away her engine was ready for use and this was used to keep the ship in the deep-water channel as she drifted downwind while the anchors were prepared. She was eventually brought to anchor approximately one mile east of the berth. A pilot boarded her to assist and tugs arrived. With tug assistance the ship was manoeuvred out into the main channel and then to a designated anchorage. The incident was declared over at 22:55 hours when Havkong anchored in Kirkcaldy Bay.
The available evidence leads to a conclusion that Havkong grounded lightly, probably on two occasions, during the incident. However, no damage was done to the hull and her cargo containment remained intact. There were no injuries on board and no spillage of cargo. Damage to the ship was limited to some deformed rails near the manifold and minor damage to one manifold line. As a result of the ship's movement there was minor damage to the access gantry, loading arms and navigation light on the jetty.
The inadequacies in Shell Expro's system for dealing with high wind speeds did not in themselves contribute to the incident. However, they led to the highly unsatisfactory situation that when the Havkong broke free from its moorings, terminal staff were caught by surprise with the ship still loading normally, despite wind speeds above the limits specified for stopping loading and disconnecting.
Failings in technical measures
- Two companies - Shell Expro and Exxon, jointly operate the Braefoot Bay Marine Terminal, although each company has its own control room and delineated part of the terminal. This incident highlighted the poor communications between the Shell Expro and Exxon control rooms.
- Emergency Response / Spill Control: safety management systems
- The emergency plans prepared by Shell Expro considered fire, explosion and gas leaks, but not shipping incidents. There was confusion as to the implementation of the plan in this situation e.g. uncertainty as to whether the site alarm should be sounded. Staff were not adequately trained regarding their roles in an emergency situation.
- Emergency Response / Spill Control: emergency operating procedures / training
- The wind speed alarm was commonly disabled as it was considered a nuisance: An operator silenced it upon acknowledgement, but if the wind speed dipped below the alarm level and back above it (e.g. in gusty weather) it resounded.
- Control Room Design: human factors / ergonomic issues
- The instructions on when to stop loading due to high winds were unclear. Regularly received weather forecasts were not used for immediate operational decisions such as stopping loading.
- Operating Procedures: provision of comprehensive written operating procedures
- Despite the correct number of lines being used to moor the Havkong, the configuration and size of the ship meant that it did not give adequate restraint in the forward direction. The stern of the ship projected beyond the line of the dolphin line making the wire stern lines not practicable for use. Recommendations suggested that maximum vessel parameters for safe mooring at the jetty be specified.
- Design Codes - Jetties: vessel anchorage
Health and Safety Executive, 'Havkong incident: a joint report of the 'Havkong' incident at Braefoot Bay Terminal by Aberdour Fife on 23 January 1993', 1994.