Classification
- Incident Type: Sinking
- Severity: High
Vessel Details
| Field | Value |
|---|---|
| Vessel Name | MV Derbyshire |
| Vessel Type | Bulk Carrier / OBO carrier |
| Flag State | United Kingdom [GB] |
| IMO Number | Not confirmed in reviewed report sections |
| Gross Tonnage | Not reported in reviewed report sections |
| LOA (m) | 294.1 |
| Breadth (m) | 44.2 |
| Year Built | 1976 |
| Owner/Operator | Bibby Tankers Ltd |
| Crew Size | 42 crew members and 2 wives |
Incident Details
| Field | Value |
|---|---|
| Date | 1980-09-09 |
| Location | Pacific Ocean, about 350 miles southeast of Japan |
| Region | Pacific Ocean |
| Coordinates | 26.5000, 128.0000 |
| Fatalities | 44 |
| Injuries | 0 |
Key facts
- Derbyshire was within a few days of arrival at Kawasaki when it encountered Typhoon Orchid.
- At 03:00 UTC the vessel reported being hove to in force 11 winds and 30-foot waves; its last radio message was sent at 10:19 UTC.
- By about 17:00 UTC, significant wave height was estimated at 10.86 m and wind speed exceeded 56 knots.
- Sustained green-water loading destroyed some or all foredeck ventilators and air pipes, allowing flooding of forward spaces.
- Forward flooding increased trim by the bow and exposed the No. 1 hatch cover to loads that likely exceeded its collapse strength; Nos. 2 and 3 then failed sequentially.
- All 44 people aboard, including two wives of crew members, died. The exact moment of sinking was not observed.
Narrative
MV Derbyshire was a four-year-old oil/bulk/ore carrier owned by Bibby Tankers Ltd. It was carrying iron ore concentrates from Quebec to Japan and was within a few days of arrival at Kawasaki when Typhoon Orchid developed across its route. At 03:00 UTC on 9 September 1980, the vessel reported being hove to in a violent storm with force 11 wind and 30-foot waves. Its last radio message was transmitted at 10:19 UTC.
The re-opened formal investigation examined weather data, model tests, wreckage, and competing explanations for the loss. By about 17:00 UTC, significant wave height in the storm area was estimated at 10.86 metres and wind speed exceeded 56 knots. The report concluded with reasonable confidence that sustained green-water loading destroyed some or all of the foredeck ventilators and air pipes. Seawater then entered forward spaces, including the bosun's store, machinery space, and probably a ballast tank, causing trim by the bow.
As the bow settled, green-water loading on the No. 1 hatch cover increased until the cover likely exceeded its collapse strength. Flooding of No. 1 hold increased the bow trim further, causing the No. 2 and No. 3 hatch covers to fail sequentially. The vessel then became irretrievably lost. The exact time of sinking was not observed, and the wreck was later located in deep water about 350 miles southeast of Japan.
The re-opened investigation rejected the earlier theory that the crew had left the foredeck bosun's-store hatch lid inadequately secured. Wreckage evidence was also inconsistent with Frame 65 cracking having contributed to the loss. The report concluded that the forward hatch-cover strength requirements in the 1966 Load Line Convention were seriously deficient by contemporary safety concepts for vessels of Derbyshire's size. All 42 crew members and two crew members' wives died.
Sequence of events
| Date/time | Event |
|---|---|
| 1980-09-09 03:00 UTC | Derbyshire reported being hove to in force 11 winds and 30-foot waves. |
| 1980-09-09 10:19 UTC | The vessel sent its last radio message. |
| 1980-09-09 about 17:00 UTC | The investigation's weather analysis placed significant wave height at 10.86 m and wind above 56 knots. |
| 1980-09-09 onward | Green-water loading and forward flooding led to sequential hatch-cover failures. |
| 2000-04-05 to 2000-07-26 | The re-opened High Court formal investigation hearing was held. |
Contributing factors
| Factor | Evidence status | Description |
|---|---|---|
| Sustained green-water loading | Confirmed finding | Heavy seas destroyed foredeck ventilators and air pipes and loaded the forward hatch covers. |
| Forward-space flooding | Confirmed finding | Water entering the bosun's store, machinery space, and probably a ballast tank caused trim by the bow. |
| Sequential hatch-cover failure | Confirmed finding | The re-opened investigation concluded that No. 1 failed first, followed by Nos. 2 and 3 as flooding increased. |
| Inadequate forward hatch-cover strength | Confirmed finding | The report found the ILLC 66 strength requirements seriously deficient for similar bulk carriers by contemporary safety concepts. |
| Crew-securement theory | Rejected finding | The re-opened investigation rejected the earlier conclusion that the bosun's-store hatch lid had been left inadequately secured. |
Investigation
The High Court conducted a re-opened Formal Investigation under the Merchant Shipping Act 1995. It concluded with reasonable confidence that green-water loading caused forward flooding, trim by the bow, and sequential failure of the No. 1, No. 2, and No. 3 hatch covers. The report found no fault by the master, crew, or routeing agency in encountering the storm and rejected alternative crew-fault and Frame 65-cracking theories. It did not establish the exact moment of sinking or provide gross tonnage, direct damage, or economic-loss figures in the reviewed sections.