The ship went down without warning with the loss of all on board in the Pacific 800 miles off Japan in September 1980, the biggest single loss in British maritime history. Recently, an expedition has been scanning the sea-bed near the spot where oil was found, and this week massive sections of debris were discovered.
Within two years of the loss, Peter Ridyard, the father of one victim, told the Government of cracks found in the Derbyshire's sister vessels at a vital point where the stern and superstructure join the rest of the hull. The Department of Transport refused to hold an inquiry until 1986, when the Kowloon Bridge, one of the sister ships, broke up off Ireland.
When that inquiry eventually reported in January 1989, it said that in the absence of any wreckage, what happened would have to remain 'a matter of speculation'.
The ship was built by Swan Hunter on Teesside in 1976.
The pounds 380,000 expedition to locate the remains of the ship, financed by the International Transport Workers' Federation, has found wreckage spread across the sea-bed two-and-a-half miles down. The seven segments range in length between 18.6 metres and 46.4 metres. Their combined length adds up to 256.2 metres, which would be the length of the hull in front of the superstructure.
If the stern section broke off on the surface, it would have sunk to a location miles away.
Richard Flint, spokesman for the federation, said analysis by computer of the images of the seven pieces of wreckage, and their location, would show whether the ship had broken up on the surface, or when it hit the sea-bed. Photographs might show whether sections had snapped off sheer, or torn in a jagged break, giving further clues. All the data will be brought back to Britain for detailed study at the University of Cardiff.
A spokesman for Bibby Line Group, owners of the Derbyshire, who received an insurance payout at the time of her loss, said: 'We must abide by the official inquiry, which concluded that the Derbyshire foundered in extraordinarily heavy seas. Obviously, however, we will consider any relevant information that is obtained by the present search.'
Pressure was mounting on the Government yesterday to reopen the official inquiry. Jimmy Knapp, general secretary of the shipping union RMT, called for a new public inquiry.