Inherent instability, poor safety equipment and an unqualified crew all contributed to the death of 15 Britons, including three Midlanders, when a party boat capsized in Bahrain, an inquest ruled yesterday.

Patricia Doyle and her daughter Roslyn, a teacher from Hagley, in Worcestershire, perished just hours after they were reunited in the Gulf state when the ill-fated Al Dana vessel set sail on March 30.

Mrs Doyle, aged 64, had arrived in the country that morning to visit her 35-year-old daughter, who was working as an English language teacher with the British Council. They were were among the 130 revellers who had boarded the wooden dhow before it sank in calm waters.

Birmingham-born William Nolan, a 50-year-old projects director for a World Trade Centre being built in Bahrain, was among the 58 who died when the boat sank.

The revellers had been celebrating the completion of the first stage in constructing the centre's towers. Coroner Alison Thompson, sitting at West London Coroner’s Court, yesterday recorded a narrative verdict for the nine Britons and one German whose bodies were repatriated to the UK via Heathrow.

Ms Thompson cited a Bahrain report into the disaster which found that the vessel had been "dramatically altered" with a superstructure built on to the traditional boat, destabilising it.

The boat had been further weighed down with air conditioning units, a kitchen, fridges and a generator, along with the 130 passengers.

The inquest, which was opened on October 26, heard that escape doors on the lower deck were locked and lifebuoys were fastened to handrails with nylon ropes.

It also heard how several guests left the boat before it set sail as it felt so unstable. In all ten cases, the cause of death was given as drowning but Ms Thompson put off her verdict until December 7.

Abdullah al-Kobaisi, the owner of the boat, and Rajendrakumar Ramjibhai, the captain, face criminal charges in Bahrain. Many of the survivors and relatives are taking legal action to fight for compensation.

After the inquest Clive Garner, of Birmingham-based law firm Irwin Mitchell which is representing the families of the deceased and victims of the tragedy, said: "The coroner concluded that the capsizing was due to a number of serious errors by those very people responsible for passenger safety.

"This inquest has been helpful in answering a number of important questions relating to what went wrong. "However, further questions need to be answered to ensure that justice is done for the victims of this terrible tragedy and so that lessons can be learned to avoid a similar disaster in the future."