Careless talk, they used to say during the Second World War, costs lives. Careless handling of nuclear weapons – banging them about and dropping them like so much scrap metal – could cost a great deal more.

Two of Britain’s most serious nuclear weapons accidents in the 1980s were caused by continual lapses in safety procedures, and were much more serious than was admitted at the time. However, the Ministry of Defence continued to insist yesterday that there had been no risk to the public on either occasion.

Newly declassified documents obtained by New Scientist magazine detail the incidents in which the weapons were dropped or damaged while they were being moved.

The first accident happened on May 2, 1984, at the RAF base at Brüggen, Germany. A nuclear warhead was damaged in transit when its container slid off a wet trailer as it cornered. The warhead, still in its container, rolled on to the tarmac and was dented.

Brüggen base was shut down while the bomb was partially dismantled and scientists were flown from Britain to X-ray the warhead. It was eventually taken back to the Atomic Weapons Research Establishment at Aldermas-ton, Berkshire, to be decommissioned.

An MoD board of inquiry at the time concluded that the accident was caused by the “wrongful act” of failing to attach the bomb container to the trailer. It recommended that six ser-vicemen be disciplined.

The documents, obtained under freedom of information law, show that a regulation requiring bomb containers to be secured when being moved had been routinely ignored since October 1981. Brüggen’s commander at the time, whose name has been removed from the released report, admitted that the breach had become almost a standard operating procedure, despite being an “outrageously high-risk practice”.

The second accident occurred at Coulport naval base, Strathclyde, on December 3, 1987, when a faulty Polaris missile was being unloaded from the sumarine HMS Repulse. As it was being locked down on a trailer, a crane hoisted it into the air, causing it to swing wildly and to crash into the trailer supports.

According to the MoD inquiry at the time, the weapon suffered “adverse shock”. The report blamed broken controls on the crane, which had missed its full programme of mechanical and electrical checks.

If the crane had been properly maintained, the report concluded, “it is highly probable that the incident would not have occurred”.

The Ministry of Defence continued to insist yesterday that both incidents had been minor. They had been fully investigated to rigorous safety standards and, where necessary, procedures had been modified, a spokeswoman said.

“The MoD continues to maintain the highest standards of safety and security during the storage, transportation or deployment of nuclear weapons,” a spokesman said. “There has never been an accident involving UK nuclear weapons that has presented any risk to the public.”

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