George Sansom, 42, the cousin of ex-England football star Kenny Sansom, was in charge of marketing the drug in Britain while a "money man", Coleman Mulkerrins, 53, masterminded the meticulously planned operation.
At Snaresbrook Crown Court in east London, Judge Andrew Brooks told the pair drug trafficking had become a "multi-billion pound industry taken over by serious criminals".
Jailing them, he said he had a duty to protect young people who may be tempted by the "dreadful drug" and cited the recent case of Leah Betts who died after taking a ecstasy tablet at her 18th birthday party.
The defendants, flanked by seven prison officers, showed no emotion when they were sentenced.
The court heard that Mulkerrins put up pounds 200,000 in June 1992 to buy a ship used to transport cocaine from Venezuela. The vessel was tracked until it docked at Charlton, south-east London, in November 1992, from where the 795kg consignment - one of the biggest ever seized - was taken to a lock-up unit in nearby Deptford, said Anthony Glass QC for the prosecution.
The cocaine, which had been subject of a 12-month surveillance operation involving police and Customs, was then seized.
At that stage, six men, mainly members of the ship's crew, including captain Barry Murphy, 43, were arrested.
However, following a pounds 2m trial at Southwark Crown Court in December 1993, they were all acquitted by a jury of being knowingly concerned in the importation of the drugs.
Mulkerrins was arrested last May while Sansom, who called his famous cousin as a character witness in his trial, had to be extradited from Tenerife, Spain. In June this year, a jury hearing Mulkerrins' and Sansom's trial at Snaresbrook Crown Court was given round-the-clock police protection. But a month into the trial the jury was discharged after complaints of "unwarranted attention".
The case was transferred to Norwich Crown Court where the jury convicted Mulkerrins and Sansom of being knowingly concerned in the illegal importation of cocaine.
Mulkerrins, of Twickenham, south-west London, and Sansom, of West Dulwich, south-east London, denied the charge and maintained they had nothing to do with the drugs plot.
The judge said: "Had it not been for the vigilance of the Metropolitan Police and Customs and Excise this massive quantity [of cocaine] would have undoubtedly found its way onto the streets of this country and thousands of vulnerable young people would have suffered as a result ...
"Those who choose to become involved in the trafficking of class-A drugs must be told in the clearest possible terms that in dealing with them the courts will show little or no mercy."Reuse content