Francis, who ran a military contracting company out of Singapore, was first arrested in 2013 during a federal sting operation in a San Diego hotel, after he was suspected of running a vast corruption scheme which involved some naval officers treated to food, drink and paid sex.
He pleaded guilty in 2015 to offering about US$500,000 in bribes to Navy officers to steer official work to his shipyards, carrying out work on US vessels that prosecutors say he overcharged the Navy for, to the tune of US$35 million.
Francis suffered numerous health problems, including kidney cancer, which led to him being released to house arrest in 2018 while acting as a cooperating witness for federal prosecutors.
He was due to be sentenced on Sep 22.
Four Navy officers have been found guilty in the case so far, while another 29 people, including naval officials, contractors and Francis himself, have pleaded guilty, US media said.