JACKSONVILLE, Fla. – As the second sonar search for the missing cargo ship ended, the National Transportation Safety Board released another update Thursday, saying that the second of 13 side scan sonar searches did not find anything.
Side scan sonar systems use ultrasound technology to increase resolution of targets. Typically, a side scan sonar searches 60 to 160 feet wide at about 2 mph.
A U.S. Navy search team is tasked with finding the missing cargo ship El Faro. The ship's last known location is northeast of Crooked Island in the Bahamas. The waters there are about 15,000 feet deep.
"The Navy's mission will be to first locate the ship and, if possible, to retrieve the voyage data recorder -- commonly known as a black box," officials said in a statement.
The Jacksonville-based El Faro disappeared Oct. 1 while making its weekly cargo run to San Juan, Puerto Rico. The ship's 28 American crew members and five Polish nationals are presumed dead.
A properly working black box will emit a signal for 30 days, which means only a week remained upon the team's arrival before the batteries in El Faro's were scheduled to die.
Locating the container ship's VDR would likely provide insight into the crew's decision-making leading up to and during its ostensibly fatal encounter with Hurricane Joaquin.
Tote Services, the company that owns the 40-year-old El Faro, confirmed that several pieces of large debris that had washed ashore in the Bahamas came from the doomed ship.
As the search continues for the ship, three previous lawsuits have been filed against the parent company that owned the El Faro, Sea Star Line LLC, which owns TOTE Services and TOTE Maritime, the companies who operated the ship.
Thursday, a fourth lawsuit was filed against Sea Star, TOTE Services and TOTE Maritime on behalf of crewman Anthony Thomas, saying that the owners of the ship was unseaworthy, not fit for its intended purpose, not properly maintained and did not repair or eliminate the dangerous conditions on the ship.
The suit also said the El Faro was on a, "collision course," with Hurricane Joaquin, and when the ship lost power it was, "a cork in the sea," as the hurricane neared.
According to documents filed as part of the suit, 23 documented deficiencies were found on board the El Faro by the Coast Guard since 2003 and claims the owners of the ship acted with a, "flagrant malicious disregard," for the crews' safety.
The lawsuit also notes that Sea Star LLC pleaded guilty to federal price-fixing and racketeering charges in 2011, which pointed to, "A continuous disregard of rules and regulations for the sole purpose of seeking profits."