Taiwanese line Evergreen has won an exemption to allow it to carry out the biggest boxship transit of the Panama Canal.
Its 14,424-teu neo-panamax Triton (built 2016), chartered from Costamare, will pass through the waterway on 15 May.
It is the first 20-row-wide containership to make the transit, Alphaliner said.
The vessel is 51.2 metres wide, but at 369m long, exceeds the maximum permitted length by 3m.
Triton is heading from Kaohsiung to Colon and then on to the US.
"The successful trial transit of Evergreen’s Triton could pave the way for more containerships of this size to be deployed on the Far East-US east coast route, allowing carriers to further increase economies of scale," Alphaliner added.
Vessels with 19 rows have passed through previously.
The Canal increased the maximum number of rows to 20 a year ago.
Canal authority ACP however stated that it would consider accepting ships of up to 369m on a case-by-case basis.
ACP already regularly accepts a series of 17-row-wide Maersk Line ships of around 11,000 teu and up to 367m in length.
Slots could be increased
The number of Panama Canal transits by neo-panamax ships has increased steadily since the new locks and the expanded canal were opened in June 2016, Alphaliner said.
"Currently, containerships account for 47% of all neo-panamax canal transits, with an average of 26 crossings per week (northbound and southbound)," it added.
There are currently 13 weekly liner services in the Far East-US east coast trade via Panama, 12 of which deploy neo-panamax ships of up to 14,400 teu.
ACP is also expected to increase the number of daily neo-panamax vessel transit slots, up from the current eight, Alphaliner said.
Demand has continued to increase, not only for containerships but also for LPG and LNG vessels.
In the global container fleet, there are currently 128 containerships with a 20-row beam that could transit the Canal.