MANY panamax boxships that have been the workhorses of the Panama Canal stand to be put out of service as the first postpanamaxes move from Asia to the US east coast, says London's Loadstar.

Alphaliner statistics show that six vessels ranging from 6,000 to 10,000 TEU are due to arrive at the waterway between 30 June and 8 July, on six transpacific US east coast upsized services replacing nine strings deploying ships of up to 5,100 TEU - the previous Panama Canal maximum.

The first official postpanamax vessel to pass westbound through the canal's enlarged lock chambers will be the 9,443-TEU Cosco Shipping Panama (renamed for the historic occasion) on June 26, during the canal's inauguration ceremony.

Thereafter, the G6 alliance's new NYX will be the first of the upgraded transpacific east coast services to use the canal, when the 10,010 TEU MOL Benefactor arrives at Panama on June 30, en route to New York, Norfolk and Savannah.

The upsized services will leave seven Asia-east coast all-water strings still operating panamax containerships, but Alphaliner suggests that these could be upgraded "in the foreseeable future" depending on market conditions and the prospects of carriers to off-hire the incumbent vessels.