WASHINGTON • American Airlines accidentally sent the wrong plane across the ocean from Los Angeles to Hawaii, a company spokesman has confirmed.

In the Aug 31 incident, first reported by transportation blogger Brian Sumers, a plane that was not authorised to fly long distances over open water made the flight - albeit safely - to Honolulu.

American Airlines spokesman Casey Norton said the airline was still looking into how the mix-up happened. He emphasised that the plane which made the trip, an Airbus A321S, is the same plane type as the one that was supposed to make it - an Airbus A321H - aside from not having an "Etops" certification, which requires the plane to carry additional equipment. "It has the same engine, same fuel tanks, same range," said Mr Norton on Sunday.

He added, however, that the A321H has extra medical oxygen - different from the oxygen masks that drop from the ceiling - in case of an in-flight medical emergency. It also has an additional fire- suppression canister.

Planes flying over water in an area where they will be more than an hour from a possible landing area are required to carry the precautionary equipment and the Etops authorisation certifying they are on board, Mr Norton said.

He said the Federal Aviation Administration was "immediately notified" of the incident when the company realised what had happened. The airline has revised its software to "properly identify (that) the correct aircraft" are flying on the correct routes.

Mr Norton said he was not aware of similar past incidents at American or other airlines.

AGENCE FRANCE-PRESSE