A Cathay Pacific Airways pilot has been fired for buzzing a U.S. airfield without permission.

The Hong Kong-based airline says the incident occurred in Washington state as the airline was taking delivery of a Boeing 777-300ER passenger jet.

The carrier - which would not identify the pilot - says it is still investigating the Jan. 30 flyby event at the Boeing plant near Seattle.

Cathay spokeswoman Carolyn Leung says the pilot was dismissed last week because he did not seek or obtain approval for the flyby, which has been done several times before at air shows with the airline's permission.

An airline statement said another pilot on the plane has also been subjected to disciplinary proceedings, but no details were disclosed.

Images of the stunt were posted on YouTube and the website of a Seattle-area plane spotter, Matt Cawby.

Hong Kong's South China Morning Post reported on February 24 that the airline's chairman, Christopher Pratt, was on the plane when the pilot, Capt. Ian Wilkinson, swooped back over the Boeing plant shortly after taking off.

The 777-300ER, with a list price of US$264 million, is almost 74 metres long and weighs about 317 tonnes.