United Airlines will base the majority of its Boeing 747-400 fleet at its San Francisco hub from April 2013, as it focuses on improving the reliability of the fleet.

The Chicago-based Star Alliance member says that the concentration of spare parts and tooling at the airport will allow it to reduce maintenance issues ahead of the summer 2013 travel season, in an employee newsletter on 19 December.

"These changes will allow us to more effectively utilise aircraft downtime, and we have full inventory support through the maintenance base warehouse and support shops," says Chris Carrick, SFO line maintenance managing director at United, in the newsletter.

United will replace 747s with Boeing 777-200s on its Chicago O'Hare to Tokyo Narita flight from 3 January 2013, and its Chicago-Hong Kong-Singapore flight from March 2013, it says.

The airline will upgrade flights between San Francisco and Frankfurt, London Heathrow, Osaka Kansai, and Taipei to 747s from 777s as a result of the shift. It will also upgrade flights between Honolulu and Tokyo Narita to a 747 from a 777.

United will continue to use 747-400s on flights between Los Angeles and Sydney, Australia.

"These moves, along with other fleeting changes, give us the ability to focus resources where they can do more to support reliability across all of our fleets," says Barry Beacher, line maintenance planning managing director, at United in the newsletter. He adds that resources at O'Hare will focus on Boeing 767 and 777 checks.

Even with the changes, United's international capacity will decrease at both San Francisco and Chicago in June 2013 compared to a year earlier. According to Innovata FlightMaps Analytics, available seat kilometres (ASKs) at San Francisco will decline by 2.6% to 1,465 million during the period while capacity at Chicago will fall by 22.3% to 1,057 million.

The declines come even as the airline adds flights between San Francisco and both Paris Charles de Gaulle and Taipei, and between Chicago O'Hare and Monterrey (Mexico), Nassau (Bahamas), Shannon (Ireland), Thunder Bay (Canada).

United chairman and chief executive Jeff Smisek said in September that it plans to cut capacity by about 1% in 2013.

The carrier has 26 747-400s with an average age of 17 years in its fleet, according to Flightglobal's Ascend Online database.

Source: Air Transport Intelligence news