A programme launched roughly two years ago by American Airlines to improve the aerodynamics of its Boeing MD-80s is progressing, with 51 aircraft now flying with new tail cones and a further 40 earmarked for retrofit.

The US major is retrofitting a total 91 of its 300-strong MD-80 fleet that do not have low-drag tail cones. Manufactured at the carrier's Tulsa maintenance base, the new tail cones consist of numerous layers of Kevlar.

Employees at Tulsa suggested that American manufacture the tail cones itself, rather than purchasing them from Boeing. "While Boeing was charging about $270,000 per tail cone, American employees found they could construct the same part for around $35,000 per tail cone," says the carrier.

American expects the retrofit will increase its fuel-conservation efforts by more than 3.8 million litres (1 million USgal) a year. Additionally, the airline says it will reduce carbon dioxide emissions by more than 9 million kg (20 million lb).

The retrofits comprise part of American's Fuel Smart initiative, which also calls for the carrier to add winglets to its aircraft. Winglet installations on all of its Boeing 737s are complete, while the 757s will be complete by the end of 2008.

American is also the launch customer of Aviation Partners Boeing's 767-300ER winglet. Under a pact reached in April, American will remove one of its 767-300ERs from service and lease it to the manufacturer for an eight-month flight-test certification programme, which is scheduled to begin in January 2008.

Source: FlightGlobal.com