Boeing will delay first delivery of the 747-8 freighter by several months and add a fifth aircraft to the flight test fleet to correct a series of problems.
First delivery to 747-8F launch customer Cargolux is reset from late 2010 to mid-2011, Boeing says. The company has not disclosed any schedule changes for the 787-8 Intercontinental, the passenger-carrying variant expected to be delivered in late 2011.
The delay follows a series of "discoveries" that disrupted the schedule for completing certification testing on time: a low-frequency vibration that appears in "certain flight conditions" must be resolved, Boeing says.
Secondly, an inboard aileron actuator is not working as expected. Boeing says that neither issue requires structural changes to fix the problems.
"We understand the issues encountered in flight test and are working through the solutions," says Pat Shanahan, vice-president and general manager of programmes for Boeing Commercial Airplanes.
Delay to the 747-8F comes one month after Boeing pushed back first delivery of the 787 from late 2010 to the first quarter of 2011.
Boeing originally planned to deliver the first 747-8F in late 2009, but first delayed the programme in October 2008. That delay caused Boeing to take a $1 billion charge on the programme.
However, the new schedule setback "is not expected to have a material impact on Boeing's 2010 financial results", Boeing says.