Archives

August 2012

Sun Mon Tue Wed Thu Fri Sat
      1 2 3 4
5 6 7 8 9 10 11
12 13 14 15 16 17 18
19 20 21 22 23 24 25
26 27 28 29 30 31  

Breaking: 747-8F first delivery delayed to mid-2011 (Update1)

| | Comments () | TrackBacks (0) |


NAGOYA -- Boeing's jumbo 747-8 freighter schedule has buckled again following an assessment of the cumulative impact of an underperforming aileron actuator and structural flutter.

The delay, which slips the first delivery to Cargolux from late 2010 to mid-2011, adding six months the already delayed delayed program, while providing another black eye to the Boeing at a time when it continues to work to restore its credibility with suppliers and customers following a string of delay announcements to the 747 and 787 programs.

Boeing says a fifth flight test aircraft will be added to the flight test program. The company did not disclose which production aircraft would serve in a flight test role, though Boeing already added a fourth, RC503, to the certification campaign in July.

The airframer first hinted at a potential slip to 2011 at the Farnborough Air Show, and slowly confirmed details as to the cause of the program's troubles.

The 747-8F flight test campaign, which kicked off on 8 February, has been beset by on-going technical discoveries, including a vibrating outboard landing gear door, and most recently two primary issues: a limit cycle oscillation (LCO) of the inboard aileron power control unit (PCU) manufactured by Nabtesco, which has now largely been resolved, and a 2.4Hz structural flutter that occurs at a mid-weight near cruise speed.

The airframer says: "while neither issue requires structural changes to the airplane, they have led to disruptions to certification testing, which the program was unable to offset within the prior schedule."
 
Boeing has tasked RC522 to test a fix for the flutter with a technique the company has dubbed the 'outboard aileron modal suppression system' or OAMS, an engineering law that is designed to dampen the flutter and improve the stability and control of the aircraft.
 
"We understand the issues encountered in flight test and are working through the solutions," says Pat Shanahan, Boeing vice-president, airplane programs.

Shanahan, who in addition to his responsibilities overseeing the company's commercial program, has taken a direct program management role on the 747-8, following the 28 August ousting of program vice president and general manager, Mohammad 'Mo' Yahyavi.
 
The schedule for Boeing's first 747-8I, currently in wing to body join, was not altered, with first flight and entry into service holding at first and fourth quarter 2011, respectively.

Previous delays to the 747-8F program were announced in November 2008 and October 2009.

0 TrackBacks

Listed below are links to blogs that reference this entry: Breaking: 747-8F first delivery delayed to mid-2011 (Update1).

TrackBack URL for this entry: http://www.flightglobal.com/cgi-bin/mt/mt-tb.cgi/173488

Cookies & Privacy