Defense/Aerospace Industries

[DewDiligence]

Boeing Discloses New Dreamliner Flaw

http://online.wsj.com/article/SB20001424052748704314904575250944040434162.html

›MAY 18, 2010
By PETER SANDERS

Boeing Co. said it encountered another design flaw on its overdue 787 Dreamliner jet, and that the problem had been one of the factors that forced an ongoing five-week delay in shipments of fuselage parts.

The Chicago company confirmed Monday that it had identified weakness in aluminum parts called shear ties during testing in December. The shear ties connect the plane's frame to its fuselage skin, which is made of composite materials. Boeing found during its analysis process that the shear ties could peel back from the fuselage skin after exposure to extreme hot and cold temperatures and could lead to structural failure.

Boeing said it will strengthen existing shear ties on planes that have already been built or are in construction at factories around the world. A fix that may involve the design of thicker ties will be implemented on new planes being built later this year.

In late April, the jet maker asked suppliers to suspend deliveries of 787 fuselage parts to its final assembly factory in Everett, Wash., until early June. At the time, the company said the delay was to give some of its far-flung suppliers a chance to catch up on necessary work and to deal with a shortage of certain spare parts [i.e. they lied]. But on Monday, after the issue was reported on FlightBlogger, an aviation-industry blog, Boeing said the problem with the shear ties was partly responsible for the slow down.

Monday's disclosure is the second time Boeing has been forced to disclose design flaws with the new jet that is already more than two and a half years behind schedule. The delays have cost Boeing billions of dollars in penalties and the cancellation of some orders.

Last year, the company was forced to postpone the start of its ambitious flight-test program by six months after ground tests revealed that the area where the plane's wings met the body had failed stress tests. Those areas have since been strengthened and Boeing says the Dreamliner passed subsequent tests.

Boeing said the ties problem will not affect its flight-test program or the planned delivery of the first 787 to launch customer All Nippon Airways Co., sometime before the end of this year.

Separately, Boeing said it would increase production in early 2012 of its best-selling narrowbody 737 to 34 planes a month from 31.5 now.‹