Wing cracks found on ۷۸۷s in assembly

 TIN news:   Roughly 40 Boeing 787s still in production may have cracks within shear ties of a wing rib, the company says.
 
Boeing is inspecting aircraft that may have the condition on three assembly lines in Everett, Washington, and North Charleston, South Carolina.
“We are addressing affected airplanes as required,” Boeing says in a statement.
The issue is not expected to impact a plan to deliver 110 787s this year, Boeing says.
The cracks were discovered by the 787’s wing supplier, Mitsubishi Heavy Industries, Boeing says.
The Japanese supplier recently changed a manufacturing process that “may have led to hairline cracks in a limited number of shear ties on a wing rib in the 787”, Boeing says.
Shear ties, which attach the ribs to the wing skin, have disrupted 787 production before.
In 2010, Boeing discovered that the skin attachments in the 787’s rear fuselage had to be replaced or fixed.
The initial design of the 787 had failed to account for thermal fatigue loads on aluminium parts.
As a result, frequent cycles of cooling and warming in service could pry the shear ties away from the skin. Boeing fixed the problem by using thicker ties and radius fillers on future 787s, requiring 400h to install at suppliers and significantly more for aircraft in final assembly.
The new problem reported by Mitsubishi Heavy Industries, which was first disclosed by the Wall Street Journal, affects about 40 aircraft, Boeing says.
The Wall Street Journal reports that the aircraft affected are line numbers 151 to 193.
Flightglobal’s Ascend online database lists the following aircraft in that sequence:
 
151 Hainan Airlines
152 Japan Airlines
153 Norwegian
154 China Southern Airlines
155 Aeromexico
156 Royal Brunei Airlines
157 Kenya Airways
158 Air India
159 Japan Airlines
160 Air Canada
161 LOT Polish Airlines
162 Qantas
164 Ethiopian Airlines
165 Norwegian
166 Royal Brunei Airlines
167 Ethiopian Airlines
168 Ethiopian Airlines
169 Air New Zealand
170 Air Canada
171 Hainan Airlines
172 China Southern Airlines
173 British Airways
174 Air Canada
175 Qantas
176 Qatar Airways
177 British Airways
178 Norwegian
179 ANA - All Nippon Airways
180 Air India
181 United Airlines
182 Arkefly
183 Norwegian
184 Kenya Airways
185 LAN Airlines
186 United Airlines
187 British Airways
188 Qatar Airways
189 Qantas
190 Thai Airways International
191 Thomson Airways
192 Kenya Airways
193 Unannounced non-commercial customer