Friday, March 7, 2014

Wall Street Journal: Undelivered 787 to be inspected for wing cracks

The Wall Street Journal's Jon Ostrower reported today that a change in the manufacturing process in the Mitsubishi built wings for the 787 may cause hairline cracks to develop.

This is another potential issue in a whole list of issues dating back to 2007 that have plagued the 787.  Jon identified the 787s affected as aircraft LN 151 to LN 193 inclusive.  Boeing said that some of the 43 aircraft have cracks and some do not while others have yet to be inspected.  According to the database that I have compiled, most of the aircraft have been built or are under going final assembly.  Some of the wings that are still in Japan are assigned to the later line numbers.

Line Number Customer
LN151 Hainan Airlines
LN152 Japan Airlines
LN153 ILFC/Norwegian
LN154 China Southern Airlines
LN155 ILFC/Aeromexico
LN156 Royal Brunei Airlines
LN157 Kenya Airways
LN158 Air India
LN159 Japan Airlines
LN160 Air Canada
LN161 LOT Polish Airlines
LN163 ILFC/Aeromexico
LN164 Ethiopian Airlines
LN165 Norwegian
LN166 Royal Brunei Airlines
LN167 Ethiopian Airlines
LN168 Ethiopian Airlines
LN169 Air New Zealand
LN170 Air Canada
LN171 Hainan Airlines
LN172 China Southern Airlines
LN173 British Airways
LN174 Air Canada
LN176 Qatar Airways
LN177 British Airways
LN178 ILFC/Norwegian
LN180 Air India
LN181 United Airlines
LN182 TUI Travel (Arke)
LN183 ILFC/Norwegian
LN184 Kenya Airways
LN186 United Airlines
LN187 British Airways
LN188 Qatar Airways
LN190 ILFC/Thai
LN191 TUI Travel (Thomson)
LN192 Kenya Airways

According to the Journal, Mitsubishi changed the way it manufactured the wings. However this process creates a problem which "stems from fasteners used to connect aluminum shear ties on the wing ribs to the carbon fiber composite wing panel, according to two people familiar with the situation."
"The fasteners were over-tightened without the use of manufacturing fillers, compressing a gap in the structure and in some cases caused hairline cracks of less than an inch. If left unchecked can cause unintended stress on the jet's structure and could lead to further damage. 'We understand the issue, what must be done to correct it, and are completing inspections of potentially affected airplanes. We are addressing affected airplanes as required,' said the Boeing spokesman."

Of the 43 aircraft that are affected, 7 have flown production flights and 18 have completed final assembly. There are a further 14 undergoing final assembly both at Everett and North Charleston.  Another 11 are waiting to enter final assembly.  These 11 all should enter the final assembly process over the next 5 weeks or so.

It is unclear what impact this would have on the delivery schedule but Boeing is saying that deliveries should be unaffected.  Furthermore it is unclear what changes Mitsubishi or Boeing will implement to ensure that these crack don't occur again. 


Pete Templin said...

Your article says this is "another potential issue". Honestly, there's a potential issue with every component, every fastener, every drop of paint. If optimizations don't occur, we never get planes as advanced as, hmmm, the 737-300, the 737-600, or perhaps even the 787. It's a bump in the road, and it'll take time to sort through, but it's not a plague.

Pete Templin said...

Your article says this is "another potential issue". Honestly, there's a potential issue with every component, every fastener, every drop of paint. If optimizations don't occur, we never get planes as advanced as, hmmm, the 737-300, the 737-600, or perhaps even the 787. It's a bump in the road, and it'll take time to sort through, but it's not a plague.

nskiwi said...

So this process must of been a way for mitsubishi to speed up production to meet goals. I cant decide if this is just a case of bad luck or someone dropped the ball,either way this dosnt look good for boeing and the 787 program being in the spotlight with media,these problems will always be re hashed and put out there time and time again by media so the 787 is going to have the bad rap for along time to come,i just hope the 777x will be a different story

Jim Lang said...

I am wondering if Boeing has been aware of this for the past 2 months, and has the been primary reason for the slowdown in production, rollout and delivery...?

Darrell Sawyer said...

But you must remember that the media doesn't sell airplanes to airlines. The media articles are for non-decision makers (like you and me) and for stock speculators. Airplanes (regardless of what the media has to say about specific models) are purchased based on whether or not the specific model will potentially turn a profit for the airline. Airline decision makers know a lot more about any airplane model than the media does.

ereticus arm said...

It is not possible to send the planes to EMC for this reason?

Anonymous said...

Read the aviation specialty press and ignore the general press; they are idiots know not of what they write. Another example: The apparently missing MH370 or whatever the number. AP, NYT and others are reporting junk, perhaps just to full the page. Stick with industry-specific sources

Pete Templin said...

Ereticus Arm, it's not a question of whether it's possible to send the planes to EMC. Aside from the obvious costs to procure all of the materials, components, and modules to build the plane, Boeing budgets a certain number of work hours to assemble and test the plane. Those work hours fit into the master plan of delivering 10 planes per month: how many flightline stalls, how many wrenches, how many staff, etc. Handling the disassembly/replacement/reassembly of this issue is NOT in that budget/plan.

Further, Boeing has forecasted their sales numbers and incorporated those figures into their financial estimates, from which analysts have speculated (lied?) and investors have invested (gambled). Disrupting the line to service ~80 wings may delay deliveries, which can impact sales figures and cause disruption to stock pricing, etc. It can also cause planes to receive their planes behind schedule. I'd be especially wary of LN 146, 169, and 181, which I believe are the three initial production 787-9s heading to customers.

1coolguy1 said...

I would imagine Mitsubishi has sent techs to Everett and SC to make repairs together with Boeing techs.

As to the repair of these wings, since the repair is internal it will be interesting to see whether Boeing removes the wings for the repair or has to cut a section for access.
Uresh - do you have any info on this?

Uresh said...

Nope, I don't.

James Graham said...

We have discussed some weeks before that aircraft were routing to the EMC. Uresh even did a spreadsheet on it. Now we know why.

Andrew Boydston said...

The rushing of technology forward as an efficiency production step is a hole in the original due diligence as found in research and delvelopment. Questions on the table. How involved was Boeing during new applications on wing design or any other area area of the 787 previously resolved. It is disturbing to think that a new wing process or fastneer is developed without the same level of testing during the initial phase of wing production. Wing cracks should not have happened without appropriate testing of a new fasastner process by both Boeing and its supplier!

1coolguy1 said...

Interesting that Boeing apparently does not have its' own QC staff at these outsourced facilities.

I cannot believe this "change of procedure" was approved by either Boeing or Mitsubishi - sounds like employees took a short cut, as difficult as that is to believe.

PS: Thanks Uresh for changing the captcha to all numbers!!!