First activation of the Boeing 787s electrical system is likely to slip again, forcing first flight and entry into service further back into 2009.
Power-on could occur as early as mid-April according to senior Boeing representatives, yet, internal assessments of the pace of work on Dreamliner One suggest that the milestone could slip to June with slightly more than half of the 600 jobs, or tasks, remaining before power-on.
At least one 787 customer, who spoke with FlightBlogger on the condition of anonymity, has been told by the manufacturer that power-on will likely slip to June.
Boeing was unreachable for comment on the entirety of this report, however, sources familiar with the situation say that the airframer has not formally notified any customers to changes in the power-on schedule.
Paperwork and Design Changes Slowing Assembly
According to program sources, the slow pace of work in recent months can largely be attributed to what are known as rejection tags. Those tags occur when a discrepancy exists between the design and the product. For example, during the normal manufacturing process, holes are drilled to install fasteners. Occasionally, those holes have to be drilled a second time if there is an issue with the first hole. As a result, the hole is considered to be “non-conforming” requiring a larger diameter fastener and must be checked through a quality certification process.
One foundational tenet of the 787 program, according to program sources working with the aircraft, was the idea of a “super-mechanic” who held all the necessary certifications to self check work to appropriate airworthiness standards.
According to sources across the program, over the past year of assembly the self-certification process has become an impediment to progress rather than an enabler of efficiency.
As a result, the 787 program has begun to shift from a system of self-certifying manufacturing staff to a more traditional system of quality assurance similar to Boeing’s legacy programs. The revised system is first being implemented for out-of-sequence traveled work and is expected to be expanded to the entire final assembly process.
The revised system is a “positive step,” says one person working with the aircraft.
By using its traditional quality assurance system, Boeing is able to better control and group the number of rejection tags to reduce paperwork and solution time. For example, under the original system, four non-conforming holes in the same area of the aircraft were filed as four individual issues rather than just one. The new system would streamline the process by grouping these rejection tags together, cutting paperwork, in this example, by 75%.
At another level, minor, yet time consuming, design changes are occupying significant resources.
Often, “Parts are not delivered and substituted with different parts or mechanics make mistakes. Sometimes design error makes it impossible to build as designed,” said one source familiar with the situation.
Each redesign has to go through an extensive process that slows the path to power-on.
Boeing released a statement on the subject as this analysis was going through final revisions:
“It is normal during the development of a new airplane to discover the need for design enhancements. We are working with our partners to address the need for design changes in some areas. While these changes are not good for final assembly because they are dealing with traveled work at this time, the design changes are not the sole pacing item.”
Read the complete post at http://www.flightglobal.com/blogs/flightblogger/2008/03/flightblogger-analysis-787-pow.html
Wed, Mar 19 2008 8:25 PM
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