The temporary grounding of the Boeing 787 flight test airplanes to deal with the latest assembly issues is not a safety-of-flight issue and was not sought by the flight test crews, says Scott Fancher, program manager.
The Seattle Times reported the cessation of flight tests yesterday. Boeing disputes the term “grounded” and says the flights are discontinued until inspections and repairs are completed.
In a telephone press conference this morning, Fancher says the problem with shims and fasteners in the horizontal tails assembled by Italy’s Alenia stem from improper gaps surrounding the shims and too much torque on the fasteners.
There are 25 tailplanes that require inspections, not all of which are on airplanes. Fancher refused to specify if any of the five operational test airplanes have been found with defective workmanship. The sixth airplane is still in the Everett hangar and is scheduled to fly in July.
It takes a day per plane to inspect the tailplane and up to eight days to make repairs, if needed. Two test airplanes were in flying mode when the decision came down to suspend flight testing. The other three were in planned “lay-ups,” which means scheduled ground testing and maintenance. These airplanes now are undergoing concurrent tailplane inspections.
Test airplane #2 was scheduled to fly today but is grounded pending inspection and possible repairs. Test airplane 3, the other currently flying airplane, is also grounded for inspection and potential repair.
“We made the decision to prioritize the inspections before flying airplanes 2 and 3,” Fancher said. “This is not a design issue. This is a straight-forward workmanship issue. As we went through the day we made the prudent decision to hold off flying 2 and 3, which are ones flying now.”
The shim issue emerged last week and flight restrictions were imposed over the weekend. Fancher said the flight test crews were informed but the decision to terminate flight testing pending inspections and repairs was made by the engineers.
“Gaps were larger than design allows. Put in TOL (temporary operating limitation),” Fancher said. “During the day yesterday began getting information about the torque [of the fasteners], and we wanted time to understand it. I’m not telling you it was a safety of flight issue. We reacted conservatively. The process here works. In this situation, this was a build quality and an engineering issue.”
There are two shims and 24 fasteners, equally divided on both sides.
Fancher said despite any repairs and interruption in the flight test schedule, first delivery to All Nippon Airways is still scheduled by the end of the year.
Fancher also announced that there will another re-sequencing of the delivery flow through the global production system, similar to that which occurred in May for 24 days but on a different scale and scope. The May re-sequencing involved major fuselage components. This re-sequencing involving other systems.
The result will be that some customers in 2010 and 2011 may see deliveries delayed but the total number of airplanes delivered in the year will remain as projected.