Each 747-8 that rolls out of the Everett, Wash., factory has been completed only after mechanics have hand-drilled thousands of holes during production. In five of the major 747-8 fuselage assembly areas alone, mechanics drill more than 17,000 circumferential join and lap-join holes by hand — going through nearly 700 drill bits in the process.
That’s changing, however, with the first installment of a major investment in 747 manufacturing improvements aimed at ensuring the highest levels of quality and improving employee safety. The Section 44 (mid-body) major join area was the first of five assembly shops on the 747 production line to receive new Flex Track automated drilling systems. A total of 14 are planned for the 747-8 program. Four have been implemented as part of the first phase, and the 10 remaining will be integrated over the course of the next one and a half years.
“This is about getting the right tools for our mechanics,” said Erik Pham, senior manager of Build Integration for the 747 program. “Once fully implemented, we will have automated the drilling of more than 17,000 holes on the 747, but more importantly, we expect to see a 12 percent reduction in on-the-job injuries for the implemented areas.”
While the drilling process is fundamental for building airplanes, it has remained largely unchanged since the earliest days of the aviation industry and requires high levels of repetitive motion. When drilling is performed manually, a mechanic uses a drill to create a hole through overlapping pieces of structure, followed by a countersink operation and installation of a fastener. The manual drilling process also generates a high volume of metal shavings, which can become FOD (foreign object debris).
In contrast, Flex Track is programmed to drill the hole, countersink and contain the metal shavings, eliminating the repetitive motion that causes physical stress to people.
“Drilling 600 hundred holes by hand [in one section], and then another motion to re-countersink all those holes, that really takes a wear and tear on your body,” said 747 mechanic Ryan Rice. “Setting up the Flex Track and having it drill that for you — it is really going to save my body.”
Instead of hand-drilling holes, stopping every 30-40 holes to replace a drill bit, Rice now sets up the Flex Track machine and runs the software to operate it. Each machine's bit can drill 10,000 holes before being replaced.
“We still need mechanics with the Flex Track machine. It has to be set up, prepared, operated and removed,” said Pham. “Flex Track will change the nature of the work, but we are training our current mechanics to use these new tools and don’t anticipate a change in employment levels as the result of this new technology."
Flex Track has already been implemented in key places on the 767, 777 and 787 programs.
“We know that this technology works and that the benefits are real,” Pham said. “In addition to the improvement in safety, Flex Track brings a nearly 50 percent improvement in first-pass quality and a meaningful reduction of FOD. Once fully implemented, nearly 30 pounds (14 kilograms) of FOD will be automatically collected with Flex Track machines on each airplane.”
The technology is expected to be “transformational” for the 747 program as it strives to increase efficiencies and improve first-pass quality, program leaders said.
“The 747 program is a crucial part of the Boeing commercial product line up,” said Bruce Dickinson, vice president and general manager of the 747 program. “We have to keep finding ways to improve safety and quality, and we are making significant investments to ensure our success, and this is certainly one of them.”