Stretched thin on engineers by the 787 production crisis, overwhelmed by unexpected design requirements and caught out by a supposedly mature supply chain, Boeing marked the 747-8 family's third anniversary on 14 November by announcing a stunning schedule delay.
Boeing shifted the delivery date for the 747-8 Freighter to Cargolux from late 2009 to the third quarter of 2010. First delivery of the 747-8 Intercontinental, a passenger variant struggling to attract orders, dropped from late 2010 to the second quarter of 2011.
Boeing's marketing material has already trimmed back performance comparisons between the 747-8F and the Airbus A380.
Compared with a fact sheet dated 2005, Boeing's current online fact sheet has reduced the 747-8F's fuel burn advantage to the A380 from 14% to 11%. Boeing has also trimmed its projected advantage on fuel burn per ton from 25% to 24% and on ton mile costs from 23% to 22%.
With the 787-8 already 18 months behind schedule and facing new delays, the 747-8 family's setback may seem trivial. However, as a stretched and rewinged extension of the 45-year-old 747 family, developing the 747-8 was not expected to face nearly as many challenges as the all-new 787 production system.
The news also marred an otherwise rare hopeful moment for Boeing Commercial Airplanes this year.
On the same day Boeing disclosed the six- to nine-month delay for the 747-8F, the airframer signed a tentative agreement with the Society of Professional Engineering Employees in Aerospace, relieving concerns about a looming strike by 21,000 workers.
The news also came only five days after Boeing's 27,000 machinists returned from a costly, two-month strike.
The absence of Boeing's production workforce in September and October is partly to blame for the 747-8 delay. However, Boeing acknowledges the work stoppage by the International Association of Machinists and Aerospace Workers played only a bit-part in the story.
Indeed, Boeing executives now describe coming to grips with the scale of the 747-8's problems in August - shortly after the first 747-8F started final assembly and just before the IAM strike began on 6 September.
The IAM strike began "shortly after we initiated a review of the [747-8] program," Boeing vice-president Randy Tinseth wrote on his blog on 14 November.
Boeing launched the review to find out how far the programme had fallen behind. Months earlier, Boeing had designated August as a critical month in the 747-8F's development and, outwardly, events seemed in order. As scheduled, the first airframe started final assembly and a far-flung team of engineers managed to release 90% of the engineering drawings for the aircraft.
In achieving both milestone events, however, Boeing was suddenly forced to come to grips with supply-chain breakdowns that until then were recognised but not understood, says Michael Teal, the 747's chief engineer: "After we got to the 90% release milestone of engineering drawings in early third quarter and started to begin production we realised we weren't getting the parts in on time. A lot of [the issues] came home at that point."
To be sure, hints of internal issues had appeared before, even to outsiders. Boeing reassigned the original programme manager, Dan Mooney, last September, amid a broader upheaval caused by problems with the 787-8.
The management shakeup was quickly followed by a schedule reshuffling. Boeing originally planned to assemble 747-8s and the 747-400s concurrently on the same line.
This ambitious plan would save months on the schedule, but require machinists and the supply chain to produce the older model at the same time as they learned how to build the new aircraft. Complicating concerns about the concurrency issue, Boeing also faced an unexpected problem with the 747-8 wing's new supercritical airfoil design, Teal says.
By September 2007, the concurrent production strategy was deemed too risky, but executives refused to the delay the entry-into-service date. Instead, Boeing decided to shift the schedule risk from the production line to the flight-test phase.
The airframer moved back assembly of the first 747-8F to August, allowing a clean break between the 747-400 and the new derivative. Boeing also postponed the roll-out date from late 2008 to February 2009.
At the same time, Boeing decided to compress the flight-test schedule, allowing the first 747-8F to be delivered on time despite the production delay.
Unfortunately, that left a short flight-test period to certificate the airworthiness of an aircraft stretched by 5.6m (18ft), which also features an all-new advanced airfoil, all-new General Electric GEnx-2B67 engines and new onboard systems derived from the 787.
"When we moved the line numbers last year, we didn't change the [entry into service] date," Teal says. "That caused us to put a higher-risk flight-test programme in place. We're adding that time back in because we haven't found a credible way to reduce risk in the flight-test phase."
The flight-test phase is now allotted between seven and nine months to complete, Teal says. By comparison, Boeing completed the flight-test programme for the 777-200LR, a perhaps less ambitious derivative programme, in about 10 months in 2005.
Source: Flight International
