Dealing with the latent issues created by last year's schedule reshuffling was only one of the causes for the recent delay announcement.
As the 787-8 production crisis came to light from September 2007 to March 2008, senior Boeing executives consistently maintained that the company had enough engineering resources to solve that problem as well as keep other development efforts, such as the 747-8, on track.
"There's obviously engineering resources that have shown up late on the -8, but we found ways to work around that by accessing engineers throughout the company and external resources," Boeing chairman and chief executive Jim McNerney said on 24 October 2007.
That statement has been contradicted by more recent remarks from Boeing executives.
For example, vice-president Randy Tinseth wrote on 14 November: "The [747-8] programme has also been affected by limited engineering resources within Boeing."
As the 787-8 kept commercial aircraft engineers busy longer than expected last year, Boeing assigned engineers from its military aircraft division to the 747-8F. The process of releasing engineering drawings for the 747-8I is only now getting started.
The company also signed deals with engineering firms in Asia, Europe and Russia and the USA to make up for the shortfall on the 747-8F.
But it did not take long for Boeing to realise that the distributed engineering strategy had partly backfired. It became a difficult chore for Boeing simply to keep track of all the work.
In April, Ross Bogue, Boeing's new vice-president and general manager for the 747-8 and Everett site leader, said the company would change its approach for the 747-8I variant. It would use as many external engineers, but they would be concentrated in a few key hubs rather scattered all over the globe, he said.
Driving demand for more engineering resources were persistent and self-perpetuating design changes caused by the new, super-efficient airfoil.
To meet Boeing's original performance targets for the 747-8, Boeing has had to move the centre of gravity on the airfoil from the aft section of the wing forward, but this has caused a variety of new problems.
"When we changed the wing airfoil and ultimately changed the centre of gravity, this fundamentally shifted how the whole aircraft balances loads", Michael Teal, the 747's chief engineer says. "As the loads shifted back on the wing the tail is the balancing load. So we changed more parts in the tail. But then the loads in the aftbody changed, so we have to change the aft body."
While the engineers struggled to make their sums add up, the 747-8 supply chain was left waiting to adjust tooling and place long-lead orders for new materials.
"We knew which suppliers were going to make what so getting that through is the same," Teal says. "It's just a matter of estimating the amount of time required to get all the change in their factories."
Source: Flight International
