Citing the extended work stoppage of the 57-day machinists' strike, Boeing says the 787 will not accomplish its goal of flying by the end of the fourth quarter of 2008.

Boeing adds that it will not set a new target date for first flight or first delivery while a full assessment of the programme's post-strike status remains ongoing.

Included in the assessment is a costly manufacturing error. Boeing acknowledges a need to reinstall slightly less than 3% of all fasteners throughout its production system.

Boeing's last schedule called for delivering the first 787 to launch customers All Nippon Airways in the third quarter of 2009.

This latest delay is the fifth slip for the first flight of Dreamliner One since September 2007, and suggests the event could occur almost two years after the original schedule target.

The fastener fix covers about about two dozen shipsets spread all over the world, which include the four flight test and two ground test aircraft currently in Everett, Washington.

"The issue is with installation of the fasteners, not the fasteners themselves,'' Boeing says.

As a result, the company is conducting a root cause analysis to determine the exact source of the problem. A preliminary examination indicates that unclear specifications for the fasteners resulted in misinterpretations at the time of installation.

The airframer is reworking those specifications and supplying the workforce in both Everett and the partner base with additional training to ensure this problem does not repeat itself.

Boeing is "not aware" of any other installation issues on the aircraft that would require a reassessment.

The company emphasizes that the 787 programme's quality control system caught this problem before any non-conforming parts were allowed to fly.

Boeing says the problem was discovered two weeks ago during a scheduled inspection of the airframe undergoing static testing in Building 40-23 at the Everett facility. As a result of the findings on the static airframe, Boeing began randomly sampling fasteners across the other flight test aircraft and found the problem to be widespread.

Of those 3% of fasteners, many are either too short or too long. This leads to small gaps beneath the head of the fastener, a design non-conformance requiring reinstallation.

Although the exact number of fasteners requiring reinstallation was not disclosed, Boeing has said that the 787 uses 80% fewer fasteners than an aluminium aircraft of equivalent size. The 767, slightly smaller than the 787, has roughly 1.8 million fasteners per aircraft. This estimate could place the number of required fastener reinstallations in the thousands across the programme.

Boeing emphasizes that no improperly-installed fasteners will travel from supplier partners to Everett, minimizing the additional traveled work.

Source: Air Transport Intelligence news