787 programme as it moves to redesign this critical structural component.

Flight has learnt that testing revealed that the 787’s composite centre wing spars, that hold the structure of the wingbox together, buckle more easily than metal spars. The composite spars were originally designed within non-buckle tolerances, but as weight crept up subsequent design iterations saw their width reduced.

Sources inside the programme say the buckling was discovered after the wing boxes were manufactured, and as it is too late to increase the thickness of the spars on six airframes already under construction (four flight-test aircraft and two test specimens), they will be modified with stiffeners.

These have already arrived at the final assembly line at the Everett, Washington, factory and will negate the weight savings sought by reducing their width originally. At some point a redesigned wingbox will be introduced.

<BR

This entry was posted on Tuesday, March 25th, 2008 at 3:00 pm and is filed under Uncategorized. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.