Sorry, that site requires registration, but notwithstanding that, I fail to see how the loss of what sounds like a spoiler panel makes the MD11 a biplane? If it was sucked into one of the engines, that would do it, but it doesn't sound too serious (although those on the ground would probably think differently).
Also, if it was a panel on the upper wing surface, it would have been whipped off so quickly it wouldn't have had time to hit anything on the lower surface.
They'll just have to courier the part back to Memphis . . . possibly on UPS!
