Something to make one pause before boarding Airbus' new super jumbo A380 is how they saved weight. Fully 40% of the wingbox which ties the wing with the fuselage is made of carbon-fibre composite. It keeps the wingbox strong while saving weight. Less weight means more cargo and passengers carried with greater efficiency. That is the good part. The bad news is when composites delaminate without any external signs.
Ask the passengers of Air Transat Flight 961 aboard an Airbus A310 in 2005. Their composite rudder parted company with the rest of the airplane at 35,000ft. Thankfully the crew was able to safely land the plane sans rudder. Or when FedEx did some ground tests on one of their A300s in 2002 because a pilot reported uncommanded rudder movements. The rudder actuators tore through their mount points in the composite rudder.
Airbus insists that visual inspection of composite parts is all that is needed to detect any problems. Others disagree and insist on ultrasound being used to detect delaminations invisible to the naked eye. Prof. Williams of MIT thinks the cycles between the frigid temperatures of high altitude flying and that of sea-level causes moisture trapped between layers to go through freeze/thaw cycles creating gaps that are invisible to a visual inspection. It seems ultrasound is taking hold as the inspection method, but what happens when the forward bulkhead of an A380 wingbox is detected as delaminating? Scrap the whole plane or take it all apart to fix it?
And Airbus has made 40% of the A380 wingbox out of composites. Something to think on when selecting a trans-oceanic flight.