"We have had a number of experts look at this, and all of them say the structure is too light and allows it to bend and change its airfoil," said Arthur Wolk, whose Center City-based firm has won more than $1 billion in jury verdicts and settlements in aviation lawsuits. "It is my view that, given the history of these airplanes, the stabilator needs to go. If you have an engineering flaw, it will always rear its ugly head until you fix it."