1.   During the first set of hearings in January, investigators determined that a rudder deflection caused the aircraft to roll.

2.   Investigators strongly suspect that a full rudder deflection is the only thing that could have triggered such a violent and deadly roll.

3.   It would have prevented the full rudder deflection that occurred in the USAir crash.

4.   The hydraulic pressure reducer limits the amount of rudder deflection that can occur.