USA, Boeing 737, the worldwide most used jetliner, of which the Seattle industry delivered about 3800 units since it took service in 1967, will have to change the rudder, as FAA ordered. Investigating commissions of two air crashes, USAir flight 427 in 1994, in which 132 people have been killed, and United flight 585 in 1991, in which died 25 people, reported rudder malfunctions were blamed for both...