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Following tests by the US Federal Aviation Administration, Boeing is to
re-engineer part of the rudder control system for its 737 passenger jet. The
rudder’s hydraulic power control unit was modified last year after it was
implicated in the fatal crash of a USAir jet in 1994. The FAA found that the
control unit could jam the rudder hard left or right, sending the plane out of control
(¿ìè¶ÌÊÓƵ, 4 March, p 32).
But Jim Hall of the National
Transportation Safety Board says that further investigation has found “dozens of
single failures and jams and latent failures in…