An American Airlines plane that
careened off a slick Jamaican runway last year has prompted crash investigators
to reassess how well some jetliner braking systems perform on various runway
surfaces in rainy conditions, people familiar with the details say.
American Flight 331 was en route
from Miami to Kingston in stormy weather when it landed nearly halfway down the
runway on 22 December. The pilots used maximum braking power but the Boeing 737 still slid off the end
of the strip, ending up with a collapsed landing gear and the fuselage cracked
in two places.
The crash, according to these
people, has led the National Transportation Safety Board investigators to
challenge longstanding airline practices and technical assumptions regarding
braking capabilities on wet runways. By those criteria, the advanced Boeing
737-800 should have been able to stop safely on the strip.
Investigators don’t believe there
was a significant pool of water on the runway, though the crew was battling a
stiff tail wind as well as some malfunctioning runway and approach lights,
these people said. The crash, which didn’t result in any fatalities, left
several of the 154 people aboard hospitalized.
Preliminary information gathered by
investigators indicates the two-engine jet started to slow down, but then
failed to decelerate as quickly as it should have and actually picked up speed
slightly for a brief period. Even after maximum manual braking was applied,
these people said, the deceleration rate never reached levels projected by
earlier flight tests and engineering calculations for the apparent runway conditions
Safety board investigators are
inclined toward drafting recommendations to reassess, and in some cases
tighten, current safety margins for landing on wet runways, according to people
familiar with the continuing investigation. Any final action will require
approval by the board’s members, and the preliminary conclusions could change.