49 Reported Cases Of Dark Displays In Recent Years
Few would argue that so-called "glass cockpits" are a major
leap forward in cockpit management and crew safety... until those
panels go dark in-flight, which the National Transportation Safety
Board says has happened at least 49 times in recent years onboard
several Airbus airliners.
On Wednesday, the NTSB issued five recommendations to address
concerns about cockpit displays going inop on Airbus A319 and A320
narrowbodies. Of the 49 incidents reported to the Board, seven
involved all six cockpit displays going blank at once... something
safety experts once thought was all-but impossible.
Sixteen planes lost five of the six cockpit displays. In
addition to flight instruments and engine monitoring systems, loss
of the avionics displays also resulted in the loss of comm systems,
transponders, and traffic advisory systems.
In January of this year, a United A320 had to make a hasty
return to Newark Liberty, when the captain's primary flight display
(PFD) and navigational display (ND), along with the upper
electronic centralized aircraft monitoring (ECAM) display, went
blank on takeoff. The plane was able to make a safe emergency
landing, helped greatly by the fact conditions were VMC.
The NTSB notes the first officer's ND remained functional, as
did the lower ECAM display. The first officer also reported that
the attitude information on his PFD was initially not usable, but
that the information appeared to be reliable later in the
flight.
Those circumstances were similar to those experienced onboard a
British Airways A319 three years before, which suffered failures to
five of six cockpit displays while cruising at FL200 from London to
Budapest. Most of the screens returned within 90 seconds.
British investigators have already issued safety recommendations
related to the problem, and Airbus issued a safety bulletin in May
2007 recommending new wiring fixes and increased crew training on
how to handle electrical systems failures. But those fixes aren't
mandatory, and the NTSB says they should be.
Included in the six recommendations from the NTSB are calls for
a backup power supply to be added to the standby attitude
indicator, and the automatic reconfiguration of the AC essential
bus power supply in the event that the AC 1 electrical bus fails.
The NTSB also wants greater crew training, and additional simulator
time for pilots to learn how to handle such failures.
FMI: Read The NTSB Recommendtions Here And
Here
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