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Wingman: Safety Technology; What Else Is Out There?
In a
nearby story, the FAA's top safety official, Nicholas A. Sabatini,
reflected on the extraordinary safety record of modern commercial aviation
and noted the contribution made by technology. Without any way
of diminishing Mr. Sabatini's important and appropriate observations, Wingman
would offer some examples of other technologies that are important not only
to commercial aviation safety, but to non-commercial and some military
aviation as well.
First let's review what
causes most airline accidents, using the latest available annual summary
provided by Boeing in its "Statistical Summary of Commercial Jet Airplane
Accidents Worldwide Operations, May 2005." (See first graph below.)
Keeping in mind that
these data span the period of 1987 through 2004,
the 56 accidents caused primarily by CFIT might be somewhat misleading,
because as Mr. Sabatini pointed out, new technology such as TAWS (terrain
awareness and warning system), or EGPWS (enhanced ground proximity warning
system) as it's more commonly called in the U.S., have dramatically affected
this potential safety hazard in a positive way in recent years.
Nevertheless, the graph
indicates that pilot errors related to aircraft control and awareness of
position continues to be major factors related to fatal accidents, along with
power-plant and other aircraft system failures.

Source: Boeing “Statistical Summary of
Commercial Jet Airplane Accidents Worldwide Operations, May 2005
When the accident causes
are aggregated still further as represented in the chart below, it can be
seen that pilot situational awareness of the aircraft's position relative to
the runway and other surroundings, as well as proper control usage, is still
a major area for improvement. System failures are an important second place
to put more attention. Together these two categories have caused more than
nine out of ten fatal accidents between 1987 and 2004.

Based on Boeing
Statistical Summary of Commercial Jet Airplane Accidents, May 2005
Happily, there are a
number of new technologies that should be able to ameliorate all of
these causes - and over time, substantially reduce those related to
so-called pilot error. Some of these technologies are still expensive,
and aren't widely available on all aircraft types. And a few have
unresolved certification issues that would increase their operational
usefulness and economic attractiveness. But if history is a valid guide,
their capabilities will likely expand over time, and their costs will
enviably go down.
Each of the
technologies listed below can be related - often very directly - to the
causes depicted in these charts:
-
Modern HUDs
(head-up displays) that give pilots highly intuitive approach and
flare guidance, speed control and trend, and angle-of-attack,
unusual attitude and windshear escape if needed. These tools likely
could have prevented many accidents related to poorly executed
approaches and landings, as well as takeoffs and some inflight
upsets.
-
GPS position
navigation, which when augmented by external or onboard systems and
supplemented by new procedures, such as RNAV (area navigation) and
RNP (required navigation performance), gives pilots new approach
capabilities, including vertical guidance, to many more runways.
-
Honeywell's RAAS
(runway awareness and advisory system) uses GPS position information
and EGPWS (enhanced ground proximity warning system) databases that
alert the crew if they should attempt to takeoff or land on a wrong
runway, prevent an unauthorized taxiway takeoff, and provide
distance remaining callouts, among other things.
-
The graphical
depiction of weather delivered via datalink in real time that
clearly shows the pilot, his position relative to metrological
hazards, such as thunderstorms, with a 360 degree field of view.
-
Datalink that
makes communications more reliable and accurate, and virtually
anywhere in the world with satellites. (The single most deadly
accident in aviation history, the runway collision of two B-747s at
Tenerife, begin with a "stepped on" voice transmission.)
This list is more
representative than complete, and certainly leaves somethings out. Furthermore, the list could be organized and combined in a manner that
would show the significant synergism that exists between many of these
technologies that makes them even more valuable for purposes that serve
both safety and operational effectiveness.
Wish List
This list is
impressive and very encouraging in Wingman's view. Yet there is even
more that might be possible, and even quite feasible. Here are some
safety systems that Wingman wished we had, but aren't yet developed or
haven't appeared on the scene. (If they are,
please let us know):
-
A takeoff performance monitoring
system. Such a system would alert or warn the pilot that
the aircraft isn't accelerating properly on takeoff. Simply put,
the
system would use an aircraft's inertial sensors to compare its actual
acceleration rate with what is required based on inputted
environmental factors and runway information from a database. Alerting and warnings should occur as early as possible in the
takeoff roll while the aircraft is at a low energy state.
The system
shouldn't try to be too smart in determining either the cause of
lacking performance or what the pilot should do; it should only
alert and warn. The pilot's action should be procedural as it is
with TAWS: abort the takeoff as quickly as possible, when the ground
speed is low.
The system would
be able to detect inadequate performance from many causes: too much
weight, too little thrust, runway clutter, and even a dragging
brake.
-
A landing performance monitoring
system. This system would alert or warn the pilot that
the aircraft has too much kinetic energy (ground speed) or potential
energy (height) to safely continue, relative to the anticipated
touchdown point and runway remaining. Many air transports and
business jets already have the necessary sensors (GPS, inertial, and
maybe radio altimeter) that could be correlated to a runway database
to make the needed calculations.
-
A degraded wing-lift detection
system. While such a system may be considerably more
challenging - both in terms of capability and economics - its
successful development might someday save many lives. In theory it
would monitor the elements that make up an airfoil's lift potential
early enough to warn the pilot to discontinue a takeoff prior to
liftoff, if it is deemed inadequate.
Perhaps the most
obvious benefit of such a system would be its ability to prevent
accidents that have resulted from wing ice or frost contamination, but it
might usefully work in conjunction with other sensors that detect
improper flap configuration, over loading, or even improper balance. 05-17-2006.
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