The Wall Street Journal
By Rob Barry, Tom McGinty and Andy Pasztor
Updated Dec. 11, 2013 10:18 p.m. ET
Foreign
airline crews experienced problems approaching San Francisco
International Airport at a greater rate than U.S. pilots when the
airport's landing guidance system was impaired, a Wall Street Journal
analysis of government data found.
The findings, based on nearly
100,000 flights coming into the busy hub over six months, come as
federal investigators held their first public hearing Wednesday on the
crash last summer of an Asiana Airlines Co. jet in which three people
died and 180 were injured. The pilots' undue reliance on automated
flight systems has emerged as a key factor in that crash.
Asiana,
based in South Korea, had the highest rate during the system outage of
any carrier serving San Francisco for "go-arounds"—approaches broken off
at low altitude before touchdown—the Journal found.
In July, an
Asiana Boeing Co. 777, flying dangerously slow and low into San
Francisco, slammed its tail into a seawall in front of its intended
runway. Investigators of the crash are focusing on pilot confusion about
automated thrust settings, coupled with the cockpit crew's failure to
properly monitor the jetliner's speed and trajectory during the visual
approach in good weather.
At its public hearing, the National
Transportation Safety Board revealed Wednesday that the commander of the
Asiana jet failed to respond to as many as four verbal warnings from a
co-pilot that the aircraft was descending too quickly shortly before
impact. The pilot flying the approach told investigators afterward he
had been "very concerned" about executing the approach to San Francisco
without precise vertical guidance.
Asiana officials said
Wednesday that all company pilots flying into SFO had the required
training, experience and the confidence of management.
The
instrument landing system at San Francisco provides just such vertical
and horizontal guidance, giving pilots detailed visual cues on their
instrument panels if they veer from a safe trajectory. Otherwise, crews
would have to use their own eyes and judgment to line up with a
less-precise array of lights alongside the runway intended to help
pilots stay on the correct path.
Over a five-week stretch leading
up to the July 6 crash, a pivotal component of the system at SFO, as
the airport is known, was out of service on the two busiest runways
because of construction.
During the outage, foreign carriers
broke off landing approaches to go around and try again at a rate nearly
three times as high as their American counterparts, according to the
Journal's analysis. The Journal examined radar data for 95,436
approaches to San Francisco's runways 28L and 28R, and focused on
go-arounds initiated at altitudes of 1,000 feet or lower.
From
Jan. 1 through June 1, the point at which San Francisco's "glideslope"
equipment was taken out of service, non-U.S. carriers executed at least
20 go-arounds at or below 1,000 feet in 5,349 approaches to the two
runways, for a rate of 3.7 go-arounds per 1,000 flights. That is about
37% higher than the 2.7 per thousand for domestic carriers in the same
period.
Once the glideslope shut down, rates rose for both
domestic and foreign carriers, but the increase for non-U.S. airlines
was significantly larger.
Relying on visual approaches without
precise, ground-based guidance, foreign airlines racked up at least 17
go-arounds out of 1,534 approaches, a rate of 11.1 per 1,000 approaches.
By comparison, the rate for U.S. airlines during the same period was
4.3 per 1,000 approaches.
Four of the go-arounds by non-U.S.
carriers involved Asiana, including one executed 400 feet from the
ground just after midnight on the day before the crash. The other three
planes each descended to 200 feet before executing their go-arounds.
An
Asiana spokesman declined to confirm the total, saying "Asiana's policy
is that any pilot can call for a go-around, and can do so without
penalty."
Safety experts cite various reasons for the discrepancy
between U.S. and foreign airlines. Some say foreign crews have less
exposure to SFO's busy airspace; its closely spaced parallel runways;
and the tendency of controllers to boost airport capacity by often
maintaining minimum required spacing between planes. Others see some
foreign airlines playing down manual skills—particularly for pilots
flying widebody planes on long-haul routes—because automated controls
are more fuel-efficient than manual flying.
Pilots can perform
go-arounds for a variety of reasons, including congestion on the ground
or in the air, and a failure to properly align the plane with the runway
late in the approach. In some cases, the aborted landings are ordered
by air-traffic controllers; other times, pilots make the decision to try
again. According to the FAA, go-arounds "are routine, standardized
procedures, and can occur once a day or more at busy airports for
various reasons."
The spate of go-arounds by non-U.S. carriers
may be explored in testimony and documents slated to be released this
week as part of the NTSB's hearing.
"The statistics for
go-arounds are obviously a significant element" as investigators unravel
what happened and why the accident occurred, according to Robert
Francis, a former vice chairman of the safety board. "It's just the kind
of thing the NTSB certainly will be paying a lot of attention to."
Roughly
two weeks after the accident—with part of the ground-based precision
landing equipment still inoperative—the FAA took the unusual step of
publicly prodding pilots of foreign airlines to use satellite-based aids
or other systems as safeguards when landing at SFO.
Air-traffic
controllers also stopped clearing foreign carriers for simultaneous
visual approaches to closely spaced parallel runways, which can distract
pilots. The extra precautions, which didn't apply to U.S. carriers,
were lifted on Aug. 22, the day when SFO's glideslope equipment was put
back into service.
This week, an FAA spokeswoman said the special
procedures were prompted by "an increase in go-arounds at SFO by some
foreign carriers that were flying visual approaches," though she didn't
provide specifics.
The data analyzed by the Journal showed the
flight tracks of all aircraft that approached SFO during the period,
providing each plane's latitude, longitude and altitude approximately
every five seconds. The data didn't include reasons for the any of the
maneuvers those planes made.
Source: http://online.wsj.com
NTSB Identification: DCA13MA120
Scheduled 14 CFR Part 129: Foreign operation of Asiana Airlines
Accident occurred Saturday, July 06, 2013 in San Francisco, CA
Aircraft: BOEING 777-200ER, registration: HL7742
Injuries: 3 Fatal.
This
is preliminary information, subject to change, and may contain errors.
Any errors in this report will be corrected when the final report has
been completed. NTSB investigators traveled in support of this
investigation and used data obtained from various sources to prepare
this aircraft accident report.
On July 6, 2013, about 1128
pacific daylight time, Asiana Airlines flight 214, a Boeing 777-200ER,
registration HL7742, impacted the sea wall and subsequently the runway
during landing on runway 28L at San Francisco International Airport
(SFO), San Francisco, California. Of the 4 flight crewmembers, 12 flight
attendants, and 291 passengers, about 182 were transported to the
hospital with injuries and 3 passengers were fatally injured. The
airplane was destroyed by impact forces and postcrash fire. The
regularly scheduled passenger flight was operating under the provisions
of 14 Code of Federal Regulations Part 129 between Incheon International
Airport, Seoul, South Korea, and SFO. Visual meteorological conditions
prevailed at the time of the accident.
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