FAA Is Taking Advice It Earlier Rejected to Prevent Jets Missing
Runways
The U.S. Federal Aviation
Administration is implementing recommendations it rejected six
years ago that could have prevented pilots from nearly landing last month on a taxiway crowded
with jetliners awaiting takeoff in San Francisco.
The National Transportation Safety Board in 2011 recommended a
software upgrade to ground radar systems that would warn when a plane is landing
in the wrong place. But the FAA dismissed the recommendation, declining to even
study whether it was feasible, according to government records.
In an announcement issued since the San Francisco near-collision, the
FAA says it has begun over the past year doing what the safety board recommended
and testing could begin in a few months.
"We believe recent technological advances may now enable us to modify
our ground surveillance systems to detect aircraft that are lined up to land on
taxiways," the agency said Friday in an emailed statement.
Air Canada Flight 759 was approaching
the San Francisco International Airport just before midnight on July 7. Instead
of heading for the runway, pilots lined up about 500 feet to the right, aiming
for a parallel stretch of pavement where four planes were preparing for takeoff,
according to the NTSB. The tails of the first two planes on the ground were
about 56 feet high, just three feet below the landing plane's lowest altitude,
according to the safety board.
"Where's this guy going?" a pilot in a United Airlines plane that was at the head of
the line said in a radio call to the airport tower. The air-traffic controller
didn't warn the Air Canada pilots until after the cockpit crew had already
aborted the landing.
The potential risks of such a collision have been highlighted by
several similar instances in the past, including when actor Harrison Ford landed
a small plane on a taxiway in February at John Wayne Airport in
California.
The NTSB examined the issue in 2009 after a Delta Air Lines Inc. plane touched down on a
taxiway in Atlanta. No one was hurt because there were no other aircraft on the
taxiway at the time. The safety board concluded the crew's abilities were
degraded by fatigue after an all-night flight.
As part of that investigation, the NTSB found that an existing radar
system at major airports could be adapted to warn controllers if a landing plane
was headed to a taxiway instead of a runway. This was critical, according to
NTSB, because controllers stationed in airport towers often can't tell whether
an arriving plane is properly lined up for a runway.
Warning Opportunity
Investigators contacted what is now Saab
Sensis Corp., a division of Sweden-based Saab AB, to see if its system that tracks
planes on the ground would help. Officials at Sensis concluded the technology,
known as ASDE-X, could be programmed to detect a potential errant landing as far
as 0.75 miles from the airport at Atlanta, according to a March 2, 2011,
recommendation letter by NTSB.
"Such a warning would afford air traffic controllers the opportunity
to assess the situation and provide instructions to a flight crew that would
prevent a taxiway landing or potential collision with aircraft or vehicles that
may be on the taxiway," NTSB wrote.
The safety board, which investigates accidents but has no regulatory
authority, called on FAA to conduct a broader feasibility study and to upgrade
the warning system where possible.
Randolph Babbitt, the FAA's administrator at the time, responded
later that year that the ASDE-X system wasn't up to the task, according to NTSB
records of correspondence in the case. ASDE-X's primary job is to warn
controllers when there's a risk of a plane colliding with another aircraft or
vehicle on a runway. Adding a taxiway warning would degrade the system's primary
mission of preventing runway collisions, Babbitt wrote.
"Simply concluding that the performance tradeoffs would outweigh the
safety benefits of providing the recommended capabilities without performing the
review ... does not constitute an acceptable response to these recommendations,"
the NTSB wrote in response.
As part of its formal system of tracking recommendations, the NTSB
classified it as "closed -- unacceptable action."
A more recent taxiway landing, this one involving an Alaska Air plane in Seattle in 2015, helped
prompt the agency to refocus on trying to develop a technological solution,
according to the FAA. No other planes were on the taxiway and there were no
injuries.
The upgrade was also made possible by recent software improvements in
how the ASDE-X system tracked arrivals, the agency said.
"The FAA since last year has been working to modify the systems so
they will also capture aircraft that are lined up for taxiways," the agency said
in an emailed statement. "The agency expects to begin testing some modified
systems in a few months."
Read more: http://www.dailymail.co.uk/news/article-4755218/New-photos-close-jets-came-crash-SF-airport.html#ixzz4p91hqhMb
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New photos show just how close Air Canada plane came to hitting other aircraft in San Francisco as it's revealed there is a 'BLIND SPOT' in its radar system
- Air Canada Flight 759 almost crashed into four aircraft at San Francisco International on July 7 after pilots got runway mixed up with taxiway
- New flight data shows jet came within just a few feet of hitting waiting planes
- Aircraft also disappeared off key radar systems supposed to avoid a collision
- Controllers only called off landing after jet had passed over two waiting planes, and after pilots had started to pull up 'because something didn't feel right'
- The 'blind spot' means the wayward flight was not detected for 12 seconds
Federal investigators have found a 'blind spot' in San Francisco's airport radar that prevented air traffic controllers from spotting a wayward Air Canada flight.
The NTSB released the worrying information a month after the Air Canada plane almost crashed into four waiting jets with hundreds of passengers on board on the runway of the Bay Area transport hub.
Findings released on Wednesday show the aircraft came much closer to disaster than previously thought.
The 'blind spot' may have stopped a computer from alerting air traffic controllers of a wayward plane for 12 seconds.
The Airport Surface Surveillance Capability (ASSC) system — which monitors incoming aircraft to ensure they are safely landing at SFO and 34 other airports across the country — is designed to sound a warning from a loudspeaker in the tower if an airplane is off course.
Air Canada Flight 759 almost caused one of the worst disasters in aviation history when it tried to land on a taxiway at San Francisco Airport where four planes were stopped (aerial view above, CCTV pictured bottom)
A new report says the Air Canada pilots were told not to land on runway 28L, which was closed, and to land on 28R instead (top). But they wrongly lined themselves up with taxiway C, where the four planes were waiting. As Air Canada came into land off course (bottom) pilots on the ground radioed Air Traffic Control saying: 'Where's this guy going?'
No alarm sounded July 7 when Air Canada Flight 759 mistook a crowded taxiway for an approved runway, nearly triggering one of the worst aviation disasters ever. The plane also avoided SFO’s Airport Surface Detection Equipment, according to new NTSB findings.
Air Canada Flight 759 was just 59ft above the ground on the night of July 7 before the pilots managed to pull up, less than 3ft above the tail fins of the planes waiting on the taxiway below.
Had the aircraft collided it would have caused one of the worst air disasters in history, likely costing hundreds of lives.
Read more: http://www.dailymail.co.uk/news/article-4755218/New-photos-close-jets-came-crash-SF-airport.html#ixzz4p91hqhMb
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