July 08--The Federal Aviation Administration is investigating an incident 10 miles northeast of Bush Intercontinental Airport where two airplanes narrowly avoided each other midair, the second such close call in Houston's skies within two months.
The planes came within 200 feet vertically and half a mile horizontally of each other Thursday after a Singapore Airlines pilot continued to climb beyond 4,000 feet, intersecting with the path of a Delta Air Lines jet, according to the FAA and audio from the air traffic tower. A controller alerted the pilots so they could change paths.
The incident follows a May incident, under investigation by the FAA and the National Transportation Safety Board, where two United Airlines planes flew within 400 feet vertically and half a mile horizontally of each other after an air traffic controller directed a pilot to turn right instead of left.
"You basically crossed directly over the top of each other," a pilot said over the live air traffic report, moments after the May 9 incident. Another said, "I have no idea what was going on over there in the tower, but it was pretty gnarly looking."
FAA rules say aircrafts must remain separated by 1,000 feet vertically and 3 miles horizontally. The agency considers both incidents near Houston "high-risk." The agency identified 41 such high-risk incidents nationwide in 2012, the most recent data available.
"It sounds like the planes were a long way apart but they approach each other pretty fast," said airline analyst Darryl Jenkins. "You can cover a lot of distance pretty quickly."
The traffic near Bush Intercontinental that Thursday was no busier than usual. The traffic flying through Houston's skies was calmer than a typical Thursday, particularly one before the July 4 holiday, said Ryan Jorgenson, aviation analyst with Flight Aware, a Houston-based group that analyzes airport traffic.
"It doesn't ever seem to matter how busy it is," Jorgenson said.
The FAA identified no specific similarities between the recent events near Houston. The agency released a statement about the incidents that said in part, "Air traffic controllers handle more than 130 million air traffic operations a year, and 99.99 percent of those operations occur normally and in full compliance with FAA safety regulations. The FAA builds robust safety margins into the air traffic system and relies on a series of other safety layers to achieve that high level of safety."
Retraining after incidents
The statement said that the agency developed corrective actions after the high-risk incidents including retraining, procedural changes and outreach to pilots.
The NTSB is investigating the May incident, said spokesman Eric Weiss. The board is looking into the circumstances of the second incident but it is not under investigation, he said. The group monitors incidents reported by the FAA and investigates certain events to make recommendations of "either great local import or national significance that others can learn from."
"We try to go through and look at as many incidents as possible to see commonalities to prevent these types of incidents from happening," Weiss said.
Their investigations can lead to recommendations for the FAA and local airports.
Airline analyst Jenkins said that while the high-risk incidents can be nail-biting, actual collisions are very rare.
"Whenever there are humans involved there will be human error," Jenkins said. "But it's not like we have planes flying into each other all the time."
Aviation consultant Mike Boyd said the nation's air traffic control system is several decades old and controllers are often overworked.
"We just need to hope these near misses stay near and don't eventually become collisions. We should be concerned this will only get worse," Boyd said, noting a need for better technology and training for air traffic controllers. "We are safe, but can we be safer? Yes."
More people on fewer flights
The incidents come at a time when passenger traffic at Houston's airports has increased but the number of operations has gone down as airlines streamline their number of flights because of higher fuel prices. In the last five years, passenger traffic at Houston's airports have increased by about 2 million to about 51 million in 2013. Operations at the airports, which include takeoffs and landings, decreased by about 65,000 to just over 808,000 last year, according to the Houston Airport System.
In April, the FAA opened a new air traffic control tower at Bush Intercontinental, the fifth in the Houston area, to handle the expected growth in flight operations. Houston also recently implemented a local component of the FAA's NextGen program, a highly anticipated upgrade to the nation's air travel that basically uses a satellite system as opposed to a radar system. When it launched locally on May 29, inbound planes instantly had two additional lanes to fly through from the northwest and the northeast.
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