It is clear that something was terrible on the night of January 29, when a black hawk helicopter of the army crashed with an American Airlines regional plane on the Potomac River near Ronald Reagan National Airport, killing everyone aboard the plane.
But an error did not cause the worst domestic accident in the United States in almost a quarter of a century. Modern aviation is designed to have dismissals and safeguards that prevent a false step, or even several false steps, of being catastrophic. On January 29, that system collapsed, found an investigation by New York Times.
Until now, the attention has focused on the altitude of the Black Hawk, which was too high and placed it directly on the airway of the plane. But the times discovered new details that show that the failures were much more complex than it was previously understood.
Here are five investigation conclusions:
The Black Hawk team could not execute a common but sometimes dangerous aviation practice.
The practice, known as flying under the rules see and avoid, works exactly as it sounds. A pilot is a jersey to see neighboring air traffic, often without the help of the air traffic controller, and avoid floating in place until the traffic passes or flying around him prescribed.
A benefit of the seeing and avoiding system is that it can lighten the workload of the controller that rotates the occupied periods. But seeing and avoiding has proven problematic, simply mortal, in recent decades. He has also involved the leg in at least 40 fatal collisions since 2010, according to the National Board of Transportation Security.
On the night of the accident, the Black Hawk team did not run to see and avoid effective. The pilots did not detect the specific passenger jet that the controller had marked, or could not pivot to a safer position. The result is that they flew directly to the 5342 flight of American Airlines while trying to land at the National Airport.
The air traffic controller could have given a more urgent warning that the two aircraft were converging.
He thought that the service air traffic controller that night had delegated the main responsibility to evade another air traffic to the Black Hawk team, continued to monitor the helicopter, as required by his work. However, he did not issue clear and urgent instructions to Black Hawk to avoid accident, they say aviation experts.
As the two planes approached each other, the controller issued an instruction to the helicopter crew: pass behind the plane.
Some former military pilots said that when issuing that command, the controller went beyond their obligations, especially in a position to see and avoid, and that an experienced Black Hawk helps help.
Even so, some regulators and drivers said the controller in this case could have done more.
He could have told Black Hawk Crew where flight 5342 was placed and how it was tied. (The Federal Aviation Administration Manual instructs direct controllers to use the hours of a clock in locations that describe). He was also able to test the distance from the jet from the helicopter in nautical miles or feet.
But one thing is critical. When two aircraft are ongoing collision, the main priority of the controller must be to warn both pilot sets. “Advise the pilots if the objectives are likely to merge,” say the FAA regulations.
That did not happen.
Technology did not work as planned.
Radio Communications, the media proven and true interaction between controllers and pilots were also broken. Some of the controller’s instructions “stepped on”, which means that they were cut when the helicopter crew pressed a microphone to speak, and the information is probably not heard.
The Black Hawk technology that would have allowed controllers better to track the helicopter was off. The Black Hawk did not operate with technology due to the confidentiality of the mission through which it practiced its crew. That is because
As a result, the disturbing controller in pings of the helicopter transpondor to show its changing location in the radar, which can take between five and 12 seconds to refresh, according to the FAA documents.
In an occupied airspace, that period, said Michael McCormick, former vice president of the FAA air traffic organization, is “a long time.”
The helicopter route was flying and the track of the plane he was using to land formed a particularly dangerous combination.
Near the end of its turn, the controller that handles helicopters and commercial airplanes tried to achieve a complicated and potentially risky maneuver controller refer as a compression game.
That is an attempt to keep moving operations efficiently by traffic sequence of the track with a minimum time between takeoffs or landings, according to the veteran controllers of the National Airport.
Wichita’s flight 5342, Kan, was supposed to be part of that maneuver. To achieve this, the controller obviously decided to land that flight not on track 1 commonly used, but on track 33 little used.
Track 33 had a peculiarity: a particularly narrow vertical space between the landing slope for a stream and the maximum altitude to which the helicopters who use a certain route, called Route 4, could fly.
At its highest point, near the eastern shore of Potomac, the vertical distance between a helicopter and a plane and a route to land on track 3 would be 75 feet, NTSB researchers said. But if a helicopter flew further from the east shore from the river to the airport, that distance would be only minor.
With such little margin of error, it would be crucial for the vuele helicopter below the maximum altitude for the route.
The Black Hawk that night flew higher than that, putting everyone in both aircraft in danger.
Black Hawk pilot could not pay attention to a co -pilot directive to change course.
The army crew mission was to carry out an annual evaluation of the Captain. Rebecca M. Lobach, to ensure that his helicopter pilot skills were up to it.
That night, its assignment was to navigate the conditions of a scenario in which the members of the Congress or other high government officials may need to be carried out in the capital of the nation in case of an attack. NCOs Andrew Loyd Eaves was the instructor.
In the last seconds before the impact, the anchorial eager told Captain Lobach that the air traffic controller wanted her to turn left.
Turning left would have opened more space between the helicopter and flight 5342, which was heading to track 33 at an altitude of approximately 300 feet. But there is no indications that she has returned to the left. Instead, the helicopter flew directly to the plane.
