On the 8th of August 2009 a small aircraft and a helicopter crashed over the Hudson and all 9 passengers were killed. In the following days the media announced the traffic controller who supposedly was following the small plane had been chatting on the phone with a friend just before the collision. Transcripts of his joking conversations about dead cats and barbeques were published in many papers and the controller and his supervisor were put on leave. The investigation showed that the controller had followed the procedure correctly by transferring the aircraft to the Newark control center. He did not inform the pilot of potential conflicts but he could have not warned the pilot about the helicopter because that aircraft was not visible on his radar.
Like in the case of the Metrolink train crash, the context of the accident was highly risky and as some experts declared in the following days: “an accident was waiting to happen”. The area on the Hudson where the aircraft were flying is an unregulated area were pilots fly free of air traffic control. Every day there are more than 250 unregulated aircraft flying in that corridor and the National Transport Safety Board had already called for a better regulation of the area.
The accident
The 2009 Hudson River mid-air collision was a flight accident that occurred on August 8, 2009, at 11:56 a.m., in which nine people died when a tour helicopter and a small private airplane collided over the Hudson River. The aircraft were in an area known as the "Hudson River VFR Corridor", which extends from the surface of the river to altitudes of 800 to 1,500 feet (240 to 460 m) at various locations along the Hudson River in the immediate area of New York City. Within this corridor, aircraft operate under visual flight rules, under which the responsibility to see and avoid other air traffic rests with the individual pilots rather than with the air traffic controller. Because of the heavy commercial air traffic into La Guardia, Newark and Kennedy airports, small aircraft are restricted from much of the airspace around the city. Many small airplanes that need to transit the New York metro area use the VFR corridor as an alternative to going east of the city (over water) or west towards Pennsylvania. The corridor is also heavily used by helicopter tour companies, which take passengers on sight-seeing tours of the New York.
The helicopter, carrying five Italian tourists and its pilot, took off from the West 30th Heliport at 11:52 a.m. At about the same time, Teterboro tower radioed the Piper at take-off requesting him to pick his flight path towards Ocean City, and once the pilot indicated he would go via the Hudson river,he was instructed to contact Newark airport, and the pilot acknowledged the instruction. However, he did not contact the tower at Newark. Soon after, a controller at Newark who was concerned about aircraft in the plane's path contacted the Teterboro controller and asked him to attempt to re-establish contact. After some unsuccessful attempts to contact the plane, a radar alert about a possible collision occurred in both the Newark and Teterboro towers. However, the two controllers did not remember seeing or hearing the alert. While heading south down river, the plane was seen to be behind the sightseeing helicopter, which was going about half as fast. The pilot of another helicopter saw the impending accident and attempted to warn both the airborne helicopter and the plane by radio but received no response. The wing of the Piper plane hit the helicopter and both aircraft plunged into the river.
On August 14, 2009, the NTSB released a report regarding the incident. The report discussed several aspects of the collision, including locations of origin of the aircraft, planned destination, and air traffic control communications. In addition, the report discussed how one of the controllers at Teterboro Airport was on a phone call and did not warn the airplane pilot of the potential conflict. The air traffic controller in the minutes before the crash and just after handing off the Piper to Newark, had been joking on the phone with a colleague at the Teterboro Operations about barbequeing a dead cat that had been found on the parking lot. He had been using an internal line to call her and had been resuming a conversation that had started some minutes earlier before he handled the Piper.
The National Air Traffic Controllers' Union then issued their own press release disputing some of the phrasing in the NTSB's report. The NTSB then retracted some of its statements regarding the controller's part in the crash, saying that the controller could not have warned the plane about the helicopter because the tour helicopter was not on the controller's radar. Due to the accident, the Federal Aviation Authority put the controller and his supervisor on leave and made comments about their actions.
Analysis of the accident
This case is not yet fully resolved and there does not seem to be a final statement by the NTSB regarding the causes and the responsibilities of the different actors in the event. The phone conversation of the controller did not seem to be identified as a primary cause but it somehow reduced his level of vigilance and communication with the pilot after he had “handed the plane off” to the following control center.
In our view this case exemplifies one of the mechanisms that are associated with personal phone calls from the workplace : calls or other forms of private contact are often made in down times when there is a feeling that a task has been achieved. There is a cycle of activity and when there is a sense that there is a break in the cycle either because the task is completed or because the person has to wait for the next cycle, then emerges an opportunity for a conversation.
In this case, the controller probably had a sense of closure of the activity regarding the Piper plane, it had been “handed off”, and did not have anything else urgent on his screen and therefore he resumed his call. He dropped the conversation as soon as he received a call from the Newark control centre. The question of his responsibility therefore lies in whether he “closed” his activity too soon. Whether in other words he should have followed the plane longer or ensured that contact had been made with Newark or had informed him better. The question is, if he hurried the transfer because he wanted to resume the conversation with his friend (with whom obviously he shouldn’t be conversing in any case).
Using personal calls as break fillers, small rewards for tasks accomplished, or ways to counteract the dullness of an activity is very common. It seems to be the normal strategy to initiate a contact. People don’t just drop what they are doing but wait for one of these moments unless they are interrupted by an incoming contact. The sense of closure or waiting for the next task depends on the nature of the activity as well as personal disposition. Different activities have different cycles and therefore down moments or closures can have different frequencies. Clearly there are also limitations in people’s attention cycles.