The NTSB has cast broad blame for the Aug. 8, 2009, fatal midair between a privately piloted Piper Lance departing Teterboro and a Liberty Helicopters Eurocopter AS350BA flying an air tour that killed nine over the Hudson River near Hoboken, N.J.
On September 14, the NTSB determined that the probable cause of the accident was the “inherent limitations of the see-and-avoid concept, which made it difficult for the airplane pilot to see the helicopter until the final seconds before the collision, and the Teterboro Airport local controller’s non-pertinent conversation, which distracted him from his ATC duties, including correcting the airplane pilot’s read-back of the incorrect frequency, and the timely transfer of communications for the accident airplane to the Newark Liberty International Airport tower.”
The Board found that contributory factors included “both pilots’ ineffective use of available information from their aircraft’s electronic traffic advisory system to maintain awareness of nearby traffic; inadequate FAA procedures for transfer of communication among ATC facilities near the Hudson River Class B exclusion zone; and FAA regulations that did not provide adequate vertical separation for aircraft operating in the Hudson River Class B exclusion zone.”
Human-factors Issue
Board chairwoman Deborah Hersman summarized the accident as the result of “controllers distracted from their duties and pilots who failed to maintain situation awareness” despite the anticollision warning systems aboard both aircraft. Hersman said, “These technologies are not in and of themselves enough to keep us safe. Strong operating procedures, professionalism and a commitment to tasks at hand are all essential pieces of ensuring safe airspace.”
During the hearing, Hersman also bemoaned what she saw as the multiple failure chain leading to the accident. “What we see in this accident is that a lot of people made a lot of little errors and at the end of the day that’s what culminated in this accident.”
These errors included: the Teterboro controller waiting four minutes to hand off the Piper to Newark; the Piper pilot reading back the wrong frequency for Newark; the Teterboro local controller failing to correct the read-back due to the non-pertinent telephone conversation; and the helicopter flying 100 feet above the 1,000-foot altitude proscribed for the tour route being flown.
The Board members vigorously debated the effect of the helicopter’s altitude on the accident, but it was not listed as either a probable cause or contributing factor in the collision.
Board members praised the FAA for instituting various operational changes in the wake of the crash but remained critical of its failure to institute greater vertical separation in the Hudson River Class B Exclusion Zone. –