The NTSB's investigation into the fatal March 11 crash of a “doors off” helicopter photo tour flight into New York's East River will continue for months, but key areas of interest likely will be the supplemental passenger restraint systems, the fuel shutoff control, and the emergency pop-out floats.
N350LH was a 2013 Airbus Helicopters AS350B2 owned by Meridian I Consulting and operated by Liberty Helicopters for FlyNYon. It was operating under the Part 91 aerial photography exemption, with five passengers and one pilot aboard when it crashed at approximately 7:08 p.m, 11 minutes after takeoff from the Helo Kearny (65NJ) heliport in Kearny, New Jersey. Moments after being cleared into Class B airspace at 2,000 feet, pilot Richard Vance, 33, radioed a mayday call and indicated an engine failure.
Amateur video showed Vance performing an autorotation into the East River in low light, glassy water conditions and making a slightly nose-high, hard landing. The impact point was just north of Roosevelt Island at 86th Street. The helicopter immediately rolled right with main blades churning into the water, where it rolled inverted. The water temperature at the time was estimated to be below 40 degees F and the river current at five knots. Vance emerged from the wreckage within 90 seconds and was taken aboard an New York Fire Department (FDNY) tug. However, it took rescuers considerably longer to free the passengers—all in their 20s and 30s—described as “tightly harnessed” by the FDNY, and all were pronounced dead either at the scene or later at area hospitals.
The NTSB said it is investigating the accident on a variety of fronts with the help of wreckage teardowns, personnel and witness interviews, and recovered devices and equipment from the helicopter including a Go-Pro camera and an Appareo Vision 1000 and memory card. On March 15, the NTSB reported that a teardown of the helicopter’s engine and examination of the flight controls revealed no evidence of abnormalities, failures, or malfunctions.
While the exact cause of the accident remains under investigation, Vance reportedly has told investigators that a passenger harness became entangled with the floor-mounted fuel cutoff control next to the collective. (In the photo below it is the red handle closest to the collective. In the AS350B3 variant, this control is located on the ceiling.)
Regardless of the cause of the engine shutdown, the pilot apparently had few options and little time at or below 2,000 feet, as cleared by ATC. Autorotations at 65 knots per the Airbus flight manual trigger a descent rate of 1,800 feet per minute, and he was heavy with a full passenger load. The NTSB will be looking at the particulars of the maneuver and the deployment of the tri-bag pop-out float system and its maintenance history. Several post-accident photos appear to show partial inflation of the system on the starboard side, the side of the rollover direction, but they are not conclusive. The typical tri-bag float system requires semi-annual, annual, and three-year inspections, with full inflation during the last. They also typically have a maximum forward deployment speed. However, even if the floats were functioning properly, that was no guarantee that the helicopter was going to stay upright, according to a 1996 FAA study, the last of its kind, titled, “Survey and Analysis of Rotorcraft Flotation Systems.” The study concluded, “Rotorcraft, in both ditching and water impact scenarios, were found to overturn immediately upon impact. Overturns occurred to rotorcraft both with and without deployed floats.”
At the time of the 1996 study, the FAA recommended supplemental floats placed near the top of the aircraft to prevent rollovers.
On doors-off photo flights, passengers wear supplemental harnesses that allow them to hang out the sides of the door sills. Aviation photojournalist Eric Adams, who was on one of the other two photo flights that took off with N350LH on March 11, told AIN that the harness is secured by a carabiner, a D-shaped coupling link with a safety closure, used by rock climbers, and that the tether attached to the harness “has a modest amount of slack, but not enough that you can get very far out of the cabin.” For rear seat passengers, the D-ring attaches to mounts on the rear cabin wall. There is a harness-cutting knife on the forward strap of the harness in a plastic enclosure, and in an emergency occupants are supposed to use that to extricate themselves, as opposed to reaching behind their backs and unscrewing the D-ring. “The average person on the street wouldn't recognize it as a knife or know how to use it,” Adams told AIN.
Not being able to find the harness knife may not have been the passengers' biggest problem, according to Adams. None of them were wearing appropriate clothing, he said, not to mention survival suits to help endure a wintertime ditching. According to the U.S. Coast Guard, sudden immersion into water even as warm as 69 degrees F can produce a phenomenon called “cold water shock” that can trigger cardiac arrest, involuntary gasp reflex, and loss of muscle coordination even in young, healthy people.
Since the crash, Sen. Charles. Schumer (D-New York), a longtime critic of the city's helitour industry, called on the FAA to revoke Liberty's operating certificate. Liberty is suspending all open-door flights pending conclusion of the NTSB investigation. The family of the front-seat passenger, Trevor Cardigan, 26, is suing Liberty, charging negligence.
The Helicopter Association International (HAI) restated its long-standing opposition to doors-off/open helitours and the FAA issued a statement saying it was examining the use of supplemental/substitute harnesses on photo flights.
On March 16 the FAA issued the following statement via Twitter: “Helicopter pilots and consumers should be aware of the hazard from supplemental restraint devices during an emergency evacuation during 'doors off' flights. The FAA will order operators and pilots to take immediate action to control/mitigate this risk. Until then, the FAA will order no more 'doors off' operations that involve restraints that cannot be released quickly in an emergency. Additionally, the FAA will conduct a top-to-bottom review of its rules governing these flights to examine any potential misapplication that could create safety gaps for passengers."