Accident at New York, New York, 11 Mar 2018 (N350LH)

Accident narrative

On March 11, 2018, about 1908 eastern daylight time, an Airbus Helicopters AS350 B2, N350LH, lost engine power during cruise flight and ditched into the East River in New York, New York. The pilot sustained minor injuries, and the five passengers drowned. The helicopter was substantially damaged. The flight was operated by Liberty Helicopters Inc. under a contractual agreement with NYONair as a FlyNYON-branded, doors-off aerial photography flight.

### The flight

The intended 30-minute local flight departed from Helo Kearny Heliport in Kearny, New Jersey, about 1850 under visual flight rules. No flight plan was filed. For the flight, Liberty configured the helicopter with the two right doors and the front left door removed, and the left sliding door locked open. The pilot, 33, had about 3,100 hours of total flight experience, including 1,430 hours as pilot-in-command in the AS350.

Before departure, each passenger was fitted with a NYONair-provided harness/tether system intended to prevent them from falling out of the helicopter. The system consisted of a full-body workplace fall-protection harness secured with a locking carabiner to a tether. The other end of the tether was secured with a second locking carabiner to an anchor point in the cabin. Passengers were also provided with a pouch containing an emergency cutting tool. Each passenger wore the helicopter's installed, FAA-approved restraints over their harness. The pilot wore only the installed, FAA-approved restraint.

### The accident sequence

The flight traveled south toward the Statue of Liberty at altitudes between 300 and 500 feet above ground level. Consistent with standard operating procedures for FlyNYON flights, the pilot instructed the two passengers in the rear inboard seats that they could remove their installed, FAA-approved restraints and sit on the cabin floor. The outboard passengers were allowed to rotate outboard in their seats.

At 1903:46, the pilot contacted air traffic control at LaGuardia Airport and requested a route up the East River to Central Park. The flight proceeded north and climbed to 1,900 feet mean sea level. Onboard video showed that the front passenger, facing outboard with his legs outside the helicopter, leaned back several times to take photographs. Each time he leaned back, the tail of the tether attached to the back of his harness hung down loosely near the helicopter’s floor-mounted controls.

At 1905:51, the front passenger resumed a more upright position, and his tether tail appeared taut, extending toward the floor-mounted controls. At 1906:08, he pulled on a hand grip to adjust his seating position. The tether tail remained taut but appeared to pop upward. Two seconds later, ambient engine sounds decreased, and the helicopter began to descend.

The pilot stated he heard a low rotor rpm alert and saw engine oil and fuel pressure warning lights illuminate. He lowered the collective to maintain rotor rpm, initiated an autorotative descent, and turned toward the East River. During the glide, he engaged the engine starter, but the engine did not relight.

When the helicopter was about 600 feet above the river, the pilot reached down to activate the floor-mounted fuel shutoff lever (FSOL) and found it was already in the shutoff position. He noticed the tail of the front passenger's tether had caught on the FSOL and pulled it up. The pilot pushed the FSOL down and engaged the starter, seeing an immediate rise in engine temperature, but the helicopter was too low to restart the engine.

At 1907:02, at an altitude of about 100 feet, the pilot pulled the activation handle to deploy the emergency flotation system. He heard a "pop" and saw parts of the front floats. The helicopter touched down on the water at 1907:15. Witnesses' videos showed the helicopter touched down upright but immediately began to roll to the right. Within about 11 seconds of touchdown, the helicopter was completely inverted and submerged.

### Emergency egress

The pilot stated that he attempted to open the locking carabiner on the front passenger's tether, but the helicopter was rolling rapidly. He was fully underwater by the time he released his own restraint and egressed.

Onboard video captured the passengers' attempts to escape. The rear-left inboard passenger reached toward his cutting tool pouch and asked how to cut the tether, but did not free himself. None of the passengers were able to egress. Divers later recovered the passengers, using knives to cut various straps. The medical examiner listed the cause of death for all five passengers as drowning.

### What the investigation found

**The fuel shutoff lever** The Board concluded that the tail of the front passenger’s tether caught on the FSOL during the flight, inadvertently activating it and interrupting fuel flow to the engine.

**The emergency flotation system** The floats inflated partially and asymmetrically because only the left gas reservoir discharged. Postaccident testing revealed that a force exceeding 58 pounds was required to pull the activation handle fully aft to activate the right reservoir. This high pull force resulted from an installation anomaly where the pull-cable junction box was installed aft of its specified location, creating a bend in the cable. The pilot, hearing the first reservoir discharge and feeling the high resistance, mistakenly believed he had pulled the handle fully.

The Board found that the float manufacturer did not specify a pull-force limitation for the handle, and the FAA's certification review did not identify this omission. Furthermore, buoyancy stability testing showed that even if the gas from a single reservoir had been symmetrically distributed, the helicopter would not have remained upright in the water.

**The harness/tether system** The Board concluded that Liberty and NYONair's decision to use locking carabiners and ineffective cutting tools as the primary means for rapid release was inappropriate and unsafe. Minimally trained passengers would have great difficulty extricating themselves during an emergency. The Board found the landing was survivable, but the harness/tether system contributed to the fatalities by hindering egress.

**Organizational and management issues** The investigation identified ineffective safety management at both Liberty and NYONair. Liberty allowed NYONair personnel, particularly its chief executive officer, to influence core aspects of operational control. Liberty and NYONair pilots had previously raised concerns about the harnesses and the ineffectiveness of the cutting tools. However, NYONair's CEO dismissed the concerns, stating the existing harnesses were safe and instructing pilots not to delay flights over the issue. The Board concluded that ineffective safety management resulted in a lack of prioritization and mitigation of foreseeable risks.

**FAA regulations and oversight** Liberty and NYONair operated the flights under Part 91 by claiming the "aerial photography" exception. The Board concluded the companies exploited this exception to avoid the additional FAA requirements and oversight that apply to commercial air tours. The FAA principal operations inspector assigned to Liberty did not conduct additional surveillance after learning of the FlyNYON flights.

The Board also expressed concern over the FAA's post-accident approval process for supplemental passenger restraint systems (SPRS), noting it was inadequate because it did not provide guidance to evaluate aircraft-specific installations or entanglement potential.

**Passenger intoxication** Toxicology testing indicated the front passenger had a blood ethanol level of 0.18 gm/dl. While the passenger was intoxicated, the Board concluded that the risk of the tether entangling the floor-mounted controls existed independently of passenger intoxication and most likely depended primarily on the passenger's positioning in the cabin. However, the Board noted that neither company had policies or training to identify and deny boarding to impaired passengers.

### Probable cause

The National Transportation Safety Board determined the probable cause of this accident was Liberty Helicopters Inc.’s use of a NYONair-provided passenger harness/tether system, which caught on and activated the floor-mounted engine fuel shutoff lever and resulted in the in-flight loss of engine power and the subsequent ditching.

Contributing to this accident were (1) Liberty’s and NYONair’s deficient safety management, which did not adequately mitigate foreseeable risks associated with the harness/tether system interfering with the floor-mounted controls and hindering passenger egress; (2) Liberty allowing NYONair to influence the operational control of Liberty’s FlyNYON flights; and (3) the Federal Aviation Administration’s inadequate oversight of Title 14 Code of Federal Regulations Part 91 revenue passenger-carrying operations.

Contributing to the severity of the accident were (1) the rapid capsizing of the helicopter due to partial inflation of the emergency flotation system and (2) Liberty and NYONair’s use of the harness/tether system that hindered passenger egress.