Fuel Lever, Floats Factor Large in NYC Helicopter Crash

A recently released National Transportation Safety Board (NTSB) preliminary report on the fatal doors-off March 11 helicopter photo flight in New York officially reveals the pilot's version of events and the fact that the right-side emergency tri-floats appear to have not been fully inflated at the time of impact. The accident killed all five passengers after the Airbus Helicopters AS350B2 lost power and autorotated into the East River and then rolled over on its right side to inverted after impact. The flight was operated by Liberty Helicopters for FlyNYON under the photo exemption of Part 91.

Last week, the Federal Aviation Administration formally issued an emergency order prohibiting use of supplemental passenger-restraint systems that cannot be released quickly in commercial doors-off operations. The March 22 order further prohibits doors-off flight operations unless passengers are secured with FAA-approved restraints.

The pilot, Rick Vance, escaped with minor injuries and subsequently told investigators of trying to restart his helicopter's engine after a portion of a passenger's supplemental harness possibly snagged the fuel shutoff lever into the off position.

Post-accident wreckage examination by the NTSB also found that “the three floats installed on the left landing gear skid appeared to be more inflated than the floats on the right landing gear skid. The emergency floats' left pressurization gas cylinder gauge indicated about zero psi (pounds per square inch), while the right pressurized gas cylinder gauge indicated about 4,000 psi.

The NTSB performed a functional check by actuating the cyclic trigger, which is used to activate the floats. The trigger mechanism was smooth, with no evidence of binding, the Board said. In addition, “continuity of the float system control was established between the trigger, dual cable block, and the activation cable clevis connection. When the trigger was released, the dual cable block returned to its normal position (via spring within the junction box), but the upper and lower turnbuckles remained in their actuated positions.”

In interviews with investigators, the pilot said the sole front-seat passenger turned sideways, slid back toward him on the two-place bench seat next to the pilot position to take photos. (Photos provided to BJT sister publication Aviation International News  show that the accident helicopter was configured with a right-hand pilot-in-command configuration.) Then during a right turn the pilot received an aural low rpm warning in his headset, observed engine and fuel pressure warning lights, and believed he had experienced an engine failure.

He lowered collective and continued with the right turn toward the East River, told passengers to get back into their seats, tried an engine restart, checked the fuel-control lever and found it in the normal detent, and activated the float system at approximately 800 feet agl (height above ground level). At that point, committed to impact, the pilot reached down for the emergency fuel-shutoff lever, and noticed it was already in the off position and that a portion of the front-seat passenger tether was underneath the lever.

Descending through 600 feet, the pilot said he repositioned the lever to the on position and attempted a restart, observing positive engine indicators, but had to continue with the autorotation as the engine “wasn't spooling up fast enough.” He switched the shutoff lever back to off before impact at an estimated five to 10 degrees nose up.

During the NTSB wreckage investigation “the fuel-control lever was found in the off position. The fuel-shutoff lever was found in the open position. The snapwire (witness wire) between the fuel-shutoff lever and the engine control housing was broken at its lower end where it is normally secured through a hole in the control housing.”

The pilot reported that after impact, the helicopter quickly filled with water and rolled past 45 degrees. He made a fast attempt to unscrew the front-seat passenger's carabiner, attached to a floor hardpoint, before releasing his own restraint and exiting the helicopter after it had filled with water.

FlyNYON provided the passengers with nonstandard harnesses that allowed them to lean out helicopter door sills for the photo flights. In the event of an emergency, passengers were supposed to cut themselves out of these harnesses with an integrated knife located in a holder on the front strap of the harness.