Accidents: Factual Report - BIRD STRIKE EYED IN FATAL SIKORSKY CRASH

 - December 1, 2010, 8:15 AM

Sikorsky S-76C++, Morgan City, La., Jan. 4, 2009–The helicopter was on a Part 135 VFR flight from PHI’s Lake Palourde Heliport to an offshore oil platform when it crashed into a marsh approximately seven minutes after takeoff, killing the two pilots and six of the seven passengers on board.

The helicopter was substantially damaged. There were no reported distress calls. Data retrieved from the helicopter’s cockpit voice and flight data recorder showed that it was in level flight at 850 feet msl at around 135 knots when a loud “bang” was heard followed by the sounds consistent with rushing wind, engine power reductions, and a decrease in rotor speed.

Examination of the wreckage revealed concentric ring fractures on the pilot-side windshield, along with a puncture hole in the roof above. Swab tests identified the microscopic remains of a hawk. Investigators took additional remains from the empennage, the engine inlets, air filters and the main rotor blades and hub.

Current regulations for transport-category helicopters include a requirement that at a minimum the helicopter should be capable of a safe landing after impact with a 2.2-pound bird at a specific velocity, but FAA requirements for helicopter windshields do not mention bird-strike resistance, specifying only that they should not break into dangerous fragments. Two years before the accident, the operator replaced the original laminated glass windshield in the helicopter with STC-approved units made from lighter-weight acrylic.