FAA Urged to Require Bird Strike-Resistant Helicopter Windshields
Actual bird strikes and testing prove cast acrylic windshields are not sufficiently resistant, the National Transportation Safety Board says in a new accident report.
A oil rig transport helicopter crash in January 2009 that killed eight occupants near Morgan City, La., was caused by the impact of a female red-tailed hawk with the aircraft, the National Transportation Safety Board said in a Nov. 24 final report on the crash. The report recommends that FAA not allow helicopter operators to replace strike-resistant windshields with less-protective ones, as was done in this helicopter prior to the crash, according to NTSB.
NTSB cited the lack of requirements for bird strike-resistant windshields as a contributing factor in the crash.
The crash occurred Jan. 4, 2009, and involved a dual-engine Sikorsky S-76C++ helicopter registered to and operated by PHI, Inc. about seven minutes after takeoff from Amelie, La. Both pilots and six of the seven passengers aboard died in the crash. According to the report, the helicopter was at 850 feet and traveling at 135 knots "when the cockpit voice recorder recorded a loud bang, followed by sounds consistent with rushing wind and a power reduction on both engines." Seconds later, the helicopter crashed.
The safety board said the impact of the bird on the canopy just above the windshield "likely jarred the fire extinguisher T-handles out of their detents and moved them aft, pushing both engine control levers into or near the flight idle position, reducing fuel to both engines. The pilots were probably disoriented from the broken windshield and rushing air and were unable to react in time to maintain control of the helicopter."
The helicopter was originally equipped with laminated glass windshields that complied with European bird-strike resistance standards. PHI replaced them with aftermarket cast acrylic windshields that did not meet any bird-strike resistance standard, according to the report.
NTSB's recommendation letter is available here.