Narrative:An amphibious float-equipped de Havilland Canada DHC-3T Texas Turbine Otter, registered N455A, sustained substantial damage when it impacted mountainous tree-covered terrain, about 10 miles northeast of Aleknagik, Alaska. Of the nine people aboard, the airline transport pilot and four passengers died at the scene, and four passengers sustained serious injuries.
One of the passengers killed in the crash was Ted Stevens (86), a former longtime Republican senator. Former NASA administrator Sean O'Keefe was also on board but survived the crash.
At the time of the accident, marginal visual meteorological conditions were reported at the Dillingham Airport, about 18 miles south of the accident site. The weather conditions at the accident site at that time are not known; however, searchers encountered instrument meteorological conditions (IMC) when they arrived at the accident site almost 6 hours later. The flight originated from a GCI-owned remote fishing lodge on the southwest shoreline of Lake Nerka, about 14:30 ADT. The flight was en route to a remote sport fishing camp on the banks of the Nushagak River, about 52 miles southeast of the GCI lodge. No flight plan was filed.
About 18:15 ADT, GCI's lodge manager contacted personnel at the sports fishing camp to inquire about the airplane's proposed return time. The fishing camp personnel told the GCI lodge manager that the airplane had not arrived, and that they assumed that the pilot had chosen a different fishing destination. The GCI lodge manager then initiated a phone and radio search to see if the airplane had diverted to Dillingham, Alaska or if it was en route back to the GCI lodge. Unable to locate the airplane, GCI lodge personnel initiated an aerial search along the pilot's anticipated route. Additional search airplanes and helicopters in the area voluntarily joined the search for the missing airplane. The airplane was officially reported overdue to the Federal Aviation Administration at 18:59 ADT.
About 20:05 ADT, volunteer airborne search personnel located the wreckage along the anticipated flight route, about 900 feet above mean sea level in the Muklung Hills, in steep, heavily wooded terrain, about 19 miles southeast of the GCI lodge.
The closest weather reporting facility was the Dillingham Airport, about 18 miles south of the accident site. At 14:55 ADT, about 10 minutes after the presumed time of the accident, the Dillingham weather observation reported, in part: wind, 180° (true) at 12 knots, gusting to 23 knots; visibility, 3 statute miles with light rain and mist; clouds and sky condition, 600 feet scattered, 1,000 feet overcast; temperature, 52° Fahrenheit (F); dew point, 48° F; altimeter, 29.58 inches of Mercury.
No emergency locator transmitter (ELT) signal was detected during the aerial search. Examination of the wreckage revealed that the ELT had separated from its mounting bracket during impact, and the antenna cable was found separated from the ELT.
Probable Cause:
PROBABLE CAUSE: "The National Transportation Safety Board determines that the probable cause of this accident was the pilot's temporary unresponsiveness for reasons that could not be established from the available information. Contributing to the investigation's inability to determine exactly what occurred in the final minutes of the flight was the lack of a cockpit recorder system with the ability to capture audio, images, and parametric data."
Accident investigation:
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Investigating agency: | NTSB |
Status: | Investigation completed |
Duration: | 297 days (10 months) | Accident number: | NTSB/AAR-11/03 | Download report: | Final report
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Classification:
Sources:
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NTSB Accident Docket» NTSB
» Alaska State Troopers
Follow-up / safety actions
NTSB issued 2 Safety Recommendations
Issued: 05-JAN-2011 | To: FAA | A-10-169 |
Require a detailed inspection, during annual inspections, of all emergency locator transmitters installed in general aviation aircraft to ensure that the emergency locator transmitters are mounted and retained in accordance with the manufacturers specifications. (Closed - Reconsidered) |
Issued: 05-JAN-2011 | To: FAA | A-10-170 |
Determine if the emergency locator transmitter (ELT) mounting requirements and retention tests specified by Technical Standard Order (TSO) C91a and TSO C126 are adequate to assess retention capabilities in ELT designs. Based on the results of this determination, revise, as necessary, TSO requirements to ensure proper retention of ELTs during airplane accidents. (Closed - Acceptable Action) |
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Photos
accident date:
09-08-2010type: de Havilland Canada DHC-3T Texas Turbine Otter
registration: N455A
accident date:
09-08-2010type: de Havilland Canada DHC-3T Texas Turbine Otter
registration: N455A
accident date:
09-08-2010type: de Havilland Canada DHC-3T Texas Turbine Otter
registration: N455A
Map
This map shows the airport of departure and the intended destination of the flight. The line between the airports does
not display the exact flight path.
Distance from Lake Nerka-GCI Lodge, AK to Nushagak River-sport fishing camp, AK as the crow flies is 70 km (44 miles).
Accident location: Exact; as reported in the official accident report.
This information is not presented as the Flight Safety Foundation or the Aviation Safety Network’s opinion as to the cause of the accident. It is preliminary and is based on the facts as they are known at this time.