19971108032589A

Accident · Destroyed

FAA accident report · Cessna 208B · Barrow, AK · November 8, 1997

Date
November 8, 1997 · 08:08 local
Place
Barrow, AK
Airport
Wiley Post-Will Rogers Mem
Phase of flight
To Init Climb(1st Pwr Reduct)
Operating rules
Air taxi and commuter (Part 135)
Operator
EPUA
Damage
Destroyed
Aircraft
N750GC
NTSB investigation
NTSBANC98MA008
Reported as
Cessna 208B
Reported engine
Pratt & Whitney PT6A114
People aboard
8
Fatal injuries
8
Pilot’s flight hours
3,500 total200 in this make and model

From the FAA’s Accident/Incident Data System (AIDS), through its Aviation Safety Information Portal, as reported. The NTSB investigates accidents separately, and its record of an accident is the fuller one. The aircraft is matched to the registry by N-number and event date, checked against the reported make and model; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

What happened

The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.

Hageland aviation air taxi crashed shortly after take off all 8 POB suff fatal inj. Barrow, AK. (.4)the pilot, who was also the station manager, arrived at the airport earlier than other company employees to prepare for a scheduled commuter flight, transporting seven passengers and cargo to another village during hours of arctic, predawn darkness. Heavy frost was described on vehicles and airplanes the morning of the accident, and the lineman who serviced the airplane described a thin glaze of ice on the upper surface of the left wing. The pilot was not observed deicing the airplane prior to flight, and was described by the other employees as in a hurry to depart on time. The pilot directed the lineman to place fuel in the left wing only, which resulted in a fuel imbalance between 450 and 991 pounds (left wing heavy). The first turn after takeoff was into the heavy left wing. The airplane was observed climbing past the end of the runway, and descending vertically into the water. No preimpact mechanical anomalies were found with the airplane or powerplant. The aileron trim indicator was found in the full right wing down po sition. Postaccident flight tests with left wing heavy lateral fuel inbalances, disclosed that approximately one-half of right wing down aileron control deflection was used to maintain level flight, thus leaving only one-half right wing down aileron control efficacy. Research has shown that frost on airfoils can result in reduced stall angles to attack (often below that required to active stall warning devices), increased in stall speeds between 20% and 40%, asymmetric stalls resulting in large rolling moments, and differing stall angles of attack for wings with upward and downward deflected ailerons (as when recovering from turns).

As the FAA filed it

HAGELAND AVIATION AIR TAXI CRASHED SHORTLY AFTER TAKE OFF ALL 8 POB SUFF FATAL INJ. BARROW, AK. (.4)THE PILOT, WHO WAS ALSO THE STATION MANAGER, ARRIVED AT THE AIRPORT EARLIER THAN OTHER COMPANY EMPLOYEES TO PREPARE FOR A SCHEDULED COMMUTER FLIGHT, TRANSPORTING SEVEN PASSENGERS AND CARGO TO ANOTHER VILLAGE DURING HOURS OF ARCTIC, PREDAWN DARKNESS. HEAVY FROST WAS DESCRIBED ON VEHICLES AND AIRPLANES THE MORNING OF THE ACCIDENT, AND THE LINEMAN WHO SERVICED THE AIRPLANE DESCRIBED A THIN GLAZE OF ICE ON THE UPPER SURFACE OF THE LEFT WING. THE PILOT WAS NOT OBSERVED DEICING THE AIRPLANE PRIOR TO FLIGHT, AND WAS DESCRIBED BY THE OTHER EMPLOYEES AS IN A HURRY TO DEPART ON TIME. THE PILOT DIRECTED THE LINEMAN TO PLACE FUEL IN THE LEFT WING ONLY, WHICH RESULTED IN A FUEL IMBALANCE BETWEEN 450 AND 991 POUNDS (LEFT WING HEAVY). THE FIRST TURN AFTER TAKEOFF WAS INTO THE HEAVY LEFT WING. THE AIRPLANE WAS OBSERVED CLIMBING PAST THE END OF THE RUNWAY, AND DESCENDING VERTICALLY INTO THE WATER. NO PREIMPACT MECHANICAL ANOMALIES WERE FOUND WITH THE AIRPLANE OR POWERPLANT. THE AILERON TRIM INDICATOR WAS FOUND IN THE FULL RIGHT WING DOWN PO SITION. POSTACCIDENT FLIGHT TESTS WITH LEFT WING HEAVY LATERAL FUEL INBALANCES, DISCLOSED THAT APPROXIMATELY ONE-HALF OF RIGHT WING DOWN AILERON CONTROL DEFLECTION WAS USED TO MAINTAIN LEVEL FLIGHT, THUS LEAVING ONLY ONE-HALF RIGHT WING DOWN AILERON CONTROL EFFICACY. RESEARCH HAS SHOWN THAT FROST ON AIRFOILS CAN RESULT IN REDUCED STALL ANGLES TO ATTACK (OFTEN BELOW THAT REQUIRED TO ACTIVE STALL WARNING DEVICES), INCREASED IN STALL SPEEDS BETWEEN 20% AND 40%, ASYMMETRIC STALLS RESULTING IN LARGE ROLLING MOMENTS, AND DIFFERING STALL ANGLES OF ATTACK FOR WINGS WITH UPWARD AND DOWNWARD DEFLECTED AILERONS (AS WHEN RECOVERING FROM TURNS).

NTSB investigation

The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.