Wien Consolidated Airlines Flight 55
Encyclopedia
Wien Consolidated Airlines Flight 55 was a scheduled domestic passenger flight that crashed into Pedro Bay, Alaska
on 2 December 1968, killing all 39 on board. The Fairchild F-27B aircraft was operated by Wien Consolidated Airlines, Inc., later Wien Air Alaska
, and was en route to Dillingham, Alaska from Anchorage. The NTSB investigation revealed that the aircraft suffered a structural failure after encountering "severe-to-extreme" air turbulence. The accident was the second-worst accident involving a Fairchild F-27 at the time, and currently the third-worst accident involving the aircraft.
aircraft that had been in service since 1959. The aircraft was piloted by Captain David Stanley, who had been a pilot for Northern Consolidated Airlines for seven years before that airline was merged into Wien Consolidated Airlines. Prior to that, he had been a flight instructor in Anchorage, and was described as an excellent pilot.
Flight 55 departed Anchorage International Airport at 8:46 AM, and proceeded 150 miles (241.4 km) southeast to Iliamna
, Alaska without reported difficulties. At 9:25 AM, first officer Jerry Svengard contacted Iliamna air traffic control to request an approach clearance, which was granted at 9:26 AM. This was the last outside contact made with the crew of Flight 55.
at 11500 feet (3,505.2 m). Local witnesses reported hearing an explosion and seeing a fireball in the vicinity of the aircraft's tail before it descended in a steep, uncontrolled spiral towards the ground. Other witnesses reported large quantities of black smoke from behind the wing of the aircraft, and that the plane continued on course for a short period of time, before pieces separated from the aircraft and it entered a dive. The aircraft crashed into Spotsy Lake, Pedro Bay, Alaska, an area described as being a frozen marsh
land surrounded by mountains.
Heavy winds gusting up to 55 miles per hour (24.6 m/s), as well as low temperatures of -11 F, hampered search, rescue, recovery, and investigation efforts. An Air Force helicopter was able to reach the crash site that afternoon, but was forced by the wind to take off shortly thereafter. The pilot, Major
Norman Kahmoot, reported that there were no survivors, and that the aircraft had been so disfigured by the crash that it was no longer recognizable. Bodies had been scattered across a large area, and local Eskimo
villagers volunteered to guard the remains from foraging animals until they could be collected and taken to the temporary morgue.
The NTSB investigation lasted 1 year, 7 months. It was discovered that a number of fatigue
cracks had formed on the aircraft's wings due to improper and shoddy maintenance. The area over Pedro Bay had been the site of extreme, unreported turbulence, with winds in excess of 50 knots (27.2 m/s). The stresses due to turbulence
and air pressure caused a structural failure
in the aircraft's right wing, forcing it into a spiraling, uncontrollable dive.
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
on 2 December 1968, killing all 39 on board. The Fairchild F-27B aircraft was operated by Wien Consolidated Airlines, Inc., later Wien Air Alaska
Wien Air Alaska
Wien Air Alaska was formed from Northern Consolidated Airlines and Wien Alaska Airways. The company was famous for being the first airline in Alaska, and one of the first in the United States.-History:...
, and was en route to Dillingham, Alaska from Anchorage. The NTSB investigation revealed that the aircraft suffered a structural failure after encountering "severe-to-extreme" air turbulence. The accident was the second-worst accident involving a Fairchild F-27 at the time, and currently the third-worst accident involving the aircraft.
Flight
Flight 55 was served by a Fairchild F-27B, a twin-engine propjetTurboprop
A turboprop engine is a type of turbine engine which drives an aircraft propeller using a reduction gear.The gas turbine is designed specifically for this application, with almost all of its output being used to drive the propeller...
aircraft that had been in service since 1959. The aircraft was piloted by Captain David Stanley, who had been a pilot for Northern Consolidated Airlines for seven years before that airline was merged into Wien Consolidated Airlines. Prior to that, he had been a flight instructor in Anchorage, and was described as an excellent pilot.
Flight 55 departed Anchorage International Airport at 8:46 AM, and proceeded 150 miles (241.4 km) southeast to Iliamna
Iliamna, Alaska
Iliamna is a census-designated place in Lake and Peninsula Borough, Alaska, United States. The population was 102 at the 2000 census.-Geography:Iliamna is located at ....
, Alaska without reported difficulties. At 9:25 AM, first officer Jerry Svengard contacted Iliamna air traffic control to request an approach clearance, which was granted at 9:26 AM. This was the last outside contact made with the crew of Flight 55.
Crash
While preparing to approach Iliamna, the aircraft encountered extreme turbulenceTurbulence
In fluid dynamics, turbulence or turbulent flow is a flow regime characterized by chaotic and stochastic property changes. This includes low momentum diffusion, high momentum convection, and rapid variation of pressure and velocity in space and time...
at 11500 feet (3,505.2 m). Local witnesses reported hearing an explosion and seeing a fireball in the vicinity of the aircraft's tail before it descended in a steep, uncontrolled spiral towards the ground. Other witnesses reported large quantities of black smoke from behind the wing of the aircraft, and that the plane continued on course for a short period of time, before pieces separated from the aircraft and it entered a dive. The aircraft crashed into Spotsy Lake, Pedro Bay, Alaska, an area described as being a frozen marsh
Marsh
In geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss....
land surrounded by mountains.
Heavy winds gusting up to 55 miles per hour (24.6 m/s), as well as low temperatures of -11 F, hampered search, rescue, recovery, and investigation efforts. An Air Force helicopter was able to reach the crash site that afternoon, but was forced by the wind to take off shortly thereafter. The pilot, Major
Major
Major is a rank of commissioned officer, with corresponding ranks existing in almost every military in the world.When used unhyphenated, in conjunction with no other indicator of rank, the term refers to the rank just senior to that of an Army captain and just below the rank of lieutenant colonel. ...
Norman Kahmoot, reported that there were no survivors, and that the aircraft had been so disfigured by the crash that it was no longer recognizable. Bodies had been scattered across a large area, and local Eskimo
Eskimo
Eskimos or Inuit–Yupik peoples are indigenous peoples who have traditionally inhabited the circumpolar region from eastern Siberia , across Alaska , Canada, and Greenland....
villagers volunteered to guard the remains from foraging animals until they could be collected and taken to the temporary morgue.
The NTSB investigation lasted 1 year, 7 months. It was discovered that a number of fatigue
Fatigue (material)
'In materials science, fatigue is the progressive and localized structural damage that occurs when a material is subjected to cyclic loading. The nominal maximum stress values are less than the ultimate tensile stress limit, and may be below the yield stress limit of the material.Fatigue occurs...
cracks had formed on the aircraft's wings due to improper and shoddy maintenance. The area over Pedro Bay had been the site of extreme, unreported turbulence, with winds in excess of 50 knots (27.2 m/s). The stresses due to turbulence
Turbulence
In fluid dynamics, turbulence or turbulent flow is a flow regime characterized by chaotic and stochastic property changes. This includes low momentum diffusion, high momentum convection, and rapid variation of pressure and velocity in space and time...
and air pressure caused a structural failure
Structural failure
Structural failure refers to loss of the load-carrying capacity of a component or member within a structure or of the structure itself. Structural failure is initiated when the material is stressed to its strength limit, thus causing fracture or excessive deformations...
in the aircraft's right wing, forcing it into a spiraling, uncontrollable dive.
See also
- List of accidents and incidents involving airliners in the United States
- Wien Air AlaskaWien Air AlaskaWien Air Alaska was formed from Northern Consolidated Airlines and Wien Alaska Airways. The company was famous for being the first airline in Alaska, and one of the first in the United States.-History:...