ANC18LA072 · Cessna 182
Cessna 182 · Accident: turbulence encounter en route
From Big Lake, AK to Lake Hood Seaplane Base (LHD)
Event
- NTSB case
- ANC18LA072
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Cessna 182
- Aircraft type
- Cessna 182
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N2571G
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Big Lake, AKTo Lake Hood Seaplane Base (LHD), Anchorage, AK
- Aircraft age
- About 59 years (built 1959)
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- En route · descent
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Turbulence encounter
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Environmental issues › Conditions/weather/phenomena
- Personnel issues › Action/decision
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
While the accident airplane was inbound for landing, the pilot received traffic and wake turbulence advisories from air traffic control for a crossing heavy Boeing C-17 on approach. The pilot acknowledged that he had the C-17 in sight and elected to execute a 360° turn. After completing the turn, he descended the airplane below the altitude of the C-17, ultimately crossing 3.66 miles behind and about 500 ft below the C-17's flightpath. Shortly after passing behind the C-17, the pilot reported entering an area of "severe turbulence," which he described as "one violent instantaneous motion." The airplane continued for a landing.
The pilot reported that, during a postflight inspection of the airplane, he discovered that both wings and the horizontal stabilizer exhibited signs of buckling. Further, the left wing had shifted aft, which reduced the gap between the trailing edge of the flap and the fuselage by 3/8 of an inch. A crack in the left wing spar was discovered during a subsequent, detailed postaccident examination. Federal Aviation Administration guidance indicates that pilots should fly at or above the preceding aircraft's flightpath, altering course as necessary, to avoid the area behind and below the generating aircraft.
Probable cause
The pilot's failure to avoid wake turbulence from a crossing heavy airplane.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ANC18LA072
- Event ID
- 20181001X33722
- Case number
- ANC18LA072
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: local date, investigation status, coordinates. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 2018-09-27.
- API snapshot SHA-256: a72aad4661444d608cf5a79d807b6ade7dcffc300063b8bcef3da15699bc7458; retrieved 2026-09-16T08:17:11.508Z.