Cessna 182 N2571G accident near Anchorage, Alaska

Probable cause

The pilot's failure to avoid wake turbulence from a crossing heavy airplane.

NTSB analysis

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.

Text from the NTSB. Open the NTSB docket for ANC18LA072 for the full record.