On July 9, 1988, a Cessna 170B (registration N2487D) operated by Luchini, Bob was involved in an aviation accident near Anchorage, AK. Investigators recorded the probable cause as: The pilot's failure to maintain adequate separation from a large aircraft while taxiing, resulting in loss of control due to wake turbulence. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A Cessna 170 lost directional control and ground looped while taxiing behind a Boeing 727. The smaller aircraft's left wing was lifted by wake turbulence, causing it to come to rest on its nose.
What happened
The pilot of a Cessna 170 experienced a loss of directional control while taxiing for takeoff at an airport with an operating control tower. The air traffic controller had instructed the pilot to follow behind a Boeing 727 that was also taxiing. During this instruction, the controller issued a specific caution regarding wake turbulence.
Despite the warning, the idle power setting of the larger Boeing 727 generated sufficient wake turbulence to affect the smaller aircraft. The aerodynamic forces caused the left wing of the Cessna to lift upward off the ground. This sudden loss of lateral stability resulted in a ground loop maneuver. The accident sequence concluded when the aircraft came to rest on its nose and left wing.
Findings
The investigation identified wake turbulence as the primary factor contributing to the incident. The proximity of the Cessna 170 to the larger jet during taxi operations, combined with the specific power settings of the Boeing 727, created conditions that overwhelmed the pilot's ability to maintain directional control.
Probable cause
The pilot's failure to maintain adequate separation from a large aircraft while taxiing, resulting in loss of control due to wake turbulence.