Casualties unknown

1993-07-24: Cessna 172 (N51409) — Pacific Flight Services — Vacaville, CA

Vacaville, CA, US

On July 24, 1993, a Cessna 172 (registration N51409) operated by Pacific Flight Services was involved in an aviation accident near Vacaville, CA. Investigators recorded the probable cause as: THE PILOT'S IMPROPER IN-FLIGHT PLANNING/DECISION BY FAILING TO ALLOW ENOUGH TIME FOR THE ROTOR WASH TO DISSIPATE BEFORE ATTEMPTING THE APPROACH. THE WAKE TURBULENCE (ROTOR WASH) WAS A FACTOR IN THIS ACCIDENT. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive; 10 related events involving the same aircraft type or operator are linked below.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 1781061362Data APIEditorial standards

An airplane was cleared for a straight-in approach to Runway 20 behind a large helicopter. After encountering turbulence near the threshold, the pilot initiated a go-around. During the go-around, severe turbulence resulted in loss of control; the airplane struck the runway and skidded to a stop.

Approach Clearance and Wake Turbulence Warning

The local controller issued clearance for the flight to conduct a straight-in approach to Runway 20. The controller instructed the pilot to follow a large helicopter that was ahead on the approach. In addition, the controller provided a caution to the pilot that possible existing wake turbulence might be encountered due to the preceding helicopter.

Encounter with Turbulence and Go-Around Decision

While the airplane was nearing the runway threshold, the pilot experienced some turbulence. In response to this turbulence, the pilot opted to perform a go-around procedure.

Severe Turbulence During Go-Around and Loss of Control

During the go-around maneuver, the airplane encountered turbulence of a more severe nature. The pilot lost the ability to control the airplane, and the aircraft struck the runway surface. After impact, the airplane skidded along the runway until it came to a stop.

Wind Information

The pilot reported that the surface wind direction was 180 degrees, with a speed of 10 knots gusting to 15 knots.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001211X12958. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.