A Cirrus hits an area with known turbulence (and a parachute is deployed)

General Aviation News will often reprint accident reports from the National Transportation Safety Board (NTSB), including one from September 2010 that involved a Cirrus SR22 in Mathias, West Virginia, that encountered serious turbulence and was forced to deploy the aircraft’s ballistic recovery parachute system.

According to the accident report, the pilot was near the end of a two-hour cross-country flight in IFR conditions and flying a holding pattern around the initial approach fix while waiting for weather conditions to improve at his destination airport. While in this holding pattern, the pilot learned that the winds were calm on the surface but higher up, there were wind gusts of up to 40 knots.

After holding for about 15 minutes, the pilot decided to execute the instrument approach but while descending to the final approach fix, the aircraft slowed, the turbulence worsened and the autopilot disengaged. After several pitch and roll oscillations, the aircraft pitched to an attitude of 86° nose down and hit a maximum airspeed of 171 knots and 3.29 Gs – causing the pilot to loose control.

The pilot then deployed the Cirrus’s whole-airframe ballistic recovery parachute system – resulting in the aircraft coming to rest in the woods approximately 25 feet above the ground and 10 nautical miles from the destination. There was one serious injury, one minor injury and one substantially damaged aircraft.

Why the autopilot disengaged was not determined, but it was likely due to a very brief activation of the stall warning or a possible (inadvertent) manual disengagement. However, the forecasted weather for the flight did include widespread instrument meteorological conditions along with turbulence above the destination airport. Moreover, there was a forecast for an adjacent area of convective weather, temperature inversion and wind shear while the weather radar imagery of the area surrounding the accident site around the time of the accident showed areas of light to moderate intensity precipitation.

In other words, the pilot probably should have waited the weather out safely on the ground and not in a holding pattern above his destination airport.

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