Loss of Control in Flight · NTSB WPR17FA200

RAYTHEON AIRCRAFT COMPANY G36 — Benicia, CA

2 fatal
DateSeptember 9, 2017
LocationBenicia, CA
AircraftRAYTHEON AIRCRAFT COMPANY G36
Purpose of flightPersonal
ConditionsDay · Visual Meteorological Cond
Phase / occurrenceUncontrolled descent Collision with terr/obj (non-CFIT)
Pilot age67
Pilot total time528 hrs · Building experience
Time in type3 hrs
Fatalities2

Probable cause

The pilot's failure to maintain adequate airspeed which caused the airplane to exceed its critical angle of attack and led to an aerodynamic stall.

NTSB findings

  • Personnel issues-Task performance-Use of equip/info-Aircraft control-Pilot - C
  • Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Airspeed-Not attained/maintained - C
  • Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Angle of attack-Not attained/maintained - C
  • Personnel issues-Experience/knowledge-Experience/qualifications-Total experience w/ equipment-Pilot

What happened

The private pilot and passenger departed for a personal cross-country flight. Radar data indicated that the flight track after takeoff was consistent with the course to the destination airport. During the first few minutes of flight, the radar data indicated that the airplane was in a climb. However, during the last 2 minutes of flight, as the airplane neared its level-off altitude, the airplane's speed had decreased and was approaching the stall speed, which was between 68 and 73 knots, depending on the airplane's bank. The calibrated airspeed was calculated to be about 62 knots at the last radar return. At that time, the airplane had entered a right turn and was rapidly descending. The airplane impacted terrain about 9 miles from the departure airport.

Postaccident examination of the airframe and engine revealed no anomalies that would have precluded normal operation. Signatures at the accident site and the damage to the airplane indicated a near vertical impact, which was consistent with an aerodynamic stall.

An editorial "what led to it / how to avoid it" analysis for this accident is generated separately and will appear here.

View the official NTSB docket →