Loss of Control in Flight · NTSB WPR17FA139

NORTH WING UUM INC SPORT X2 912 — Chelan, WA

2 fatal High-time pilot
DateJuly 1, 2017
LocationChelan, WA
AircraftNORTH WING UUM INC SPORT X2 912
Purpose of flightPersonal
ConditionsDay · Visual Meteorological Cond
Phase / occurrenceUncontrolled descent Collision with terr/obj (non-CFIT)
Pilot age70
Pilot total time6,000 hrs · High time
Time in type3,013 hrs
Fatalities2

Probable cause

The flight instructor's failure to maintain control of the aircraft while demonstrating a spiral dive, which resulted in a loss of control. Contributing to the accident was the instructor's decision to demonstrate a spiral dive maneuver at an altitude that was too low for recovery.

NTSB findings

  • Personnel issues-Task performance-Use of equip/info-Aircraft control-Pilot - C
  • Aircraft-Aircraft oper/perf/capability-Performance/control parameters-(general)-Not attained/maintained - C
  • Personnel issues-Action/decision-Info processing/decision-Decision making/judgment-Pilot - F
  • Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Altitude-Not attained/maintained - F
  • Environmental issues-Physical environment-Terrain-Mountainous/hilly terrain-Ability to respond/compensate

What happened

The flight instructor and the student pilot were conducting a local flight in the weight-shift-control aircraft. An onboard camera captured the accident flight and showed that, at the time of the accident, the instructor was demonstrating a spiral dive maneuver. The video showed that the maneuver was initiated at an altitude that appears to be below 1,000 ft AGL which is a minimum required recovery altitude. During the maneuver, the aircraft's bank angle continued to increase until the aircraft entered a nearly-vertical descent and impacted terrain. Postaccident examination of the wreckage revealed no evidence of a preimpact mechanical malfunction or failure that would have precluded normal operation.

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 →