Pilot Debrief

CESSNA 150F near Bullard, TX — 2017-08-01

Final reportCEN17LA298
Sign in to save
Date
2017-08-01
Location
Bullard, TX, USA
Airport
6X0
Aircraft
CESSNA 150F
Registration
N8879S
Category
Airplane
Highest injury
Serious
Fatalities
0
Phase of flight
Initial climb

Probable cause

The partial loss of engine power due to carburetor icing and the pilot's inability to maintain adequate airspeed during the soft-field takeoff, which resulted in an exceedance of the airplane's critical angle-of-attack and an aerodynamic stall.

NTSB narrative

Following a full-stop landing and a back taxi to the runway, the flight instructor and a student pilot planned to conduct a soft-field takeoff to prepare the student for his private pilot test flight. Although there were no witnesses to the takeoff, an automobile dash camera video showed the airplane flying just above tree tops and then entering a right turn. During the turn, the left wing and the nose of the airplane dropped, which was consistent with a stall and an initial spin. The airplane then descended and impacted the ground. The available evidence did not indicate which pilot was flying the airplane at the time of the accident, but it is likely that the student pilot was flying at the time. Postaccident examination of the airplane and engine revealed no anomalies that would have precluded normal operation. The carburetor heat control was found in the off position, which was the correct position for takeoff. The temperature and dew point at the time of the accident were in a range of susceptibility for moderate icing at cruise power settings and serious icing at descent power settings. Although the airplane was at takeoff power when the accident occurred, a partial loss of engine power likely occurred due to carburetor icing, which might have accumulated while the airplane was operating at a lower power setting on the ground before the accident takeoff. The partial loss of engine power resulted in reduced airplane performance and the pilot's inability to maintain adequate airspeed, which then resulted in an exceedance of the airplane's critical angle-of-attack and a subsequent aerodynamic stall.

Analysis

Primary failure mode
Loss of control
First missed decision gate
Instructor could have ensured full flap retraction before takeoff.

NTSB coding

Evidence available

  • Video
  • 6 docket documents
View NTSB final reportView NTSB docket

Docket documents6

Related mishaps