Pilot Debrief

CESSNA 182S near Springfield, IL — 2014-12-10

Final reportCEN15IA076
Sign in to save
Date
2014-12-10
Location
Springfield, IL, USA
Aircraft
CESSNA 182S
Registration
N661SP
Category
Airplane
Highest injury
None
Fatalities
0
Phase of flight
Maneuvering

Probable cause

The improper installation of a doubler patch, which prevented the right flap from actuating and moving properly and led to the subsequent interference with the aileron.

NTSB narrative

During a proficiency flight for one of the pilots, he was demonstrating a slow-flight recovery procedure, and he added power and began retracting the flaps. When the flaps passed through 10 degrees toward fully retracted, the pilot felt an uncommanded right yoke control movement. As the pilot applied more pressure to the control yoke to maintain level flight, both pilots heard a loud pop, and the uncommanded right yoke control movement stopped. The pilots assessed the airplane and noted that the right flap was buckled. They then conducted a precautionary landing without incident. A postaccident examination of the airplane found that the inboard portion of the right flap had become dislodged from its track and that the flap had shifted outboard and contacted the aileron. Further examination of the flap system found that a doubler patch had been improperly installed on the lower trailing edge skin; the improper installation altered the curvature of the lower trailing edge skin and infringed on the normal actuation of the flap rollers. Both the inboard and outboard brackets surrounding the flap track had fractured due to the repeated stress applied during the flap roller actuation. A review of the public agency's fleet of airplanes found similar curvature of the lower trailing edge skin and bracket damage due to the improper installation of doubler patches.

Analysis

Primary failure mode
Mechanical failure
First missed decision gate
Pilot could have inspected flap system before flight to prevent malfunction.

NTSB coding

  • Flight control sys malf/fail · Maneuvering

Evidence available

  • Photos
  • 4 docket documents
View NTSB final reportView NTSB docket

Docket documents4

Related mishaps