Pilot Debrief

LEDER JOHN A LEDER VELOCITY XL RG near Thomson, GA — 2012-07-02

Final reportERA12LA431
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Date
2012-07-02
Location
Thomson, GA, USA
Airport
HQU
Aircraft
LEDER JOHN A LEDER VELOCITY XL RG
Registration
N224SM
Category
Airplane
Highest injury
None
Fatalities
0
Phase of flight
Landing

Probable cause

Separation of the nose landing gear due to a preexisting fatigue crack caused by an earlier shimmy event and the subsequent incorrect installation of the shimmy dampener.

NTSB narrative

The pilot stated that he landed the airplane on the main landing gear and then lowered the nose landing gear on the runway. The nosewheel started to shimmy, and the pilot applied aft pressure on the control yoke; however, the nose landing gear strut assembly subsequently separated from the airplane and the airplane veered right and came to rest in the grass off the right side of the runway. The pilot further stated that he had experienced a shimmy event about 50 flight hours before the accident, and he decided to install a shimmy dampener on the airplane. Metallurgical examination of the components revealed the nose landing gear separated due to a preexisting fatigue crack caused by the earlier shimmy event and the subsequent incorrect installation of the shimmy dampener. Specifically, the shimmy dampener alignment pin had not been installed, which rendered the shimmy dampener ineffective.

Analysis

Primary failure mode
Mechanical failure
First missed decision gate
Pilot could have ensured proper installation of the shimmy dampener before flight.

NTSB coding

Evidence available

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

Docket documents14

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