BOMBARDIER INC DHC-8-202 near Sterling, VA — 2009-08-29

Probable cause

Undetermined.

NTSB narrative

On an unknown date and at an unknown time, the airplane sustained substantial damage to the bottom of the fuselage tail section. The damage was found during a maintenance C-check inspection on August 29, 2009. The damage was found when maintenance personnel were inspecting the inside of the tail section and noticed bowing and bending in the support structure and damage to nearby rivets. The damage was consistent with tail strike damage and had resulted in a puncture of the pressure vessel of the airplane. According to the maintenance task cards for different inspections of the airplane, an exterior inspection was to be completed prior to any other work. At least three exterior inspections were completed within the weeks preceding the discovery of the damage, including the inspection in which the damage was discovered. Each inspection required examination of the damaged area. Because maintenance personnel likely missed the damage during these inspections, pilots performing preflight checks of the airplane would be just as likely to miss the damage. Due to the height of the damage personnel would likely need to bend down in order to see it.

Analysis

Primary failure mode

Mechanical failure

First missed decision gate

Preflight inspection procedures not adequately followed to check for tail strike damage.

NTSB coding

• Abnormal runway contact · Unknown

Evidence available

• FDR / data
• 9 docket documents

Docket documents9

• Flight Data Recorder Data For Landingsfdr
• Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 - Operatorform
• Statement of Party Representatives to NTSB Investigation - ALPAinterview
• Statement of Party Representatives to NTSB Investigation - Operatorinterview
• Airplane Operator Manual [Excerpt]other
• Heavy Maintenance Task Card [Excerpts]other
• Mainteance Line Check Task Card [Excerpts]other
• Memorandum Of Record [Email Excerpt Bombardier]other
• Operator Submissionother