Bombardier Inc DHC-8-202 N367PH accident near Sterling, Virginia

Probable cause

Undetermined.

NTSB analysis

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.

Text from the NTSB. Open the NTSB docket for ERA09LA529 for the full record.