Part 5/8:
During the aircraft's maintenance, details emerged about the inspection protocols. Mechanics were working on de-icing boots, requiring the removal of parts from the horizontal stabilizer. While the assembly was partially disassembled, the upper screws—crucial for stability—had been removed from the left leading edge but not replaced. This was accomplished in a dimly lit area outside the hangar, further complicating the situation.
The lack of proper communication between successive shifts led to a breakdown of protocol. The NTSB determined that not only the mechanics but also supervisors and inspectors failed to adhere to necessary procedures, creating an environment of negligence concerning safety.