How the NTSB Investigates Fatal Plane Crashes: A Comprehensive Guide

When a fatal plane crash occurs, the National Transportation Safety Board (NTSB) is tasked with determining the probable cause of the accident. This critical process begins with the arrival at the crash site, regardless of the time, and involves meticulous examination and documentation of every detail. In this article, we will delve into the methods and procedures used by the NTSB to gather evidence in accident investigations.

Initial Response and Evidence Collection

The NTSB begins its investigation as soon as possible. Typically, first responders have secured the area, and insured light aircraft are secured and removed to a hangar for the NTSB. Before the aircraft is moved, the NTSB thoroughly documents the scene with photographs of the plane, the surrounding area, and any tree strikes. The team focuses on identifying the 'four corners' of the plane: the nose, tail, and both wings. This helps determine if the crash occurred in the air or upon impact with the ground.

Examining the Debris Field

The NTSB supervisor is the first to examine the wreckage. She or he will locate the 'four corners' of the aircraft on the ground and gather further details. Ground technicians methodically document the site, looking for specific clues such as:

Explosions indicated by outward curling metal Signs of burns caused by explosions or fire Evidence of metal fatigue that occurred during flight Whether parts have dirt or grass attached, which suggests they broke off during the crash The path of the parts from the plane to the ground, which reveals the sequence of events Paint scratches on both planes in dual-aircraft crashes to determine impact direction Contaminants on engine props (twisted vs. bent), indicating whether the engine was running upon impact Cable continuity for light planes to ensure proper operation of ailerons and rudder Location and status of black boxes (CVR, GPS), which are retrieved as soon as possible

Other critical data includes:

Interviews with witnesses and families to understand the pilots' behaviors and temperaments Data recorder content and any contact with air traffic control (ATC) while the plane was on radar Interviews with first responders involved in body removal and other crucial actions Closer examination of maintenance logs to uncover potential issues

Analyzing Evidence to Determine Probable Cause

The NTSB team meticulously assembles all collected evidence to piece together the probable cause of the accident. For instance, if a fatal crash is suspected of having a carbon monoxide leak, the team will examine the flight data recorders (FDR) and cockpit voice recorders (CVR) for any mentions of such issues. Specific components like the jackscrew and tail assembly are investigated to find the source of the problem. They might ask aircraft manufacturers to contribute specialized expertise, and all findings are reported back to the IIC (Inspector in Charge).

Sending Recommendations to the FAA

Upon determining the probable cause, the NTSB compiles the findings and recommendations. These reports are sent to relevant entities, such as the Federal Aviation Administration (FAA), for implementation. For example, in a carbon monoxide-related crash, the investigation led to the discovery of missing bolts on the manifold, which were subsequently checked across all fleets. This prompted the FAA to issue safety recommendations and ensure adequate carbon monoxide monitoring systems are installed.

In conclusion, the NTSB's rigorous investigation process ensures that every aspect of a plane crash is thoroughly examined to prevent future incidents and improve airline safety. The findings and recommendations from these investigations play a pivotal role in maintaining public trust and enhancing aviation safety standards.