Anatomy Of An Aircraft Accident Investigation

Flying Safety, Jan, 2001 by Kurt J. Saladana

It's a Friday morning about 1000 and you're in an engine bay doing a teardown. The exterior hangar door is open to let the air circulate and take the edge off of the 110-degree ambient temperature. In the distance, you hear sirens. Curious, and ready for a break, you walk outside and look north, towards the direction the sirens seem to be heading. At first you don't see anything. Then, off to the west, you see a black cloud. Two thoughts cross your mind: "I hope nobody got hurt!" and "Please don't be an engine I worked on." Seconds later one of your buddies is at the hangar bay door. He confirms an aircraft is down, but doesn't know if the pilot got out or if the aircraft hit anything on the ground.

You go back to work, but it's hard to concentrate. A little while later, your buddy reappears and gives you the news you had been dreading--the pilot didn't survive. However, the aircraft did hit the ground in an uninhabited location, so no one else was injured. The current rumor--the first of many--is that the aircraft lost its engine shortly after takeoff. Your mind races as you think of every engine you worked on in the last few weeks, and you start playing the "What if" game with all of your recent actions. Then, another question forms in your mind: "What happens now?"

Initial Actions

This scenario plays itself out routinely in various iterations throughout the USAF on an annual basis. So, what does happen after an aircraft crash? In a case like this one, the control tower is likely the first agency to know about the crash and immediately calls the Command Post (CP), where the Disaster Response Plan would be initiated. In addition to notifying the wing/base commander, the CP notifies firefighters, emergency medical personnel and security forces. At the same time, local air traffic controllers transmit a message alerting all aircraft in the vicinity about the mishap. This not only gives notice to rescue resources who may be able to provide assistance--but also keeps "rubberneckers" out of the way. It isn't all that unusual for a police or media helicopter to be first on the scene and transport the pilot to the closest medical facility. The Disaster Response Force joins any emergency response personnel already on site and works to:

* Prevent further injury and damage by extinguishing any fires;

* Safe the site by identifying, and removing or neutralizing, hazards like unexploded ordnance, or equipment under pressure or tension; and

* Secure the site against intrusion by media, sightseers or souvenir hunters. This prevents them from hampering the accident investigation or getting hurt.

Upon notification of the accident, units involved will gather and secure training records and aircraft maintenance/servicing records for pilot(s), maintainers and the affected aircraft. Within hours of the accident, the wing/installation commander appoints an Interim Safety Board, whose members' sole responsibility is to preserve evidence for the MAJCOM-appointed "permanent" Safety Investigation Board (SIB). This evidence preservation includes collecting training records and maintenance records, gathering witness statements and obtaining perishable fluid samples. The "fluid samples" include not only oil, hydraulic and fuel samples from the aircraft and associated support and servicing equipment, but also blood and urine samples from the aircrew and anyone who may have worked on the aircraft or its components. This is standard procedure so, as the engine mechanic in this scenario, you shouldn't be surprised if the doctor from the Interim Safety Board calls to arrange for samples.

Safety Investigation Board (SIB) Composition

Within one to three days of the accident, the SIB will arrive and take command of the investigation and crash site. SIB members include:

* A Board President (Colonel or Brigadier General pilot or navigator);

* An Investigating Officer (pilot or navigator who has completed the HQ Air Force Safety Center's [HQ AFSC] Flight Safety Officer or Aircraft Mishap Investigation Courses);

* A HQ AFSC Representative (pilot, navigator or maintenance officer whose primary duty is the investigation of aircraft mishaps);

* A Pilot Member (someone current and qualified on the type of aircraft involved in the mishap);

* A Maintenance Officer;

* A Flight Surgeon;

* A Life Support member, qualified to analyze egress systems and life support equipment; and

* A Recorder, the administrator for the SIB team.

By regulation, the SIB has thirty days to investigate the mishap, determine the cause (or causes) and formulate recommendations to prevent future, similar accidents. By the end of the allotted time, the SIB must also:

* Publish a formal report containing all of the deliberations and substantiating material that led to its conclusions;

* Compose a final message summarizing the formal report; and

* Prepare a briefing for the MAJCOM commander and his/her senior staff, explaining why the mishap occurred, how the SIB reached its conclusions and how the SIB believes the USAF can prevent the same thing from happening again.