After reading a few of the plane crash threads on this site, it occurred to me that a lot of people don’t know how crashes are investigated or what
the process is, which ultimately leaves them confused when trying to wade through the multitude of information put out by reporters. I saw an
opportunity to educate fellow ATSers and potentially prevent some of this confusion in the future. Hopefully the background info and hypothetical case
study will do just that. This write up will deal mainly with the stereotypical airliner crash, not a more common general aviation airplane crash.
It is important to understand that the sequence leading up to an airplane crash is almost guaranteed to be long and have multiple steps. An airplane
almost never goes down because of one thing- it is always a chain of events that leads to an airplane crashing. The exception being something like a
bomb being planted in the airplane.
Once an airplane goes down, the investigation begins. Who actually does the investigation varies on where the crash took place. Crashes in the US will
be investigated by the National Transportation and Safety Board (NTSB). Crashes in Japan are investigated by the Japan Transport Safety Board (JTSB).
The UK has their Air Accidents Investigation Branch (AAIB). Most major countries have their own investigation boards. However, the NTSB is largely
considered to be the go-to agency for expert analysis, and many countries will often request the assistance of the NTSB for crashes in their own
countries. We will use the NTSB for this write-up.
As soon as the crash is reported to the NTSB, agents are on their way. Investigator teams, called “go teams”, are on call 24/7 to be launched
anywhere in the country/world at a moment’s notice once requested.
Once arriving, the first order of business (and usually at least partly taken care of by local authorities) is to search for survivors. Agents will
coordinate with rescue teams in the area to search for any possible survivors. They will also coordinate with local law enforcement to secure the
crash site. This is different depending on where the crash site is. If on land, securing and searching for survivors is relatively easy when compared
to a crash in the ocean. An oceanic crash site will usually require a larger search and rescue effort. During all of this, the investigators will also
have to interact with the media as well, to varying degrees.
After providing aid to any possible survivors and securing the crash site, investigators will begin to comb over the crash site. Everything is
documented like it is a crime scene. Photos and videos are taken to be used in the future. Eyewitness accounts are also taken during this time.
Wreckage is examined and analyzed to wring out any clues that it can provide. If investigators think that a certain piece may be especially vital in
the accident chain, they may send it off to subject matter experts who examine it further and see if the piece of wreckage broke or malfunctioned in a
way that would contribute to a crash. If necessary, investigators will take all the wreckage and “re-build” the aircraft in a hangar in an attempt
to hunt down where the malfunction originated.
Many people are aware of the fabled “black boxes” that all airliner-type airplanes are equipped with. They are the Cockpit Voice Recorder and the
Flight Data recorder. These two pieces of equipment paint an invaluable picture of the accident for investigators. They give a glimpse into the
thoughts and performance of the crew, as well as allow investigators to create a visual of the airplane before it crashed (see
for video made from an FDR). As seen with AF447 and MH370, finding these boxes can be
highly difficult in oceanic crash site investigations.
After bringing all this information together, investigators will figure out a list of causes for the crash. There are a very long list of potential
causes for an airplane crash, but some of the most common are:
1. Poor Crew Resource Management- Crews that don’t communicate, identify the problem, fly the airplane, and take care of the problem all at the same
time usually don’t fare too well.
2. Mechanical Failure- Pretty self-explanatory. Sometimes this is a result of the airline’s own maintenance, and sometimes it is a result of a
problem that didn’t get worked out in the testing of the aircraft.
3. Pilot error- Self explanatory.
4. Fatigue- A growing concern in the last few years has been the fatigue levels of flight crews. There is proven science that a higher level of
fatigue leaders to a higher chance of fatal mistakes in the cockpit.
Finally, the investigation team will compile a report and render their final verdict. The report consists of an impartial narrative of the flight up
until the moment of impact. It also includes things like weather, pilot biographies, and any information from the airline’s flight crew manuals.
After rendering their final verdict, the investigation team will also recommend changes if necessary. For example, they can recommend that the 737-800
fleet’s radar altimeter be replaced immediately or that new pitot tubes be installed on all A330 aircraft. It is up to agencies like the FAA to take
these recommendations, weigh them, and then decide whether or not to require operators to comply with them by issuing an Airworthiness Directive.
You can search the database of NTSB crash reports here
edit on 7-1-2015 by justwanttofly because: (no reason given)