How Black Box's Discovery Brings Investigators Closer To Reason Behind Air India Crash

New Delhi:

The black box from Air India’s ill-fated Ahmedabad-London flight was recovered from the rooftop of the medical college hostel building it crashed into minutes after take-off on Thursday. Its recovery brings investigators closer to ascertaining the reason behind the crash in which 241 on board the Air India flight and another five people on ground were killed.

What Is A Black Box?

A black consists of two devices – the Flight Data Recorder (FDR) and Cockpit Voice Recorder (CVR). The CVR collects radio transmissions and sounds such as the pilot’s voices and engine noises, according to the National Transportation Safety Board (NTSB)’s website. Investigators can also attempt to track engine noise, stall warnings and other clicks and pops that are recorded. Apart from communication within the cockpit, interaction with the Air Traffic Controller (ATC). This assumes significance as pilots in the AI171 had issued a “Mayday” distress call seconds before plummeting from a height of 625 feet.

The black box comprises two devices – CVR and FDR.
Photo Credit: NDTV

The FDR monitors a plane’s altitude, airspeed and heading, according to the NTSB. Those factors are among at least 88 parameters that newly built planes must monitor. Some can collect the status of more than 1,000 other characteristics, from a wing’s flap position to the smoke alarms. The NTSB said it can generate a computer-animated video reconstruction of the flight from the information collected. the FDR carries 25 hours of information, including prior flights within that time span, which may provide hints about the cause of a mechanical failure on a later flight, per The Associated Press.

Where Is The Black Box Placed And What Does It Look Like?

It is placed in the tail end of the aircraft, which is considered to be a part that is most likely to survive crashes. The black boxes are designed to withstand high impact, fire and deep sea pressure, being made from robust materials like titanium or stainless steel.

In the case of Thursday’s crash, the aircraft’s tail end crashed into the medical college’s hostel building in Ahmedabad. The black box was retrieved from the rooftop of this building.

Contrary to its name, the black box is usually orange or yellow in colour to allow easy visibility.

How Will The Black Box Data Help?

Many questions surround the circumstances that led to the fatal crash of the Boeing 787-8 Dreamliner on Thursday, the first of its kind the aircraft debuted in 2011. Some pertain to what happened in the last 30 seconds of the flight, why the plane was not able to pick up thrust, and if any faults arose with the flaps or engine controls. Details from the black box will also help segregate technical from human fault, apart from giving a clear sequence of events.

Where Will Data Of Crashed Air India Plane Likely Be Retrieved?

Earlier this year, Digital Flight Data Recorder and Cockpit Voice Recorder (DFDR & CVR) Laboratory was inaugurated in Delhi, where retrieved flight data from aircraft can be analysed. The state-of-the-art facility will enable Aircraft Accident Investigation Bureau (AAIB) to repair damaged black boxes, retrieve data, and conduct thorough analyses of accidents and incidents.

Black Boxes Not 100% Reliable

Though largely reliable in finding the root cause behind aviation accidents, black boxes have also known to present its limitations. A Jeju Air plane flying from Bangkok to South Korea with 181 people on board crashed on landing Sunday, killing 179 people on board. It black box was recovered, but analysis by the NTSB found that crucial data from the last few minutes of the flight was wiped out.

In the case of the notorious downing and disappearance of the Malaysia Airlines Flight 370 in March 2014, the signals that would emanate from the black box were not detected during search operations.