Air India Plane Crash: How Did the Black Box Withstand 1,000°C Temperature?

Two days after Air India flight AI-171 crashed in Ahmedabad, Civil Aviation Minister Kinjarapu Ram Mohan Naidu confirmed that the black box has been recovered. As per latest reports, over 270 people, including 241 on board the flight, were killed in the tragedy. The aircraft, loaded with 1.25 lakh litres of fuel, burst into a fireball as it crashed into the complex of BJ Medical College, raising the temperature to 1,000 ⁰C. Even birds did not have the time to escape. How could the black box survive such a high-impact accident?

What is the Black Box?
The black box is a critical tool in determining the cause of aviation accidents. It includes two components: the Flight Data Recorder (FDR) and the Cockpit Voice Recorder (CVR). The FDR captures hundreds of flight parameters such as altitude, speed, engine performance, heading, and control inputs. The CVR records cockpit conversations, radio communications, alarms, and ambient sounds like engine noise and switch clicks, all of which are vital for understanding the sequence of events and crew responses.

Despite its name, the black box is painted bright orange for visibility. It plays a central role in aviation investigations and is designed to withstand extreme conditions including high-impact crashes and fires.

What is a Black Box Made Of?
Black boxes are built to survive severe conditions. They are typically made from titanium or stainless steel and can endure impact forces up to 3,400 g, temperatures as high as 1,100°C for up to an hour, and water pressure at depths of 20,000 feet. The internal components are shielded with layers of silica-based materials, ceramic tiles, or heat-resistant foams. Memory chips are housed in shock-absorbing casings to preserve recorded data even in catastrophic events. An underwater locator beacon, made of corrosion-resistant materials, is attached and can emit an acoustic signal for up to 30 days if submerged.

Where is the Black Box Located?
The black box is usually installed in the tail section of the aircraft, which statistically suffers less damage in crashes. This location improves its chances of surviving an impact and being recovered. It is mounted in a reinforced, fireproof compartment and is connected to the aircraft’s key systems, including cockpit microphones, flight instruments, and engine sensors.

Cost of a Black Box
According to the Pilot Institute, a black box weighs approximately 4.5 kilograms and costs between $10,000 and $15,000.