WHAT’S INSIDE?

Black boxes contain vital devices encased in protective layers

7 CRASH-RESISTANT HOUSING

The steel casing is built to withstand an impact 3,400 times the force of gravity.

8 MEMORY BOARD

A black box’s memory boards can store 25 hours of flight data.

6 UNDERWATER LOCATOR BEACON

When this device is submerged in water, it releases ultrasonic pulses every second for 30 days to alert search and rescue teams.

5 THERMAL BLOCK

A thick layer of paraffin surrounds the memory board. In high temperatures this melts and absorbs heat to keep the memory board cool.

1 POWER SUPPLY

The batteries inside can provide power to the box for 30 days after a crash.

2 VOICE RECORDER

Two hours of voice recordings can be stored on the device to relay any conversations in the cockpit immediately before a crash.

3 CONTROLLER BOARD

Circuit boards in the base process data from up to 3,000 parameters.

4 INSULATION

Components are insulated to withstand temperatures of 1,110 degrees Celsius.