Which of the following statements with regard to Black Boxes used in modern aircrafts is/are correct ? 1. They carry a beacon emitting red light pulses to facilitate underwater detection. 2. They record both the cockpit voice and flight data. 3. Their memory units are made using either stainless steel or titanium. Select the answer using the code given below :

QUESTION

Medium

Science & Technology

Prelims 2026

Which of the following statements with regard to Black Boxes used in modern aircrafts is/are correct ?

They carry a beacon emitting red light pulses to facilitate underwater detection.
They record both the cockpit voice and flight data.
Their memory units are made using either stainless steel or titanium.

Select the answer using the code given below :

Select an option to attempt

Explanation

Statement 1 is Incorrect: Black boxes are equipped with an Underwater Locator Beacon (ULB). When immersed in water, the ULB activates and emits an acoustic (ultrasonic) pulse (typically at 37.5 kHz) to guide sonar-equipped searchers. It does not emit light pulses, as light cannot travel effectively through deep ocean water.

Statement 2 is Correct: The term "black box" collectively refers to two distinct recording devices (which are sometimes combined into a single unit): the Cockpit Voice Recorder (CVR), which records radio transmissions and sounds in the cockpit, and the Flight Data Recorder (FDR), which records technical flight parameters such as altitude, airspeed, heading, and acceleration.

Statement 3 is Correct: The data is stored inside a highly protected component called the Crash-Survivable Memory Unit (CSMU). To survive extreme impact (up to 3,400 Gs), deep-sea pressure, and intense fire (up to 1,100°C), the CSMU's outer armor is manufactured using heavy-duty stainless steel or titanium, layered with thermal insulation.

Therefore, option B is the correct answer.

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