Correct Option
The correct option is 2 and 3 only.
[as per provisional answerkey]Explanation
A Black Box, technically known as a Flight Recorder, is a critical electronic recording device placed in an aircraft to facilitate the investigation of aviation accidents and incidents. Despite the name, these devices are painted bright orange to aid visibility.
- Statement 1 is Incorrect: Black Boxes do not emit red light pulses for underwater detection. Instead, they are equipped with an Underwater Locator Beacon (ULB) that emits ultrasonic acoustic pulses (pings) when the sensor touches water. These signals are detectable by sonar and acoustical hydrophones rather than visual light pulses, which have limited range in deep or murky water.
- Statement 2 is Correct: Modern aircraft are required to carry two types of flight recorders: the Flight Data Recorder (FDR), which logs specific aircraft performance parameters (such as airspeed, altitude, and fuel flow), and the Cockpit Voice Recorder (CVR), which records the audio environment of the flight deck, including crew conversations and radio communications.
- Statement 3 is Correct: To survive extreme impact, intense heat, and high deep-sea pressure, the Crash Survivable Memory Unit (CSMU) is encased in a multi-layered protective shell. The outermost housing is typically constructed from high-strength stainless steel or titanium, supplemented by high-temperature insulation to protect the solid-state memory chips.
Key Takeaway: Black Boxes utilize ultrasonic acoustic beacons for underwater recovery and are encased in high-strength metals like titanium or stainless steel to protect both flight data and cockpit voice recordings.