Flight Data Recording Questions and Answers

Answer: A

Correct answer: Both Statement I and Statement II are correct

Both are true and the second is the reason for the first. A memory module recovered from an accident may be cracked, contaminated or soaked in salt water.

Applying power to a wet or damaged module can short tracks, drive corrosion electrochemically, or destroy cells that would otherwise have been readable - and there is no second attempt. The module is therefore examined, cleaned and dried before any electrical connection, and the memory chips are read directly if the interface is damaged.

Answer: B

Correct answer: Statement I is correct but Statement II is incorrect

The first statement is sound: recorded data is validated against independently known events - radar returns, radio recordings, the times of documented actions - before conclusions are drawn from it.

The second is the reason validation is needed rather than a fact. A misapplied conversion factor often produces a trace that looks entirely plausible: a gain error scales a parameter without distorting its shape, and an offset shifts it. It is precisely because such errors are not obvious that external corroboration is required.

Answer: C

The acquisition unit sits between the aircraft and the recorder, so a fault there loses parameters while the recorder itself remains serviceable. The frame layout is what ties a word position to a particular parameter.

Answer: D

Correct answer: 1, 2, 3, 4, 5

The order is one of increasing risk to the evidence. The unit is located, using the beacon underwater, and recovered with its condition and position documented - both of which may matter later.

The memory module is then assessed before any power is applied, since an electrical connection to a damaged or wet module can destroy what survives. Cleaning and drying follow, and only then the readout and its validation against known events. Every step before the readout exists to protect the one chance of reading it.

Answer: A

Correct answer: 1, 2, 3, 4

The sequence follows the storage medium. The earliest recorders engraved a stylus trace onto metal foil or wire, capturing a handful of parameters.

Magnetic tape followed, allowing far more parameters but bringing a transport mechanism that was vulnerable to impact and fire. Solid-state memory replaced it, with no moving parts and effectively unlimited capacity. The extension of voice retention to 25 hours came later still, made possible by that capacity and driven by investigations that found the earlier periods too short.

Answer: B

Correct answer: 1, 2, 3, 4, 5

The order is the working cycle of such a programme. Data is downloaded routinely from the quick access recorder, and software detects exceedance events automatically against defined thresholds.

De-identification comes before analysis, so that trends are examined without reference to individuals. Analysis across many flights is what turns isolated events into a signal, and the output is a change to procedures or training. The last step is what makes the programme worth running; measurement afterwards shows whether it worked.

Answer: C

Correct answer: 1, 2, 3, 4, 5

The standard applies the tests in a defined order on the same unit, and the order is deliberate: each test leaves the module in the condition the next begins with.

Impact shock comes first, then pin penetration under a dropped weight, then static crush representing wreckage resting on it. The fire tests follow - a high-intensity flame and then a prolonged low-intensity one - and deep-sea immersion under pressure comes last. Passing them singly is not enough; the module must survive the sequence.

Answer: D

Correct answer: Only three

The first three are correctly matched: the data recorder holds parameters over a long period, the voice recorder holds speech, radio calls and ambient sound, and the underwater locator beacon emits an acoustic pulse for underwater search.

The fourth is wrong on the essential point. A quick access recorder is not crash protected - it sits in an ordinary enclosure and exists for routine flight data monitoring, which is exactly why it is easy to download.

Answer: A

Correct answer: Only three

The first three are right. The underwater locator beacon transmits at 37.5 kHz, the older emergency locator transmitter frequency is 121.5 MHz, and 406 MHz is the satellite-detected distress frequency.

The fourth is wrong: 8.33 kHz is the channel spacing used in VHF air-band radio, a matter of how the aeronautical spectrum is divided, and has nothing to do with underwater acoustics. Note the three orders of magnitude separating the acoustic frequency from the radio ones.

Answer: B

Correct answer: Only three

The first three pair each test with what it represents: impact shock stands for the deceleration of the crash, static crush for wreckage resting on the unit, and the fire test for a post-crash fuel fire.

The fourth understates the immersion test badly. It represents submersion in deep water at the pressure of considerable depth, held for a long period - the condition of a recorder on the sea bed, not rain on a ramp, which any avionics box must tolerate as a matter of course.