Flightcrew have welcomed close operational surveillance for many years. Why, then, would a crew erase a CVR?

Airline pilots have the most closely monitored profession in the world. If people in any other job were faced with the introduction of surveillance at the same level, their professional association or union would resist it – as pilots’ organisations did when cockpit voice recorders (CVR) and flight data recorders (FDR) were first proposed.

But now, and for more than three decades, those taking up flying as a career have known that, at the very least, the performance and operation of the aircraft they fly would be measured and recorded, as would all their speech, communications and the sounds audible in their “office”. Nobody objects any more, because the benefits to aviation have been demonstrated so many times – as has the disadvantage of low-performance recorders that have proved unable to illuminate the causes of some more complex accidents. Checks and balances to prevent the abuse of information by the airline or the authorities have been agreed between pilot associations and airlines, the regulators and, in many countries, the law. No pilot voices have complained that monitoring is undesirable.

In the last decade most of the world’s major airlines have gone a step further down the pilot-surveillance road and adopted flight data monitoring. This process involves downloading quick-access recorders or today’s more-capable digital FDRs (DFDR) at the end of each flight to check whether any operational anomalies occurred during it. Monitoring might have been seen by the pilots as the most personally invasive check of all – every action they perform is checked against a set of parameters to see whether they exceeded what has been deemed acceptable. In the event, it has proven to be acceptable to most pilots, and is even liked by many of them. The clear benefit is that pilots who unintentionally make excursions outside the approved operational envelope can have their recurrent training appropriately tailored. A side-effect of monitoring that has proven unexpectedly useful is that let-down or approach procedures that are difficult to fly have been revealed as such, and some have been redesigned. Everyone benefits, especially flight safety.

Waiting in the wings is another cockpit-surveillance measure that the US National Transportation Safety Board includes on its list of “most-wanted safety improvements”: flightdeck video surveillance. The NTSB says cockpit video surveillance would “give investigators more information to solve complex accidents”. But no national aviation authorities, despite the board’s convictions, seem to be in a rush to do this. Not only do US pilot unions argue against it, but the adoption of yet another form of surveillance has to be justified in terms of its contribution to safety. At present the thinking is that the situations in which video might provide answers that modern CVRs and DFDRs would not are rare.

Such accidents are normally the ones in which “human factors” play a large part. Human factors originate in people’s heads, and a camera will not illuminate rationales for action or lack of it. What a pilot did is usually available from a DFDR or CVR. If the issue is which pilot did it, that is not crucial because accident investigation is not about blame or legal prosecution, it is about reducing the chances of a repeat. Or that, at least, is what the International Civil Aviation Organisation says. So the case for cockpit cameras has not yet proven strong enough to persuade the aviation community that they are, on balance, a sufficient potential contributor to safety.

Pilots, then, are happy to undergo surveillance if it will benefit aviation. So why would a pilot tamper with the surveillance equipment? It is a well-known phenomenon that a culture of allocating blame, together with national laws that call for criminal prosecution of pilots even before the accident investigators have gathered all the facts, are often the cause of pilot failure to file reports on risk-bearing occurrences that they survived. Hong Kong does not have such legal practice nor, traditionally, its airlines such a culture, but is this situation subtly changing? Before condemning the Dragonair pilots who are said to have erased a CVR, it would be worth examining why they had the motivation to take an action that was against airline procedures and commonsense.

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Source: Flight International