OPINION: What accident statistics don't tell us

With 2015 having proven – at least conditionally – to be the safest year on record for airline passenger transport operations, the inquiry into the Tatarstan 737 crash at Kazanis a reminder that such statistics are, to some extent, still dependent on good fortune.

Investigators frequently use the ‘Swiss cheese’ model to illustrate the manner in which weak elements can line up to cause an accident. But when the nature of an airline’s operation turns out to have been more hole than cheese, this model becomes practically redundant.

If the revelation that a carrier’s pilots can find themselves attempting to correct a gross position error on approach before catastrophically bodging a go-around after failing to understand their aircraft’s behaviour isn’t sufficiently disturbing, the extraordinary attempt to deflect attention by suggesting a possible mechanical problem, despite the lack of evidence, might be.

The mystery of this accident is less about why it happened than why it had not occurred sooner.

But had the crew at Kazan managed to recover the aircraft, the incident would have been ignored by statistics that focus on hull losses and casualties.

Which is why the improvement in safety figures for 2015 ought to be viewed in an honest context. The absence of an aluminium shower, while infinitely preferable to the alternative, is not the truest mark of a safe air transport system.