On the surface the extraordinary Q400 larceny at Seattle might inevitably seem to be a prelude to new security countermeasures. But it only seems that way.

Because US investigators, three days later, were picking over the debris of another twin-engined aircraft, a Cessna executive jet, flown into the ground in Utah by a suicidal man at the controls – the sole occupant and, by chance, the sole fatality. Not an unlicensed baggage-handler but an experienced and authorised pilot.

Strip away the spectacular aerobatics and the pursuit by fighters, all captured on video, and the two threads become inextricably entwined: aircraft accessed by trusted personnel with haunted minds.

Neither was a straightforward case of grand theft aero. Aircraft have been stolen for almost as long as they have existed, whether misappropriated by criminals for their value or by drunks for a joyride.

The word ‘suicide’ turns up in more than 80 incidents listed by the US National Transportation Safety Board alone. Not all specifically involve pilots using their aircraft to take a deliberate, final flight, but a dishearteningly-large number of them do. Hardly any of which attract attention, as long as there are no collateral casualties, no disruptive consequences, and no mobile phone footage uploaded to YouTube.

When the highly-public destruction of a Germanwings Airbus in the French Alps triggered a crisis of confidence over the mental health of professionals in the cockpit, the air transport industry responded with a cocktail of evocative statements and half-baked countermeasures. Because it could not offer much else.

Peer intervention is effective, but relies on detecting mental illness in a male-dominated, fault-intolerant business, with its image of coolness under pressure. It amounts to hunting invisible, possessive spectres capable of passing unseen from person to person, with such stealth that even the individual affected might not recognise their own affliction.

But it is all the industry has. Even if security measures, post-Seattle, could limit ground workers’ access to a company’s aircraft, they could not stop anyone flying his own.

“He never took chances. Everything was by the book,” said the president of the Utah firm which employed the ill-fated Cessna jet’s pilot, succinctly summarising aviation’s quandary. “It all boils to trust. I don’t know what we would have done different.”

Source: Flight International