Monday, March 30, 2015

Tragic Crash of the Germanwings Flight 9525: Human and Socio-Economic-Technical Factors

Initial investigations have revealed that the co-pilot intentionally brought down Germanwings Flight 9525 by locking himself inside the cockpit; with the chief pilot locked out and unable to gain entry.

French Red Cross Members Pay Tribute to the Victims of Germanwings Flight 9525 (Photo Credit: CNN)
On first blush, the obvious cause would be attributed to the co-pilot, the man on the "tactical-edge" -- at the controls. However, it is equally, if not more important, to also consider the latent and hidden failures that could be attributed to the "Organization." How was such a pilot allowed at the controls in the first place? That is a Latent / Organizational failure. The plausible reasons for this:
(1) Insufficient funds and time to conduct training, psychological tests and screening.
2) Low supply of high quality pilots who require a higher salary; so settle for marginal or substandard pilots or personnel (?)
3) Throughput pressures due to financial stressors causing a pilot "Burn-out" -- overly stressed, insufficient rest and recovery -- and psychological breakdown.
4) Contradictions in pilots' medical evaluation for Fitness for Flying.
5) Design and protocol contradictions in cockpit security.
Airbus Instructional Video: Cockpit Door Security Procedure

The picture below shows James Reason famous, but dated model ("Swiss Cheese Model") for human error. Swiss cheese because, someday the holes in the Swiss cheese slices would line-up and the inevitable accident (that is "hidden" or "latent") will pass right through the holes and reveal itself. In a philosophical sense, accidents are not something accidental but are events lurking in the background (latent) and are just waiting to happen. Forgive me for the bleak portrayal of reality. In fact, Charles Perrow, for that very reason called all accidents as being NORMAL. He referred to them as "Normal Accidents." 

To summarize the above, accidents are not some abnormal events, but are embedded deeply in the very nature of high risk technologies. Probabilities could be low to very low, nevertheless, they are not Zero.

James Reason "Swiss Cheese Model" for Accident Causation

Introducing locked cockpit doors, or any solution, either introduces new risks and/or can be willfully defeated. They are revealed when the (hazards) holes get aligned and the adverse event slips through the holes.

And then we've the unforeseen or impossible to imagine Fat tail events: Low probability, high impact "Black Swan Events" (cf. Nassim Taleb). 

Wonder if the pilot locking himself in situation was ever foreseen before the accident in Risk Analysis -- when designing both the procedures and the cockpit security / door lock mechanisms. (No hindsight, please!)

Disasters with high hazard technology are here to stay -- where the size of dose (harm) or risk (probability of hazard to cause harm) can never be brought to zero. One shouldn't be surprised with accidents, as all accidents are "Normal Accidents"  (cf. Charles Perrow). This by the very nature of interventions -- a general Increase in complexity, due to added layers of components, layers, functions, interactivity (e.g., 2-pilots)  -- will not necessarily decrease the overall risk. A decrease in one plausible path for accident occurrence may end-up increasing in some other [foreseen or unforeseen] paths. 

The following may offer cold or no comfort: In an era, of aviation deregulation, budget airlines and airfares on a shoestring maybe light on our wallets but should weigh heavily on our minds. Lest we end-up paying a heavy price in life and limb that can't be measured by dollars.

Acknowledgements: Thanks to Vergil Den, Marc Resnick and Bapcha Man for enriching my analysis and thinking on the topic by sharing their insights on my social media page.

Moin Rahman
HVHF Sciences LLC

No comments:

Post a Comment