Not an Engineer's fault

Aviation, today is much safer than we ever thought .

What made this seemingly riskiest transport the safest ?

As an Engineer in IAF, I was a close witness to many air accidents and crashes. Some of these crashes took life of some of my close friends. What you often read in newspapers after accidents is a ceremonial – “A Court of inquiry(CoI) has been ordered by Air Head Quarters..“  Typically, these CoIs last for weeks, if not months and more often, than not, the findings put the accident/incident under 2 broad buckets

1.    Technical/ Material failure : One of the components or structure failed

2.    Human Error(HE) : Either, the pilot or some ground guy( ATC or Fighter controller) instructing the pilot made an error

While for the former, the root cause analysts investigate engineering aspects, in the later case often inquiry is done into behavioral aspects. I do not have hard data on the distribution of blame but by my general observation is that if its possible to apportion blame on technical/material failure, its easily resorted to. The materials have less reputation to protect and do not have voice.

Now coming to HE, if we analyze it objectively, it points us to the one of these following:

1.    Lack of skill/competency // Almost impossible. Pilots go through the most rigorous selection process and training. There are no reserved seats here.

2.    Negligence or indiscipline // Rarest of rare, pilots are one of the most disciplined lot. Their life depends on it.

3.    Honest mistakes // Attributable to natural reaction of any human being under those circumstances. This often points to design errors

It’s the 3rd one which requires large systemic changes to eliminate aviation accidents. It led to birth of a new discipline of study and that is called Human Factors Engineering or HFE

A Human factor engineer observing the air accidents observed that pilots were inadvertently activating a control that raised the landing gear during landing, confusing it with a control that operated the flaps (to slow down the aircraft).

This was because these two controls were similarly shaped and placed next to each other. He suggested a new design: A landing gear control that looked and felt like a landing gear (It persists today in modern aircraft). It had wheel shape on the grip.

 He also redesigned the flap control in a shape of triangle which mimicked the shape of flaps. This ensured that when pilots, with their gaze on approaching runway, gripped the lever without even looking at them, they instantly identified the lever gripped by sense of touch of wheel or triangle.

Human factors and usability professionals have been intimately involved in the design and operation of aircraft ever since. This involvement has helped push the overall rate of aircraft fatalities (as measured by fatalities per million passenger boardings) down 96% since 1970 (Savage, 2013), making air travel the safest form of transportation.

The human factors engineer who brought about this change was Alphonse Chapanis. He is widely considered to be the father of human factors. He demonstrated that the designs of systems could cause people to use them incorrectly. He set in motion a profession that would dramatically change the aviation industry.

After thoughts :  There was nothing wrong with the engineers who were focused on making the landing gear and flap control work perfectly. They wanted them to be in close reach of the pilot and near to each other as pilots use them nearly at the same time during landing. It took a cognitive scientist to observe that it was design flaw, not the fault of pilots and that observation changed aviation forever. Today there are millions of engineers who are creating 1000s of machine interfaces, totally oblivious of blunders, their software can make humans to do. It only takes a human factors or a Ux engineer to figure out the benign placement from malignant.