Aircraft Safety: Man Versus Machine

Man-Machine Systems Engineering: how humans relate to technology and each other

High Expectations

Since the dawn of aviation, the prevailing expectation was that better technology would equal lower accident rates. However, in the late 1970’s we noticed that although Aviation technology had improved dramatically, accident rates remained stubbornly resistant to change. We found that improved technology was solving problems while creating others.

Cockpit Confusion

For example, more automation in the cockpit led to new ways of managing the aircraft, often with unintended consequences. Each pilot in a modern “glass” cockpit has an FMS (Flight Management System) computer screen. Simply put, on autopilot inputs into the FMS control the speed, altitude, and flight path of the aircraft. “If” one pilot should make inputs into the FMS without notifying the other pilot, each pilot could have a different idea of the future vector of the aircraft. This has happened on many occasions because one pilot assumed the other knew what he was doing. FMS technology has changed the rules on how we communicate in the cockpit, always notifying and obtaining acknowledgment from the other pilot when changes are made in the FMS.

Wiener’s Law

Dr. Earl Wiener addressed the idea that humans faced new challenges each time the technology changed with one of his famous Wiener’s Laws: “Any time you solve a problem you create one. The best you can hope for is that the one you solved is of greater magnitude than the one your created.”

The Human Factor

Innovative research by Drs. Bob Helmreich, Earl Wiener, John Lauber, and Clay Foushee, among many others, led the airline industry to focus on the one element that had not changed: the human element. Thus, a school of thought regarding how pilots relate to each other and to
the technology and tools they use was born. At the time, studies showed that 60-70% of all airline accidents were caused by human error, primarily by flight crews.

Top Training

To reduce this statistic, every major US airline began training pilots
in Human Factor skills. A series of programs, focused upon the human element, became known as CRM (Crew Resource Management). These programs expanded rapidly to include anyone who had a “dog in the fight” as flight attendants, mechanics, and flight controllers/dispatchers were incorporated into the expanded team.

The Power of Teamwork

Today, such courses and the skills they teach are part of commercial airline operations world-wide. CRM is not the only change that we’ve implemented in cockpit protocol over the past 25 years but it has been a huge part of the change. From early statistics showing 60-70% of all commercial aviation accidents were caused by human factor breakdowns, this figure is now in the 50% range. Might not seem like much, but this is a huge improvement. CRM cannot take credit for all of this improvement but is certainly a large part of it.

Risky Business

CRM concepts have also spread to military and corporate flight operations; more recently, CRM has moved beyond aviation to other high-risk, team-centered environments such as hospitals, chemical
plants, and nuclear control rooms. In some high-risk hospital settings, we’ve seen improvements of 50-75% in error/accident metrics.

Plane Comforts

CRM has made a difference. In aviation, there are many success
stories. Accident rates have been reduced. “There are old pilots and
bold pilots but no old bold pilots.” Safety is a systems-oriented
concept that can only be achieved through excellent teamwork. As you
begin your next flight, take comfort in knowing your crew has been
trained for the technical and human aspects of their jobs.

Fly Safely.

Captain Alan W. Price

Photos from Flickr. Photo credit: The cockpit of the Enola Gay by ten safe frogs

5 thoughts on “Aircraft Safety: Man Versus Machine”

  1. good to know that all that training is going towards flight safety — especially with the recent spate of crashes! It makes me feel a little better getting on a plane now.

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