Darren Smith, Flight Instructor
  Home | Login | Schedule | Pilot Store | 7-Day IFR | IFR Adventure | Trip Reports | Blog | Fun | Reviews | Weather | Articles | Links | Helicopter | Download | Bio

Site Map


Private Pilot
  Learn to Fly

Instrument Pilot
  7 day IFR Rating
  IFR Adventure

Commercial Pilot

Multi-Engine Pilot

Human Factors/CRM

Recurrent Training

Ground Schools


Privacy Policy
About Me


Support this Website

The Heinrich/Smith Safety Triangle

by Darren Smith, CFII/MEI
Getting the Most From Your Flight Training, May, 2007
CFIDarren Newsletter, October 25, 2011
Navigation:  Bio | Schedule | About this website | Pilot Store | Pay for Services | News | Answerman | BeliefsPledge | Policy | Articles | Links | OnlineBFR/IPCGuestbook | Success Stories | Professionalism | FOTA | Threat & Error Management Series | CRM Series |

A recent helicopter accident once again reminded me how tenuous life is.  While the folks in this particular  incident survived, many times they don't. Just look at the monthly lists of accidents on the NTSB website and you'll see what I mean.  The problem in aviation is that it automatically cleanses itself of folks that don't belong.  How I wish that we can predict which folks would kill themselves in aviation.  Obviously we'd try to give them a hint.  The best we can do is offer the occasional web article we might stumble across. 

We've got to do better in preventing accidents & incidents.  It's taken 100 years but the first 99% of the effort has been completed.  That last 1% will probably take another 100 years.  For now we'll have to be satisfied with accident reports that state  pilot error as the cause.  I'm not quite satisfied with this conclusion that appears on some 90% of the reports in the NTSB database.

In doing some research on flight safety, I came across the work of H.W. Heinrich.  Mr. Heinrich was an Industrial Safety Engineer, who in 1931 developed a model describes how major injuries/industrial accidents occur. 

For a given population of workers, his model proposes that for every 300 unsafe acts there are 29 minor injuries and one major injury.  Heinrich's theory accounts for the first three levels of the model.  For more than 75 years, industrial safety managers have tried to reduce such accidents and injuries by attacking the problem from different ends of a three level pyramid.  They run around fixing frayed power cords, making sure equipment interlocks work, and enforcing safety rules.

How the Model Applies to Aviation

How we expand the model starts here.  In the expanded model, we focus on leading indicators.  These are the antecedents to the accident and is the only place we can focus to prevent them. The proposed model includes two additional layers called "Unsafe acts" and "Pilot Qualifications".

We all understand close calls.  We've all had them.  Some more than others.  And that's the point.  Some folks simply have more close calls, take more shortcuts & unnecessary risks.  Sometimes they are lucky.  Sometimes luck runs out.  If you keep playing darts, eventually you'll get a bull's-eye.  Out of 3,000 unsafe acts, one is going to be the winner that awards the pilot a check in the fatal column. 

Even more insidious is the "Pilot Qualifications" layer.  Imagine an employer reviewing all your flights, all the decisions you made on those flights, and all the little things that surprised you on all those flights.  Would the employer select you to be a pilot for them?   This layer includes (but not limited to):
  • Pilot qualifications
  • Decision making skills
  • Legally qualified & current?
  • Proficient & skilled?
  • Hazardous Attitudes?
  • Flying habits
  • Current Life Stress Events
  • Psychological make-up
  • Substance use?
  • Fatigue?
  • Medically qualified?  Healthy?
  • Mature thinking style?
  • Conservative?
  • Risk adverse?
  • Personal Lifestyle Choices (Credit-Criminal-Educational)

Where Do We Go From Here?

Attacking the triangle from the top is expensive, just look at what we spend in the NTSB budget for accident investigations.  The other problem with using the model starting at the top is that an accident is a lagging indicator which doesn't necessarily serve to prevent injuries.  To illustrate what I mean, take a look at the typical report and this nebulous term is used 90% of the time: "Pilot error."  Well how do you prevent that?  I guess it means an indepth analysis of all error and the root causes.  Got some spare time?  We've got a whole bunch of people looking at this data trying to come up with conclusions that define what action leads to what results.  It might be more complicated than we think. 

We're all convinced the answer is in the details.  Since pilot error is really human error, we need to focus on that Pilot Qualifications layer.  A sampling of news stories regarding airline pilot behavior tells us loudly that we need to focus on the  Pilot Qualifications layer.  Examine the items in that level of the model and you'll find the beginnings of the factors which lined up to create the perfect conditions in which the accident occurred.  The most obvious question is, "Do we still select you to work for X airlines?" Or, "Do we still select you  as a customer who can rent aircraft from us?"

In the June edition of Captain Anonymous, the Captain explores the current conditions for airline pilots and how things in the table above cause the events to the above right. 

Reader Comments

Date: Sun, 13 May 2007 06:50:29 Name = Brian H
Comments = In your article you say "The problem in aviation is that it automatically cleanses itself of folks that don't belong."  Yet often enough part 91 accidents include ATPs and commercial pilot with many hours.  An April 2007 accident involved an ATP with over 18,000 hours. It's just a little too cliche.
Reply:  Sure its cliche enough to be true.  Yes a few good ones slip through.  I think I am aware of the accident you are referring to.  In that case the pilot was not following the instrument procedure for the airport he was flying to.  If he were, would he have collided with terrain?  There were other factors that raise red flags for me personally:  experimental aircraft, real IFR conditions, business flight (time pressures?). We use the Personal Minimums Checklist to minimize risks of a given flight.  IFR is a game of rules and when we don't follow the rules precisely, its usually fatal.

Date: Thursday, 27 October, 2011 9:01 Name = Willie R
Comments = The CFI is the gatekeeper to the pilot qualification layer and there are precious few tools for a young (or seasoned) CFI to assess all of the requisites for a good pilot.  Maturity is the foundation upon which to build and the PTS does not give enough emphasis on ADM, CRM and the like. SAFE is addressing this as is NAFI but the road is long and the future unclear.

Your Thoughts...

Name: (Anonymous posts deleted)

E-mail: (if you want a reply)

How did you hear
of this website?
Message:  (What should I write?)
Business Card
News Group
Safety Seminar
Word of Mouth
(Required) Enter number from image to send:


Check this out...
   Home | Login | Schedule | Pilot Store | 7-Day IFR | IFR Adventure | Trip Reports | Blog | Fun | Reviews | Weather | Articles | Links | Helicopter | Download | Bio
All content is Copyright 2002-2010 by Darren Smith. All rights reserved. Subject to change without notice. This website is not a substitute for competent flight instruction. There are no representations or warranties of any kind made pertaining to this service/information and any warranty, express or implied, is excluded and disclaimed including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose. Under no circumstances or theories of liability, including without limitation the negligence of any party, contract, warranty or strict liability in tort, shall the website creator/author or any of its affiliated or related organizations be liable for any direct, indirect, incidental, special, consequential or punitive damages as a result of the use of, or the inability to use, any information provided through this service even if advised of the possibility of such damages. For more information about this website, including the privacy policy, see about this website.