Changing Paradigms in Aviation Accidents

The causes of aviation accidents over the course of the last 70 years have changed significantly from design to human factors.† This presentation illustrates the importance to aviation attorneys of understanding both design-issues and human-interface (computer) issues presented in an accident investigation.† Several noteworthy accidents will be used to present real-world data.

1. Overview
   1. Comparison of commercial aviation statistics with other modes of transportation
   2. Overview accident causes
   3. Review safety issues facing manufacturers and regulators
      
2. Aviation Accident Timeline
   
3. Why the reduction?
   1. Preventative efforts
   2. Accident investigation leads to prevention
   3. New materials & technologies
   4. On-board devices
   5. ATC requirements
   6. Improved training
   7. Upgraded inspection techniques
      
4. Difficulty in reducing the rate of aircraft accidents
   1. Cause of modern commercial aircraft accidents has changed from straightforward engineering or training deficiencies to problems that are not so obvious or amenable to remediation
      
5. Engineering "Failures"
   1. Less than 10% of all commercial jet accidents
   2. Regulations and certification standards
   3. Small number of mechanical failures resulting in fatalities is a key to this
      
6. Engineering Dilemma
   1. DC-10 could fly safely with slats in different positions, as well as takeoff after the loss of one engine at a critical time
   2. Engine and pylon designed so that engine would separate from pylon before structural damage occurred
   3. Possibility of slat retraction after engine loss on takeoff not considered
      
7. Design Criteria
   1. How good should the design team be at foreseeing a failure cascade?
   2. How far should they design beyond regulations?
   3. What maintenance problems should be anticipated?
      
8. Human Factors
   1. Crew resource management has greatly reduced the human-error accident rate
   2. Errors not readily addressed by standard training methods
   3. "Psychology" of aircraft systems has not been addressed in the regulations
      
9. Challenges Ahead
   1. Coping with new technologies
      1. computers blur the distinction between pilot and aircraft
      2. failures causing the loss of an aircraft should be less than one in one billion flight hours
         
10. Additional Challenges
    1. Develop certification standards that strike the appropriate balance between public safety and economic feasibility
       1. challenges to develop certification for hardware and software are immense
       2. appropriate balance between safety and economics responding to accidents, particular with mechanical failures
          
11. The Future
    1. Safest method of transportation
    2. Cascading events are difficult to predict
    3. Man-made interface is extremely important
    4. Frequency of human error must reduce through audits and training
    5. Safety v. cost
       
12. Outcomes
    1. New design standards for structural safety of jet powered airframes and pressure cabins
    2. New certification requirements to assume a part is flawed and to show by analysis or test that the largest undetectable flaw will not grow to critical size before the next inspection