Prevention of carbon monoxide exposure in general and recreational aviation

Carbon monoxide exposure is an important public health issue that poses a significant, albeit uncommon risk in aviation. Exposure is most common in single engine piston-driven aircraft where air is passed over the exhaust manifold to serve as cabin heat. Effective primary prevention of this exposure is the regular inspection and maintenance of aircraft exhaust systems, as required by law. For situations at special risk should exposure occur, and where there is concern for the public safety, installation of active warning devices for CO intrusion into cockpits may improve secondary prevention. Modern studies should be performed of occupation-specific abilities to support the 50 ppm FAA CO exposure standard and 50-70 ppm FAA Technical Standard Order (TSO) for CO monitors alerting pilots to the possibility of exhaust gas intrusion into their cockpits.

Development and application of a human error identification tool for air traffic control

This paper outlines a human error identification (HEI) technique called TRACEr--technique for the retrospective and predictive analysis of cognitive errors in air traffic control (ATC). The paper firstly considers the need for an HEI tool in ATC, and key requirements for the technique are noted. The technique, which comprises a number of inter-related taxonomies, based around a simple cognitive framework, is then described. A study concerning a real-world application of TRACEr is outlined-the evaluation of several options for reduced separation minima in unregulated UK airspace. In this study, TRACEr was used predictively and retrospectively, looking forward to pre-empt potential problems and looking back to learn from experience. The paper concludes that TRACEr is a valuable aid to design, development and operations in UK ATC, and has indeed been used as a basis for further applications in ATC both in Europe and the USA.

Teaming humans and automated systems in safely engineered environments

Human factors research has historically been concerned with interactions among humans, machines, and the environments in which they operate. The introduction of intelligent, automated systems to support human performance and safety in a variety of challenging environments, including undersea systems, high-performance aircraft, and orbiting space stations, has introduced a new dynamic to these relationships. Many missions cannot be accomplished without the active participation of both intelligent human and intelligent machine members. This is particularly true in environments where individuals operate in isolation and without easy access to support crews. However, the teaming of these two systems that function in such different ways can lead to new types of error, with the human frequently unable to determine what the machine is doing and why. The challenge, then is to develop automated systems that support, rather than confound, the human user. Aerospace human factors research has been a leader in attempting to understand human-automation interactions and in establishing guidelines for the design and use of automated systems. This article discusses some of the human-automation interaction problems that have been observed operationally, what the existing research reveals, and several approaches that are being pursued to avoid "disconnects" between humans and automation. Once these disconnects are overcome, intelligent humans and intelligent machines will be able to work together more productively, thus leading to our furthered presence in a variety of challenging environments.

Intelligibility of speech in a virtual 3-D environment

In a simulated air traffic control task, improvement in the detection of auditory warnings when using virtual 3-D audio depended on the spatial configuration of the sounds. Performance improved substantially when two of four sources were placed to the left and the remaining two were placed to the right of the participant. Surprisingly, little or no benefits were observed for configurations involving the elevation or transverse (front/back) dimensions of virtual space, suggesting that position on the interaural (left/right) axis is the crucial factor to consider in auditory display design. The relative importance of interaural spacing effects was corroborated in a second, free-field (real space) experiment. Two additional experiments showed that (a) positioning signals to the side of the listener is superior to placing them in front even when two sounds are presented in the same location, and (b) the optimal distance on the interaural axis varies with the amplitude of the sounds. These results are well predicted by the behavior of an ideal observer under the different display conditions. This suggests that guidelines for auditory display design that allow for effective perception of speech information can be developed from an analysis of the physical sound patterns.

DWI convictions linked to a higher risk of alcohol-related aircraft accidents

This paper assesses whether persons convicted of driving while intoxicated (DWI) are at increased risk of alcohol-related general aviation accidents. Past research has shown a clear link between DWI convictions and pilot-error accidents in commercial aviation. However, no study in the literature has addressed whether DWI convictions are associated with an increased risk of alcohol-related aircraft accidents. To evaluate a hypothesis, a total of 308912 pilot records over a 10-year period were analyzed using logistic regression. After potentially confounding variables were controlled, DWI convictions were found to be associated with alcohol-related aviation accidents. Pilots with DWI convictions were about 3.5 times more likely than pilots without convictions to have alcohol-related general aviation accidents. Actual or potential applications of this research include providing policy makers with data-driven information that is useful in improving decisions related to the medical certification of pilots.

American Academy of Pediatrics. Restraint use on aircraft. Committee on Injury and Poison Prevention

Occupant protection policies for children younger than 2 years on aircraft are inconsistent with all other national policies on safe transportation. Children younger than 2 years are not required to be restrained or secured on aircraft during takeoff, landing, and conditions of turbulence. They are permitted to be held on the lap of an adult. Preventable injuries and deaths have occurred in children younger than 2 years who were unrestrained in aircraft during survivable crashes and conditions of turbulence. The American Academy of Pediatrics recommends a mandatory federal requirement for restraint use for children on aircraft. The Academy further recommends that parents ensure that a seat is available for all children during aircraft transport and follow current recommendations for restraint use for all children. Physicians play a significant role in counseling families, advocating for public policy mandates, and encouraging technologic research that will improve protection of children in aircraft.

Human error analysis of commercial aviation accidents: application of the Human Factors Analysis and Classification system (HFACS)

BACKGROUND

The Human Factors Analysis and Classification System (HFACS) is a general human error framework originally developed and tested within the U.S. military as a tool for investigating and analyzing the human causes of aviation accidents. Based on Reason's (1990) model of latent and active failures, HFACS addresses human error at all levels of the system, including the condition of aircrew and organizational factors. The purpose of the present study was to assess the utility of the HFACS framework as an error analysis and classification tool outside the military.

METHODS

The HFACS framework was used to analyze human error data associated with aircrew-related commercial aviation accidents that occurred between January 1990 and December 1996 using database records maintained by the NTSB and the FAA.

RESULTS

Investigators were able to reliably accommodate all the human causal factors associated with the commercial aviation accidents examined in this study using the HFACS system. In addition, the classification of data using HFACS highlighted several critical safety issues in need of intervention research.

CONCLUSION

These results demonstrate that the HFACS framework can be a viable tool for use within the civil aviation arena. However, additional research is needed to examine its applicability to areas outside the flight deck, such as aircraft maintenance and air traffic control domains.

Cockpit-cabin communication: II. Shall we tell the pilots?

In a previous article (Chute & Wiener, 1995), we explored the coordination between the "two cultures" in an airliner's crew: cockpit and cabin. In this article, we discuss a particular problem: the dilemma facing the cabin crew when they feel that they have safety-critical information and must decide whether to take it to the cockpit. We explore the reasons for the reluctance of the flight attendant to come forward with the information, such as self-doubt about the accuracy or importance of the information, fear of dismissal or rebuke by the pilots, and misunderstanding of the sterile cockpit rule. Insight into crew attitudes was based on our examination of accident and incident reports and data from questionnaires submitted by pilots and flight attendants at two airlines. The results show confusion and disagreement about what is permissible to take to the cockpit when it is sterile, as well as imbalances in authority and operational knowledge. Possible remedies are proposed.

Automation bias: decision making and performance in high-tech cockpits

Automated aids and decision support tools are rapidly becoming indispensable tools in high-technology cockpits and are assuming increasing control of"cognitive" flight tasks, such as calculating fuel-efficient routes, navigating, or detecting and diagnosing system malfunctions and abnormalities. This study was designed to investigate automation bias, a recently documented factor in the use of automated aids and decision support systems. The term refers to omission and commission errors resulting from the use of automated cues as a heuristic replacement for vigilant information seeking and processing. Glass-cockpit pilots flew flight scenarios involving automation events or opportunities for automation-related omission and commission errors. Although experimentally manipulated accountability demands did not significantly impact performance, post hoc analyses revealed that those pilots who reported an internalized perception of "accountability" for their performance and strategies of interaction with the automation were significantly more likely to double-check automated functioning against other cues and less likely to commit errors than those who did not share this perception. Pilots were also lilkely to erroneously "remember" the presence of expected cues when describing their decision-making processes.

Enhancing transfer of training: using role-play to foster teamwork in the cockpit

Role-plays serve a unique purpose in providing practice and feedback for aircrew team development training in the classroom. When compared with other training strategies, role-play provides targeted practice and feedback of specific behaviors at low cost, with the trade-off being the amount of fidelity it provides. This article presents guidelines for designing role-plays to elicit crew resource management (CRM) behaviors and providing feedback to trainees on their performance. Through careful design procedures, a role-play exercise can provide both targeted practice and feedback and serve a useful purpose in the overall training design of a CRM training program.

Cockpit-cabin communication: I. A tale of two cultures

Several dramatic accidents have emphasized certain deficiencies in cockpit-cabin coordination and communication. There are historical, organizational, environmental, psychosocial, and regulatory factors that have led to misunderstandings, problematic attitudes, and suboptimal interactions between the cockpit and cabin crews. Our research indicates the basic problem is that these two crews represent two distinct and separate cultures and that this separation serves to inhibit satisfactory teamwork. A survey was conducted at two airlines to measure attitudes of cockpit and cabin crews concerning the effectiveness of their communications. This article includes recommendations for the improvement of communications across the two cultures.

Anatomy of a system accident: the crash of Avianca Flight 052

On January 25, 1990, Avianca Flight 052 crashed after running out of fuel following a missed approach to New York's John F. Kennedy Airport. Weather was poor on the East Coast of the United States that day, and the flight had experienced several holding patterns enroute from Medellín, Colombia, to New York. The accident is analyzed in terms of Helmreich and Foushee's (1993) model of crew performance and Reason's (1990) model of latent pathogens in system operations.

The evolution of Crew Resource Management training in commercial aviation

In this study, we describe changes in the nature of Crew Resource Management (CRM) training in commercial aviation, including its shift from cockpit to crew resource management. Validation of the impact of CRM is discussed. Limitations of CRM, including lack of cross-cultural generality are considered. An overarching framework that stresses error management to increase acceptance of CRM concepts is presented. The error management approach defines behavioral strategies taught in CRM as error countermeasures that are employed to avoid error, to trap errors committed, and to mitigate the consequences of error.

Three-dimensional audio versus head-down traffic alert and collision avoidance system displays

The advantage of a head-up auditory display for situational awareness was evaluated in an experiment designed to measure and compare the acquisition time for capturing visual targets under two conditions: standard head-down Traffic Alert and Collision Avoidance System display and three-dimensional (3-D) audio Traffic Alert and Collision Avoidance System presentation. (The technology used for 3-D audio presentation allows a stereo headphone user to potentially localize a sound at any externalized position in 3-D auditory space). Ten commercial airline crews were tested under full-mission simulation conditions at the NASA-Ames Crew-Vehicle Systems Research Facility Advanced Concepts Flight Simulator. Scenario software generated targets corresponding to aircraft that activated a 3-D aural advisory (the head-up auditory condition) or a standard, visual-audio TCAS advisory (map display with monaural audio alert). Results showed a significant difference in target acquisition time between the two conditions, favoring the 3-D audio Traffic Alert and Collision Avoidance System condition by 500 ms.

[Unruly passengers - resistance to requests by flight attendants]

Travelling by airplane is of increasing importance in modern society. Psychiatric disorders seldom cause incidents in aircrafts. Scandal sheets and serious newspapers as well report on disturbances of a flight by psychiatric patients. Up until now psychiatric research is not engaging in unruly flight passengers suffering from psychotic symptoms. We describe a passenger who became psychotic during an international flight. In addition, we provide an overview over publications dealing with unruly passengers due to psychosis and describe similar cases.

Cultural variation of perceptions of crew behaviour in multi-pilot aircraft

As the "last line of defence" pilots in commercial aviation often have to counteract effects of unexpected system flaws that could endanger the safety of a given flight. In order to timely detect and mitigate consequences of latent or active failures, effective team behaviour of the crew members is an indispensable condition. While this fact is generally agreed in the aviation community, there seems to be a wide range of concepts how crews should interact most effectively. Within the framework of the European project JARTEL the cultural robustness of evaluations of crew behaviour was examined. 105 instructor pilots from 14 different airlines representing 12 European countries participated in this project. The instructors' evaluations of crew behaviours in eight video scenarios will be compared in relation to cultural differences on Hofstede's dimensions of Power Distance and Individualism.