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LOSA development was initially started in 1991 at the University of Texas at Austin (UT-Austin) with funding from the FAA. The development of LOSA stemmed from a request by Delta Air Lines to validate the operational impact of its three-day Crew Resource Management (CRM) training course. Analysts soon realized that existing data collection methods did not assemble adequate information regarding flight crew adherence to Standard Operating Procedures (SOPs) and environmental influences on flight crew performance.

Initial Development

To explore the effectiveness of training transfer, a partnership was established between the UT-Austin Human Factors Research Project and Delta Air Lines in 1994. The goal was to develop a line audit methodology utilizing jump-seat observations on regularly scheduled flights (i.e., LOSA). In its early form, LOSA mostly focused on CRM performance (Klinect, Murray, Merritt, & Helmreich, 2003). The audits provided actionable data about strengths and weaknesses allowing prioritization and improvement of training. They also supported the validity of findings from the training data. Other major airlines then conducted their own CRM audits in collaboration with UT-Austin over the next couple of years.

A Shift to the Threat and Error Management Framework

The next major development of LOSA evolved from the advancement of systems thinking and human error research in the field of aviation human factors. In 1997, the UT-Austin team collaborated with Continental Airlines to expand the method to focus on the management of regular threats and errors. This ultimately evolved into the Threat and Error Management (TEM) model and the creation of the current LOSA's underlying theoretical framework. In 1997 and 1998, the UT-Austin research team conducted LOSA at three airlines (Klinect, Wilhelm, & Helmreich, 1999). The observers documented threats (external events such as adverse weather or errors originated by non-cockpit personnel), recorded flight crew error, and rated the crew using CRM behavioral markers in accordance with TEM performance. Along with the documented threats and errors, observers also recorded how each event was managed by the flight crew. Initial data showed that threats and errors are common and varied across airlines. Notably, LOSA data illuminated the behaviors that led to effective and ineffective threat and error management.

The nuances included in this proactive data collection strategy populate a richer and more extensive library of threats and errors than reactive accident/incident reporting. LOSA examines responses to errors that have not reached an accident or incident. Capturing effective responses, allows LOSA data to provide insight into normal flight operations and aid training. Follow-up studies showed a sizable improvement at Continental Airlines related to safety and overall crew performance (Klinect et al., 2003).

LOSA in the 21st Century

LOSA was first operationally deployed as an International Civil Aviation Organization (ICAO) endorsed safety program following the First LOSA Week, which was hosted by Cathay Pacific Airways in March, 2001. After several years of development and refinement, LOSA has evolved into a strategy to provide safety data comprised of normal operations in technical and human performance areas. The LOSA observations provide data to develop countermeasures to operational threats and errors (ICAO, 2002). It has since been used and validated by many international airlines and is now recognized as a key element in an airline's SMS. It also provides a data-driven mechanism for measuring change (Veilette, 2008). Based on the success at many LOSA carriers, the International Civil Aviation Organization (ICAO) made LOSA a central focus of its Flight Safety and Human Factors Program and endorsed it as an industry best practice for normal operations monitoring. The FAA also endorses LOSA as one of its voluntary safetyprograms (Merritt & Klinect, 2006).

UT-Austin provided "how-to" guides as an open source through numerous conference presentations and papers to the airline industry about flight deck LOSA, as well as details why and how to set up a LOSA. UT-Austin helped develop two primary guidelines: 1) Line Operations Safety Audit (LOSA) (ICAO, 2002), and 2) Advisory Circular 120-90 Line Operations Safety Audits (FAA, 2006).Consequently, The LOSA Collaborative (a private organization) was formed in the interest of protecting the collected LOSA data.