The bowtie templates were developed in consultation with Subject Matter Experts (SMEs) from
relevant sectors of the aviation industry in collaboration between the CAA and commercial
operators.
Extensive use was made of the workshop format with working groups of approximately six to eight
participants guided by experienced bowtie facilitators.
This process was used in order to capture accurate information relevant to the wide range of
industry sectors involved.
- An initial framework of hazard / top event combinations was developed outside of the workshop
environment based on the Significant Seven.
- In order to make efficient use of the workshops, the bowties were pre-populated with threats
and consequences that provided a starting point for the workshop discussions.
Core bowties
In total, three bowties for each of the Significant Seven were identified with a ‘core’ bowtie
selected and developed for each topic in order to address the highest risk scenarios.
These core bowties were fully developed over the course of two to three facilitated workshop
sessions. They include all of the basic bowtie components plus additional classifications and
ratings for the various diagram elements in order to maximise their potential. For example, the
expert judgement of the SMEs was an important component for decisions related to the control
effectiveness ratings.
The core bowties are complemented by additional supplementary bowties in order to address other
important aspects within the Significant Seven. These supplementary bowties were developed through
to the stage of identifying the basic controls to provide a starting point for further
refinement.