The 5M model is a troubleshooting and risk-management model used for aviation safety.
[1][2] Based on T.P.
Wright's original work on the man-machine-environment triad[3] at Cornell University, the 5M model incorporates a diagram of 3 interlocking circles and one all-encompassing circle.
The smaller circles are labeled Man, Machine, and Medium; the intersecting space in the middle, where they all meet, is labeled Mission; while the larger circle is labeled Management: These have been expanded by some to include an additional three, and are referred to as the 8 Ms:[4] This is also used in more general troubleshooting or root-cause analysis, such as with the Ishikawa diagram.
[6]