Risk Matrix — Airline Safety Risk Register (ICAO Tolerability Matrix)
A hazard log for a fictional ATR 72 operator rated on the ICAO Doc 9859 tolerability matrix — cell by cell, not by L×I, with 4B-style risk indices: mitigations bring the two Intolerable hazards, an unstable approach (4B) and wing contamination (3A), down to Tolerable, leaving all eight hazards within the Tolerable appetite. Illustrative register.
Make it your own.
title "Regional airline SMS — hazard log, ATR 72 operation"
subtitle "Safety risk index and tolerability after ICAO Doc 9859 · probability 1–5, severity E (negligible) to A (catastrophic)"
likelihood-levels: 1=Extremely improbable, 2=Improbable, 3=Remote, 4=Occasional, 5=Frequent
impact-levels: E=Negligible, D=Minor, C=Major, B=Hazardous, A=Catastrophic
bands: Acceptable green, Tolerable amber, Intolerable red
# Rated cell by cell, as the ICAO matrix is — it is not a product of L and I.
matrix
5: T T I I I
4: T T T I I
3: A T T T I
2: A A T T T
1: A A A A T
appetite: Tolerable
note "Illustrative hazard log for a fictional airline; hazards, mitigations and indices are examples, not a safety assessment."
risk H1 "Unstable approach continued to landing on a short wet runway"
category: Runway excursion
owner: Head of Flight Operations
likelihood: Occasional
impact: Hazardous
control "Stabilised-approach gates at 1,000 ft with a no-fault go-around policy"
control "Flight data monitoring of every unstable approach"
residual: Remote x Hazardous
action "Fit runway-overrun awareness alerting to the fleet" due: 2027-Q4 owner: "Technical Director"
risk H2 "Take-off with frost or ice contamination on the wings"
category: Ground icing
owner: Ground Operations Manager
likelihood: Remote
impact: Catastrophic
control "De-icing programme with holdover-time tables"
control "Mandatory pre-take-off contamination check"
residual: Improbable x Catastrophic
risk H3 "Lithium battery fire in the passenger cabin"
category: Dangerous goods
owner: Cabin Safety Manager
likelihood: Remote
impact: Hazardous
control "Dangerous-goods acceptance checks at check-in"
control "Fire-containment bags and annual crew fire-fighting drills"
residual: Improbable x Major
risk H4 "Crew fatigue on consecutive early-start rosters"
category: Human factors
owner: Crew Planning Manager
likelihood: Occasional
impact: Major
control "Fatigue risk management system with bio-mathematical roster modelling"
control "No more than four early starts in a row"
residual: Remote x Major
action "Add a controlled-rest procedure to the operations manual" due: 2027-06 owner: "Chief Pilot"
risk H5 "Ground-equipment collision with a parked aircraft"
category: Ramp safety
owner: Ground Operations Manager
likelihood: Frequent
impact: Minor
control "Wing-walker policy for every push-back"
control "Speed limits and proximity sensors on ground vehicles"
residual: Remote x Minor
risk H6 "Level bust in a busy terminal area"
category: Airborne conflict
owner: Head of Flight Operations
likelihood: Remote
impact: Hazardous
control "Altitude call-out SOP and TCAS resolution-advisory training"
residual: Improbable x Hazardous
risk H7 "Bird strike on approach to the coastal base"
category: Wildlife
owner: Safety Manager
likelihood: Occasional
impact: Major
control "Airport wildlife hazard management plan"
control "ATC bird-activity alerts to crews"
residual: Remote x Major
risk H8 "Laser illumination of the flight deck on approach"
category: Security
owner: Security Manager
likelihood: Occasional
impact: Minor
control "Crew laser-strike procedure and immediate reporting to police"
residual: Occasional x Negligible