Building a Personal Risk Assessment Matrix
Every concept in this module — PAVE's hazard identification, DECIDE's structured response, resistance to external pressure — leads to the same practical question: once a hazard is identified, how risky is it, really, and is that risk acceptable? A risk assessment matrix answers that question with numbers instead of a gut feeling. This lesson builds a standard 5×5 risk matrix from the ground up, scoring severity against likelihood, and includes a working calculator so you can score a real hazard the same way a working remote pilot would before a mission.
Why a numeric matrix beats a gut feeling
Every prior lesson in this module has built toward identifying hazards (PAVE) and structuring a response to them (DECIDE), but neither tells you how to weigh one hazard against another, or when a hazard is serious enough to cancel a flight versus one that's acceptable with a small mitigation. A risk assessment matrix solves this by scoring two independent factors — how bad the outcome would be if the hazard materializes, and how likely it actually is to happen — and combining them into a single, comparable number. This turns a vague impression ("that seems kind of risky") into a specific, repeatable score that doesn't shift based on how tired or rushed the pilot happens to feel that day.
Severity: how bad would the outcome be?
Severity measures the worst reasonably foreseeable outcome if the hazard actually occurs, rated on a five-point scale from Negligible (essentially no consequence) to Catastrophic (loss of the aircraft, serious injury, or worse). Severity should be assessed independently of how likely the event is — a rare but catastrophic possibility (losing control near a crowd) is scored on how bad it would be if it happened, not discounted just because it's unlikely.
Likelihood: how probable is it?
Likelihood measures how probable the hazard actually occurring is, on a five-point scale from Rare (would only happen in exceptional circumstances) to Almost Certain (expected to occur in most similar situations). Likelihood is assessed based on the pilot's honest read of current conditions and history — a wind gust exceeding rated limits is far more likely in a forecast already showing gusts near that limit than in one showing calm, stable conditions.
Combining severity and likelihood into a risk score
Multiplying severity by likelihood produces a single risk score from 1 (lowest) to 25 (highest), which maps onto a color-coded risk category: Low, Medium, Serious, or High. A hazard that's catastrophic but extremely rare and a hazard that's minor but almost certain can land in a similar risk band, even though they feel very different — which is exactly the point of using a matrix instead of intuition alone: it forces both factors to be weighed together rather than one dominating the decision just because it feels more vivid.
A standard 5×5 risk assessment matrix: each cell's color and score come from multiplying its severity and likelihood ratings.
View LargerRisk Score Calculator
Worked example: scoring a wind hazard
You're planning a rooftop inspection with a forecast showing gusts occasionally reaching your aircraft's rated wind limit. If a gust exceeds the limit during flight, the realistic worst case is a loss of control near the structure — a Major severity (4), since it could cause real property damage or injury but stops short of a worst-case catastrophic scenario given the aircraft's size and the structure's setting. Given the forecast already shows gusts approaching the limit, this is Likely (4). Risk Score = 4 × 4 = 16, landing in the High (red) category — this flight should not proceed as planned; either the mission needs to wait for a better weather window, or a specific, effective mitigation (a hard personal cutoff well below the rated limit, monitored live) needs to bring the effective likelihood down before reconsidering.
Worked example: scoring a minor equipment concern
During preflight you notice slight, cosmetic scuffing on a propeller with no crack or structural damage. The realistic worst case if this scuffing somehow affects performance is a minor efficiency loss — Minor severity (2). Given the scuffing is purely cosmetic and the propeller passed a close inspection, an actual performance issue is Unlikely (2). Risk Score = 2 × 2 = 4, landing in the Low (green) category — acceptable to proceed with standard precautions, noting the propeller for replacement at the next convenient maintenance interval.
The matrix identifies risk; it doesn't replace judgment
A risk matrix is a decision-support tool, not a decision-making machine. A Medium score doesn't automatically mean "proceed" — it means the pilot should identify a specific mitigation that genuinely reduces either severity or likelihood before proceeding, and should be able to state what that mitigation actually is. A pilot who scores a hazard as Medium and proceeds without any real mitigation has used the matrix as a rubber stamp rather than as the risk-management tool it's meant to be.
Building this into a personal, reusable practice
The real value of a risk matrix comes from using it consistently, not from perfect precision on any single score. A pilot who runs every identified PAVE hazard through the same matrix, using the same severity and likelihood definitions each time, builds a calibrated, repeatable sense of what "moderate" and "likely" actually mean for their specific operations — far more reliable over time than re-deciding each hazard's seriousness from scratch, under whatever pressure happens to be present that day.
| Risk score range | Category | Recommended action |
|---|---|---|
| 1–4 | Low (green) | Acceptable; proceed with standard precautions |
| 5–9 | Medium (yellow) | Proceed only with a specific, stated mitigation in place |
| 10–14 | Serious (orange) | Do not proceed without an effective mitigation that meaningfully lowers the score, or a second opinion |
| 15–25 | High (red) | Do not fly; redesign, reschedule, or decline the mission |
Scoring a Hazard You've Identified
Use this sequence for any hazard flagged during a PAVE scan or noticed at any other point before a flight.
State the hazard specifically
Write down exactly what the hazard is, not a vague category — "gusts near the aircraft's rated wind limit," not just "windy."
Score severity honestly, independent of likelihood
Ask "if this hazard actually occurs, what's the realistic worst outcome?" without letting how unlikely it feels lower the severity score.
Score likelihood based on actual current conditions
Base this on the specific forecast, aircraft condition, or site situation in front of you today, not a generic assumption.
Multiply and check the risk category
Use the calculator above or the reference table to find the resulting category and recommended action.
If mitigation is needed, state it specifically before proceeding
A vague intention to "be careful" is not a mitigation. State exactly what will reduce severity or likelihood, and confirm it's actually in place before launch.
| Mistake | Why it happens | Correct understanding | Regulation / source |
|---|---|---|---|
| Lowering the severity score because the hazard feels unlikely | Severity and likelihood get mentally blended together | Severity should be scored independently, based only on how bad the outcome would be if it occurred. | FAA Risk Management Handbook |
| Treating a Medium score as automatic permission to proceed | Medium sounds like "acceptable" by default | A Medium score requires a specific, stated mitigation before proceeding, not an automatic go. | FAA Risk Management Handbook |
| Believing the risk matrix is an FAA-mandated numeric standard | The precision of a numeric score feels official or regulatory | This is a widely used risk-management tool, not a specific numbered Part 107 requirement; ACS Task V.D tests the underlying judgment it represents. | ACS Task V.D |
| Treating "be more careful" as a valid mitigation | It feels like a responsible-sounding response to a flagged risk | A genuine mitigation must specifically and measurably reduce severity or likelihood, not just express good intentions. | FAA Risk Management Handbook |
Is the specific numeric matrix in this lesson an official FAA standard?
No. There is no single, official numbered Part 107 risk matrix. The 5×5 severity-times-likelihood approach taught here is a widely used risk-management pattern that supports the underlying judgment tested under ACS Task V.D, and many operators build their own version calibrated to their specific aircraft and mission types.
What should I do if I'm unsure whether to round a rating up or down?
When genuinely uncertain between two adjacent severity or likelihood ratings, choosing the higher (more conservative) rating is the safer error, since it results in a more cautious recommended action rather than a less cautious one.
Can two very different hazards land in the same risk category?
Yes, and that's intentional. A catastrophic-but-rare hazard and a minor-but-almost-certain hazard can produce similar risk scores, which is the point of multiplying the two factors together rather than judging on severity or likelihood alone.
Do I need to run every single hazard through the full calculator during a real preflight?
Not necessarily with the calculator itself every time — with practice, a pilot internalizes the severity and likelihood scale well enough to estimate a score mentally in seconds. The calculator and written matrix are most valuable when learning the skill or when scoring a genuinely ambiguous, high-stakes hazard.
Test Your Knowledge
Answer the questions below to check your understanding. Every answer can be found in the lesson above.