Safety Performance Indicators: Measuring What Matters in Aviation Safety

Safety Assurance monitors whether safety controls work as intended.

Safety Performance Indicators (SPIs) show how well they work.

SPIs turn complex operational data into measurable insight. They make safety performance visible, and that visibility is what allows organizations to make informed, timely decisions.

Safety Performance Indicators — the pulse check of your safety system.

What Are Safety Performance Indicators?

Safety Performance Indicators are measurable metrics used to monitor and evaluate safety performance over time. They help answer questions like:

• “Are we meeting our safety objectives?”

• “Are our risk controls effective?”

• “Where is performance starting to drift?”

SPIs transform raw data into early warning signals. When chosen well, they show not just what is happening, but why, allowing the Safety Department to act before an event occurs.

Why Safety Performance Indicators Matter?

Every organization collects data, but data alone doesn’t drive safety improvement. It’s what you do with it that counts.

SPIs bring focus to the right information. They allow management to:

• Track whether risk controls remain effective.

• Detect trends before they become hazards.

• Prioritize safety actions and allocate resources.

• Demonstrate performance to regulators and partners.

In short, SPIs are the pulse check of your safety system, they keep Safety Assurance grounded in measurable reality.

Different Types of SPIs

Not all indicators serve the same purpose. A healthy SPI portfolio includes a balance of outcome, process, and output indicators:

🔹 Safety Outcome Indicators: These measure end results, for example, number of unstable approaches per 100 sectors or maintenance-related delays per 500 flight hours. They reflect the “what happened” side of safety performance and help operators spot meaningful trends without waiting for large data volumes to accumulate.

🔹 Process Indicators: These show how well safety activities are being carried out, for example, percentage of closed findings within 30 days or timeliness of risk assessments. They track how effectively the safety system operates.

🔹 Output Indicators: These measure the products of safety activities, for instance, number of safety briefings delivered or training sessions completed. While not direct measures of risk, they reveal the strength of safety promotion and engagement.

Each type complements the others. Together, they show both the results and the effort behind maintaining safety.

Making SPIs Meaningful

An SPI only adds value if it is:

• Relevant – directly linked to an identified risk or safety objective.

• Measurable – supported by reliable data sources.

• Understandable – clearly defined so everyone interprets it the same way.

• Actionable – able to trigger corrective action or review when thresholds are crossed.

Too many organizations collect dozens of indicators but use only a few. The goal isn’t quantity, it’s clarity. A few well-chosen SPIs monitored consistently tell a stronger story than a spreadsheet full of numbers.

In my experience, the Accountable Manager often becomes fully engaged only when information is presented in statistical format. When trends are visualized instead of just described. A simple chart or graph showing movement over time can make the difference between a discussion and a decision.

That’s the real value of SPIs: they translate safety information into a language management can act on.

Reviewing and Communicating Results

SPIs are most powerful when reviewed regularly — monthly, quarterly, or seasonally — depending on the organization’s flight activity. If you operate a small fleet with limited monthly flying, quarterly reviews may give a more meaningful trend. For larger operations or those with frequent daily flights, monthly reviews provide the right rhythm to detect small changes early.

The important part isn’t the calendar, it’s consistency. Reviewing data at a frequency that matches your operation ensures that trends are visible and that decisions are based on evidence, not assumptions.

When flight crews, maintenance engineers, and ground staff understand what is being monitored and why, they can contribute to improving the numbers, not just reporting them.

Safety assurance is not complete until the insight from SPIs is communicated back to the people who make change happen. That’s what turns measurement into learning, and learning into improvement.

Looking Ahead

In the next article, we’ll put SPIs into practice with examples of how to calculate and interpret safety indicators that matter.