Definition
In the FAA risk assessment matrix, a severity level describing a hazard whose potential outcome is a major injury, major property damage, or a significant reduction in the ability to complete the flight safely, but stops short of catastrophic (loss of life or aircraft).
Plain English
A risk level meaning 'this could really hurt someone or break something important, but it probably wouldn't kill anyone or destroy the aircraft.' It is one step below the worst category.
Context Anchor
Seen in FAA risk assessment tools and PAVE checklist discussions when deciding whether a flight, lesson, or training activity is safe enough to continue.
Derivation
From Latin serius, meaning 'weighty' or 'grave.' In risk language, it keeps that weight: a Serious outcome is heavy enough to matter a great deal, even if it is not the worst possible.
Why Pilots Care
Correctly identifying a serious risk prompts required mitigation steps before flight, directly reducing the chance of injury or aircraft damage.
Intuition Check
Serious does not just mean “bad” or “scary” here. In this FAA risk-analysis context, it means the risk is high enough that the pilot must reduce it or change the plan before continuing.
Example Sentence 1
After weighing the gusty crosswind against his recent currency, the pilot rated the landing risk as Serious and chose a different airport with a runway aligned into the wind.
Example Sentence 2
Figure 10-2 rates the hazard serious when it could lead to injury requiring medical attention.