Definition
In FAA usage, a defect, design flaw, or operating characteristic of an aircraft, engine, propeller, or appliance that the FAA has determined poses a risk to safe flight and that requires corrective action, typically through an Airworthiness Directive (AD).
Plain English
A problem found in an aircraft or one of its parts that the FAA has officially decided is dangerous enough that owners must fix it before continuing to fly.
Context Anchor
Seen in FAA safety discussions, required aircraft inspections, maintenance records, and notices that tell owners or operators to correct a known problem.
Why Pilots Care
When the FAA identifies an unsafe condition on a particular aircraft type, compliance with the resulting Airworthiness Directive becomes mandatory. A pilot or owner who ignores it is operating an unairworthy aircraft, which is both illegal and genuinely dangerous.
Intuition Check
Do not read unsafe condition as meaning the aircraft is certain to fail right now. In FAA use, it means a known problem or state exists that could affect safety and may require corrective action.
Example Sentence 1
After the manufacturer reported cracking in a certain engine mount, the FAA determined an unsafe condition existed and issued an Airworthiness Directive requiring inspection.
Example Sentence 2
An unsafe condition involving the fuel system prompted the FAA to issue an airworthiness directive affecting several models.