discrepancy

Definition

A noted difference between the actual condition or performance of an aircraft, system, or component and the condition or performance required by approved specifications, manuals, or standards. In maintenance practice, a discrepancy is recorded so it can be investigated, deferred, or corrected before the aircraft is returned to service.

Plain English

Something that isn't the way it's supposed to be. A pilot or mechanic spots that a part, system, or instrument isn't behaving correctly, writes it down, and it stays on the record until someone fixes it or formally clears it.

Context Anchor

Pilots most often see this word in preflight inspections, aircraft logbooks, maintenance write-ups, and checklist procedures.

Derivation

From Latin discrepare, meaning 'to sound differently' or 'to disagree.' The original sense was of two things not matching — like two voices out of tune. In aviation, that idea carries directly: the actual condition disagrees with the required condition.

Why Pilots Care

Unresolved discrepancies in fuel, instruments, or airworthiness records can affect safety and regulatory compliance.

Intuition Check

Do not read discrepancy as just a small paperwork difference. In aviation, a discrepancy can be anything from a minor record issue to a real aircraft problem that must be fixed or approved before flight.

Example Sentence 1

After landing, the pilot wrote up a discrepancy noting that the landing light failed to illuminate during the approach.

Example Sentence 2

Maintenance noted a discrepancy in the engine tachometer logs from the previous two flights.

Definition

A difference, mismatch, or inconsistency between two things that should agree — for example, between an observed condition and a published standard, between a student's performance and the established standard, or between an aircraft's actual condition and its required airworthy state.

Plain English

Something that doesn't match what it should match. The two things were supposed to line up, and they don't.

Context Anchor

Pilots may see this word in training notes, aircraft records, checklists, preflight findings, or instructor comments about a student’s performance.

Derivation

From Latin discrepantia, meaning 'a sounding apart' or 'disagreement.' The image is of two notes that should be in tune but aren't. That captures the aviation use well: two things that should agree, but don't.

Why Pilots Care

In training, identifying a discrepancy is the first step toward correcting it. In maintenance, an unresolved discrepancy can mean the aircraft is not airworthy. Either way, the word signals something that needs attention before moving on.

Intuition Check