Definition
A bias in assessment in which an instructor's overall positive impression of a student causes individual aspects of that student's performance to be rated more favorably than the actual performance warrants.
Plain English
When an instructor likes a student or thinks well of them in general, the instructor tends to rate every part of their flying better than it really was. The good overall impression spills over and colors each specific judgment.
Context Anchor
Seen in instructor training and flight evaluation discussions, especially when learning how to make fair, objective assessments.
Derivation
From 'halo,' the ring of light shown around the head of a saint in religious art, suggesting holiness or goodness. The term captures the idea that a single bright impression surrounds the person and makes everything about them look good, even parts that should be judged on their own merits.
Why Pilots Care
Halo error can allow a student to move forward with uncorrected weaknesses that later affect safety or checkride results.
Analogy
It is like liking a person's neat handwriting so much that you assume their math answer must also be correct. The nice handwriting is real, but it should not decide whether the math is right.
Intuition Check
Halo error does not mean the student made a flying error involving a visual halo or light effect. It means the evaluator's overall impression is affecting the judgment of specific performance.
Example Sentence 1
The chief instructor warned new CFIs to watch for halo error when grading their favorite students on checkrides.
Example Sentence 2
Because of halo error the student received a high grade even though radio communications remained weak.