Definition
A mental or emotional condition that, under FAA medical certification standards, prevents a person from being legally eligible to hold a pilot medical certificate. Examples listed in FAR Part 67 include established psychosis, bipolar disorder, severe personality disorder manifested by overt acts, and substance dependence or abuse.
Plain English
A specific mental health condition that the FAA has decided makes a person ineligible to fly as a certificated pilot. If someone has one of these conditions, they cannot pass the medical exam required to fly.
Context Anchor
Seen in flight instructor guidance when a learner’s behavior raises a serious safety or medical-certification concern.
Derivation
‘Disqualifying’ comes from Latin roots meaning ‘to take away the qualification.’ In this context it means the condition removes the person’s eligibility to be certified. ‘Defect’ here is used in the medical-legal sense of a specific named condition, not as a general insult or judgment of character.
Why Pilots Care
Instructors must identify such conditions early to protect safety and avoid training someone who cannot legally or safely hold a certificate.
Intuition Check
This does not mean ordinary nervousness, stress, a bad attitude, or having a difficult lesson. In this FAA context, it means a serious mental or emotional condition that could affect whether the person is safe and eligible to fly.
Example Sentence 1
If a flight instructor observes behavior suggesting a disqualifying psychological defect, the appropriate step is to discontinue training and consult an Aviation Medical Examiner.
Example Sentence 2
FAA rules require that any disqualifying psychological defect be absent before a student can receive a medical certificate for solo flight.