At its core, the FAA’s medical certification system exists for one reason: aviation safety. Any medical condition that increases the risk of sudden or insidious incapacitation is a concern. Substance abuse and substance dependence fall squarely into that category.
The FAA is not focused on morality, social norms, or whether someone “seems fine.” The concern is operational risk. Alcohol and other psychoactive substances impair cognition, judgment, reaction time, situational awareness, and executive function. More importantly for aviation, these effects are not always obvious to the individual experiencing them. Tolerance, denial, and impaired insight are hallmark features of substance-related disorders.
Risk of Incapacitation
There are two major incapacitation risks the FAA worries about:
- Sudden incapacitation – acute intoxication, withdrawal, hangover effects, or relapse.
- Insidious incapacitation – chronic cognitive impairment, poor decision-making, increased risk-taking, and erosion of safety margins over time.
Studies have shown that individuals with alcohol use disorder demonstrate persistent deficits in attention, executive function [1], and psychomotor speed [2] even during periods of abstinence. Meanwhile, relapse rates are significant, particularly without structured treatment and monitoring [3].
From a safety standpoint, aviation cannot tolerate unpredictable lapses in judgment or performance—especially in single-pilot or high workload environments.
What the Law Actually Says: The CFR
The FAA’s authority comes from federal law, not from clinical opinion or evolving psychiatric standards. The relevant regulations are found in 14 CFR Part 67, which governs medical certification standards.
For example, 14 CFR §67.107 (First Class), §67.207 (Second Class), and §67.307 (Third Class) all contain similar language. The substance-related disqualifying conditions are defined as:
Substance abuse means the use of a substance in a situation in which that use was physically hazardous, if there has been at any time in the preceding 2 years:
- A recurrent substance-related legal problem, or
- Continued use despite knowledge of having a persistent or recurrent social, occupational, psychological, or physical problem caused or exacerbated by the substance.
Substance dependence means a condition in which a person is dependent on a substance, as evidenced by:
- Increased tolerance,
- Manifestation of withdrawal symptoms,
- Impaired control of use,
- Continued use despite damage to physical health or impairment of social, personal, or occupational functioning.
If an applicant has a history of substance abuse or substance dependence, the regulation states that the individual does not meet the medical standards unless the FAA determines otherwise through a special issuance process.
This is not discretionary. The FAA is required to apply the law as written.
CFR vs DSM-5: Why This Matters
A common point of confusion is the difference between FAA criteria and modern psychiatric diagnoses.
The DSM-5 uses the diagnosis Alcohol Use Disorder (AUD) or Substance Use Disorder (SUD), classified as mild, moderate, or severe based on a set of criteria. This is a clinical tool designed for diagnosis and treatment planning.
The FAA, however, does not use DSM-5 diagnoses as its primary standard.
Instead:
- The FAA applies CFR definitions, which are behavior-based and risk-based, not diagnosis-based.
- A person can fail to meet FAA medical standards without meeting DSM-5 criteria.
- Conversely, a DSM-5 diagnosis does not automatically determine certification outcome; the FAA makes its own regulatory determination.
This distinction is critical. The FAA’s question is not “Does this person meet DSM-5 criteria today?” The question is: “Has this individual demonstrated behavior consistent with substance abuse or dependence as defined in federal law, and does that behavior pose an unacceptable aviation safety risk?”
When the FAA Gets Concerned — Even Without a Diagnosis
Many pilots are surprised to learn that a formal diagnosis is not required for the FAA to intervene.
Certain events automatically trigger FAA concern because they statistically correlate with substance misuse and relapse risk.
Common examples include:
- A DUI with a blood alcohol concentration (BAC) of 0.15 or greater
- Multiple DUIs, regardless of BAC
- Alcohol-related motor vehicle accidents
- Repeated alcohol-related legal or occupational issues
- Failure to comply with mandated testing or treatment
Why 0.15? Because population-level data show that a BAC at or above this level is strongly associated with impaired control, tolerance, and problematic drinking patterns [4]. From the FAA’s perspective, this raises the possibility of unrecognized dependence, even if the individual has never been formally diagnosed.
In these cases, the FAA will typically require:
- A formal substance abuse/dependence evaluation
- Review by FAA medical officers
This evaluation is designed to determine whether the applicant meets CFR criteria, not whether they “feel fine” or have returned to normal daily life.
There Is a Path Forward: HIMS
A finding of concern is not the end of a flying career.
The FAA has long recognized that substance use disorders are treatable and that pilots may safely return to flight with proper care, accountability, and monitoring.
That pathway is the HIMS program (Human Intervention Motivation Study).
HIMS is a structured FAA-recognized program that includes:
- Appropriate treatment (when indicated)
- Verified abstinence
- Ongoing monitoring and testing
- Oversight by HIMS-trained medical professionals
The goal of HIMS is not punishment. The goal is risk reduction and safe return to flight. Pilots who successfully complete HIMS have an excellent long-term safety record and relapse detection rates that exceed those of the general population.
For pilots willing to engage honestly, follow the program, and commit to sobriety, medical certification is achievable. Like any other significant medical concern, such as Coronary Artery Disease, pilots must pass the evaluations and the monitoring in order to succeed.
We’ll cover the HIMS process, timelines, expectations, and common pitfalls in a future article.
Bottom Line
The FAA’s position on substance abuse and dependence is grounded in safety, data, and federal law—not stigma or outdated thinking. Understanding how the CFR differs from clinical diagnoses, and why certain events trigger scrutiny, can prevent costly mistakes and delays.
If substance use becomes an issue, early recognition and proper management matter. The system is strict—but there is a path forward.
References
[1] M. Oscar-Berman and K. Marinković, “Alcohol: Effects on Neurobehavioral Functions and the Brain,” Neuropsychol. Rev., vol. 17, no. 3, pp. 239–257, Sept. 2007, doi: 10.1007/s11065-007-9038-6.
[2] J. C. Verster et al., “The Alcohol Hangover Research Group Consensus Statement on Best Practice in Alcohol Hangover Research,” Curr. Drug Abuse Rev., vol. 3, no. 2, pp. 116–126, June 2010, doi: 10.2174/1874473711003020116.
[3] W. R. Miller, S. T. Walters, and M. E. Bennett, “How effective is alcoholism treatment in the United States,” J. Stud. Alcohol, vol. 62, no. 2, pp. 211–220, Mar. 2001, doi: 10.15288/jsa.2001.62.211.
[4] D. A. Dawson, “Defining Risk Drinking,” Alcohol Res. Health, vol. 34, no. 2, pp. 144–156, 2011.
