Who you care for
- Airline, military and private pilots, and air crew
- Air traffic controllers and other safety-sensitive staff
- Passengers, including people flying with medical conditions
- Astronauts and commercial spaceflight participants
MedRise MedicineAerospace medicineAerospace medicine: a practical introduction
The medicine of flight and spaceflight: what the specialty does, the physiology every student should know, how pilots are medically certified, and the real routes into the field, from AMSRO in medical school to residency, board certification and becoming an FAA Aviation Medical Examiner.
The specialty
What aerospace medicine is
The American Board of Preventive Medicine describes aerospace medicine physicians as the people who keep those working and traveling in unique, often extreme environments healthy and safe.
Where you work
- The FAA and civil aviation medicine
- Military flight surgeon roles
- NASA and commercial space companies
- Airline medical departments and occupational medicine
Who's in the field
- Board-certified aerospace medicine specialists
- FAA Aviation Medical Examiners from many specialties
- Flight nurses, physiologists and human factors scientists
- AsMA's member groups include NASA flight surgeons, U.S. Air Force flight surgeons and airline medical directors
Physiology that matters
Flight physiology, the essentials
Hypoxia is insidious
As altitude rises, air pressure falls and so does the oxygen your lungs can take in. The FAA's high-altitude advisory circular describes the stages of hypoxia and the time of useful consciousness (how long a person can still act effectively after losing oxygen), and stresses that it varies widely from person to person. The danger is that early hypoxia can feel fine while judgment is already slipping.
The FAA oxygen rule (14 CFR 91.211)
Measured by cabin pressure altitude: above 12,500 feet up to 14,000 feet, the required flight crew must use oxygen for any part of the flight longer than 30 minutes; above 14,000 feet, the crew must use it the whole time; above 15,000 feet, every occupant must be provided with oxygen.
Gas laws inside the body
The same advisory circular walks through the gas laws and trapped-gas problems. As outside pressure drops, gas trapped in the middle ear, sinuses, teeth and gut expands (Boyle's law), which can cause pain. Nitrogen dissolved in tissues can come out of solution as bubbles when pressure falls fast enough (Henry's law), causing decompression sickness.
For your boards: altitude adaptation
Standard physiology that shows up on USMLE Step 1: low oxygen drives hyperventilation and respiratory alkalosis; the kidneys then excrete bicarbonate; erythropoietin and red cell mass rise over days to weeks; 2,3-BPG rises; and hypoxic pulmonary vasoconstriction can lead to pulmonary hypertension over time.
Practice six aerospace medicine cases out loud in MedRise Viva
Beyond the atmosphere
Spaceflight medicine
NASA's Human Research Program groups the dangers of spaceflight into five hazards, and researchers link them to more than 30 human health risks.
The five hazards
- Space radiation
- Isolation and confinement
- Distance from Earth
- Gravity, or the lack of it
- Closed or hostile environments
Bone and muscle
- Bone density drops about 1% to 1.5% a month in microgravity, according to NASA, versus 0.5% to 1% a year for aging adults on Earth
- The loss is greatest in weight-bearing bones: spine, hips and legs
- Muscle wastes without gravity to work against, which is why astronauts exercise daily
Eyes, brain and radiation
- Spaceflight-associated neuro-ocular syndrome (SANS): fluid shifts toward the head and changes in intracranial pressure can affect the eyes and vision
- Outside Earth's magnetic shield, radiation raises cancer risk and can affect the central nervous system
- Longer missions mean longer exposure, so deep-space trips carry more of every risk
Civil aviation medicine
How pilots are medically certified
Pilots get medical certificates from FAA-designated Aviation Medical Examiners. How long a certificate lasts for each kind of flying depends on its class and the pilot's age at the exam (14 CFR 61.23).
| Class | Needed for | Under 40 at the exam | 40 or older |
|---|---|---|---|
| First class | Airline transport pilot, pilot-in-command | 12 months | 6 months |
| Second class | Commercial pilot privileges | 12 months | 12 months |
| Third class | Private, recreational and student pilots | 60 months | 24 months |
After its top-class period runs out, a first- or second-class certificate can still cover lower-class privileges for the rest of the lower class's period. The FAA lengthened the under-40 first- and third-class periods in a 2008 rule.
A door open to many specialties
How to become an FAA Aviation Medical Examiner
You don't need to be an aerospace medicine specialist to be an AME. Once you're licensed, it's a practical way to bring aviation into a family medicine, internal medicine or emergency medicine career.
- Be an MD or DOThe FAA considers applications only from physicians with an MD or DO degree.
- Apply through the FAA's Designee Management SystemQuestions go to the Regional Flight Surgeon's office for your area.
- Finish two online prerequisite coursesMedical Certification Standards and Procedures Training (MCSPT) and Clinical Aerospace Physiology Review for AMEs (CAPAME).
- Attend the Basic AME Seminar in Oklahoma CityA 4 1/2-day seminar; the FAA's 2026 schedule lists three of them, in March, June and September.
- Keep it currentRefresher training every 3 years, with an in-person AME seminar at least every 6 years.
Training
The path to board certification
Residency and the board exam
Board certification in aerospace medicine comes from the American Board of Preventive Medicine after an approved two-year residency and the board exam. The Aerospace Medical Association counts five accredited U.S. residency programs. UTMB, for example, runs a two-year program plus four-year combined aerospace medicine and internal medicine, or aerospace medicine and emergency medicine, residencies, where graduates are board-eligible in both fields. ABEM and ABPM publish joint rules for the combined emergency medicine track.
For international medical graduates
In October 2025 ABPM announced a pathway, approved by the American Board of Medical Specialties, for IMGs who completed a non-ACGME aerospace medicine residency and hold aerospace medicine certification abroad that ABPM accepts. It was set to open in March 2026, so check ABPM's site for the current requirements. ABPM also has other eligibility pathways for physicians already certified in another specialty.
Start now
What a student or resident can do this year
Join AMSRO
The Aerospace Medicine Student and Resident Organization is the Aerospace Medical Association's group for students and residents, from undergraduates to medical residents. If your school has no chapter, you can start one.
Become an AsMA student or resident member
Full-time students and residents get their own membership types. AsMA and its affiliated groups also offer scholarships for students and residents.
Add ASAMS for free
The American Society of Aerospace Medicine Specialists offers free student and resident membership; it requires AsMA membership.
Do a small research project
Hypoxia, fitness to fly with common conditions, or spaceflight physiology all make good student projects. A poster at the AsMA Annual Scientific Meeting is a strong signal on a residency application. The 2027 meeting, held jointly with the Undersea and Hyperbaric Medical Society, is May 23 to 27 at the Hilton Anatole in Dallas: check the abstract deadline on AsMA's site.
Plan your rotations
Ask AMSRO members about aerospace medicine electives, and if you're heading into emergency or internal medicine, look at the combined residency tracks early.
Building a CV for aerospace medicine?
MedRise helps students and IMGs plan research, rotations and applications for competitive paths.
Sources
Where this comes from
- American Board of Preventive Medicine: Aerospace Medicine
- AsMA: Future annual meetings (Dallas, May 23 to 27, 2027)
- Aerospace Medical Association: Careers in aerospace medicine
- AsMA: Membership application and constituent organizations (PDF)
- FAA Advisory Circular 61-107B: Aircraft operations at altitudes above 25,000 feet (PDF)
- 14 CFR 91.211: Supplemental oxygen (Cornell LII)
- NASA Human Research Program: The five hazards of human spaceflight
- Patel et al., npj Microgravity (2020): Red risks for a journey to the red planet
- University of Central Florida: What happens to the human body in space
- Space.com: Five big risks for Mars astronauts (NASA Human Research Program)
- Euronews Health (Apr 11, 2026): How space travel affects the human body
- 14 CFR 61.23: Medical certificates, requirement and duration (Cornell LII)
- Federal Register, July 24, 2008: FAA rule extending first- and third-class durations for pilots under 40
- FAA: Aviation Medical Examiner (AME) designee information
- FAA: Become an AME
- FAA: AME seminar schedule (2026)
- FAA: Guide for Aviation Medical Examiners
- Aerospace Medical Association: Residency programs and related courses
- UTMB: Aerospace medicine residencies
- ABEM and ABPM: Guidelines for combined training in emergency medicine and aerospace medicine (PDF)
- ABPM: Pathway for international medical graduates to become certified in Aerospace Medicine (Oct 29, 2025)
- AsMA: Aerospace Medicine Student and Resident Organization (AMSRO)
- AsMA: Types of individual membership
- AsMA: Students and residents (scholarships and resources)
- American Society of Aerospace Medicine Specialists: Membership
Sources last checked November 14, 2026. Rules, schedules and pathways change: open the official page before you rely on a detail.