77 is long past the point at which we usually ask people to retire from safety-critical roles. Even when retirement isn't forced, regular evaluation is strongly encouraged for people that old. For instance, consider this statement from the American College of Surgeons:
> Although age-related deterioration varies from individual to individual, gradual decline in overall health, physical dexterity, and cognition generally occurs after the age of 65. For this reason, it is recommended that, starting at age 65 to 70, surgeons undergo voluntary and confidential baseline physical examination and visual testing by their personal physician for overall health assessment. Regular interval reevaluation thereafter is prudent for those without identifiable issues on the index examination. Surgeons are encouraged to also voluntarily assess their neurocognitive function using confidential online tools. As a part of one’s professional obligation, voluntary self-disclosure of any concerning and validated findings is encouraged, and limitation of activities may be appropriate.
