Efforts to improve patient safety have attempted to incorporate aviation industry safety standards. We sought to evaluate the cost and workforce implications of applying aviation duty-hour restrictions to the entire practicing physician workforce.The work hours and personnel deficit for United States residents and practicing physicians that would be created by the adoption of aviation standards were calculated.Application of aviation standards to the resident workforce creates an estimated annual cost of $6.5 billion, requiring a 174% increase in the number of residents to meet the deficit. Its application to practicing physicians creates an additional annual cost of $80.4 billion, requiring a 71% increase in the physician workforce. Adding in the aviation industry's mandatory retirement age (65 years) increases annual costs by $10.5 billion. The cost per life-year saved would be $1,035,227.Application of aviation duty-hour restrictions to the United States health care system would be prohibitively costly. Alternate approaches for improving patient safety are warranted.