The number of hours pilots are allowed to fly per day is regulated by the Federal Aviation Administration (FAA) in the United States. There are limits in place to prevent pilot fatigue, which can compromise safety. The maximum flight time limits depend on a few factors, primarily whether the pilot is flying domestically or internationally, and whether they are part of a single pilot crew or a multipilot crew.
FAA Flight Time Limits for US Domestic Flights
For domestic flights within the US, the FAA has the following daily flight time limits for airline pilots:
- 8 hours for single pilot operations
- 9 hours for multipilot operations
This means on domestic trips, a single pilot can be at the controls for up to 8 hours in a 24 hour period, while pilots on multipilot flights (such as those with a captain and first officer) can be at the controls up to 9 hours.
Rest Requirements
In addition to limiting the hours piloting an aircraft, there are also minimum rest requirements:
- Single pilot flights: Rest period must be at least 9 hours
- Multipilot flights: Rest period must be at least 10 hours
So on domestic trips, pilots must have at least 9-10 hours of rest time each 24 hour period. This is intended to prevent fatigue from impacting safety.
Total Duty Period
There is also a total duty period limit, which includes time on duty in addition to flight time. This is:
- 14 hours for single pilots
- 16 hours for multipilot crews
So while a pilot may only spend 8-9 hours actually flying the plane, when pre and post flight duties are factored in, the total time on duty can be up to 14-16 hours under FAA regulations.
FAA Limits for International Flights
For US pilots operating international flights, the flight time limits per 24 hour period are:
- 8 hours for single pilot
- 12 hours for multipilot crews with augmented crew
- 16 hours multipilot crews without augmented crew
An augmented flight crew means there are extra pilots on board so that the flight crew can take inflight rest. So on long international flights with augmented crews, pilots can be on duty for up to 16 hours and fly for 12 of those hours, with required rest periods.
Total Duty Periods
The FAA also has limits on total time on duty for international flights:
- 14 hours for single pilot
- 18 hours for multipilot crews with augmented crew
- 20 hours for multipilot crews without augmented crew
So for long haul international trips, while flight time may be 12-16 hours with multiple pilots, total time on duty can be up to 20 hours under FAA regulations.
Mandatory Rest Requirements
Minimum rest requirements for international flights:
- 9 consecutive hours of rest for single pilot operations
- 12 consecutive hours of rest for multipilot operations
This ensures pilots get adequate rest between flight duty periods.
FAA Limits on Total Flight Time
In addition to daily limits, the FAA also has restrictions on total flight time during various periods:
- 7 consecutive days – 30 hours for single pilots, 32 hours for multipilots
- Calendar month – 100 hours
- Calendar quarter – 250 hours
- Calendar year – 1,000 hours
So while pilots may fly close to the daily limits at times, their total flight hours are restricted during any 7 day period, month, quarter, and calendar year.
FAA Exceptions and Limitations
There are some exceptions and additional limitations to the FAA flight and duty time rules:
- If standby or reserve status reduces rest time below minimums, the reduced rest time must be added to the next rest period
- Time spent positioning or ferrying an aircraft counts as flight time
- Flight time limits don’t apply to emergency medical evacuations
- Cargo pilots have different limits, up to 15 or 18 hours flight time with augmented crews
- Some additional variations for Alaska flight crews
So while the FAA has detailed flight time limits, there are scenarios where exceptions may apply, such as medical evacuations or cargo operations.
FAA Compliance and Enforcement
Following FAA flight time regulations is mandatory for airlines and pilots operating under FAA jurisdiction. Responsibility for compliance falls both on the pilots themselves and the airline companies.
To ensure compliance, records of pilot flight times, duty periods and rest periods must be meticulously kept and reported by airlines. The FAA has the authority to request and review these records periodically.
If violations are found, the FAA can bring enforcement actions against both individual pilots and airlines. Typical penalties for violations include suspension or revocation of pilot licenses, and fines levied against airlines.
Some past examples of FAA enforcement actions for exceeding flight and duty time limitations:
- American Airlines was fined $7.1 million in 2015
- Southwest Airlines was fined $1.6 million in 2014
- Multiple United Airlines pilots have had licenses revoked for violations
So there are meaningful penalties in place if pilots or airlines fail to comply with FAA duty time regulations.
How Airlines Schedule Pilots Within FAA Limits
Airlines use sophisticated software to schedule flight crews in a manner that maximizes efficiency but complies with FAA limits. Factors considered when constructing pilot schedules include:
- Crew home base airport
- Number of pilots required for aircraft
- Minimum rest requirements between duty periods
- Maximum flight duty periods
- Total flight time limits (monthly, annually etc)
- Individual pilot qualifications and preferences
The goal is to meet FAA time limits while also minimizing downtime between flights and keeping crews near their home base as much as possible. Long international flights require special scheduling such as augmented crews for inflight rest.
Optimization software helps create schedules that satisfy all the constraints while avoiding excessive pilot downtime. Schedules have to be continually readjusted due to operational issues like weather delays.
Typical Pilot Schedules
While every airline pilot’s schedule is different, there are some common patterns that emerge as airlines schedule crews in compliance with FAA limits.
Domestic pilots typically have workdays of around 10-14 hours on duty with scheduled flights of about 6-8 hours. Time between duty periods is at least 9-12 hours to comply with rest minimums. Schedules are usually built around a home base airport.
International pilots have longer duty periods of up to 16-20 hours to complete scheduled flights over 10 hours. Minimum rest requirements mean schedules with several days of flying followed by multiple days off duty.
Here is an example domestic pilot schedule over one month:
| Date | Start Time | End Time | Hours on Duty | Hours Flying |
|---|---|---|---|---|
| 1/1 | 7am | 5pm | 10 | 5 |
| 1/2 | OFF | OFF | OFF | OFF |
| 1/3 | 1pm | 11pm | 12 | 7 |
| 1/4 | OFF | OFF | OFF | OFF |
| 1/5 | 6am | 2pm | 8 | 5 |
| 1/6 | OFF | OFF | OFF | OFF |
| 1/7 | 2pm | 11pm | 12 | 8 |
| 1/8 | OFF | OFF | OFF | OFF |
For longer haul international flying, schedules tend to feature consecutive days on duty followed by multiple days off. Here is an example:
| Date | Start Time | End Time | Hours on Duty | Hours Flying |
|---|---|---|---|---|
| 1/1 | 9am | 11pm | 14 | 10 |
| 1/2 | 10am | 9pm | 13 | 8 |
| 1/3 | 2pm | 7am+1 | 17 | 11 |
| 1/4 | OFF | OFF | OFF | OFF |
| 1/5 | OFF | OFF | OFF | OFF |
| 1/6 | 12pm | 1am+1 | 15 | 12 |
| 1/7 | OFF | OFF | OFF | OFF |
This allows longer flights but maintains compliance with FAA limits thanks to built-in rest periods.
Rest Requirements to Prevent Fatigue
Carefully managed rest time is essential to prevent pilot fatigue. Studies have shown that fatigue slows reaction time, reduces focus, and increases susceptibility to errors.
The FAA duty time limits and required rest periods reflect scientific research into fatigue management. However, responsibility also falls on pilots to effectively use time off duty:
- Get adequate sleep – typically 7-9 hours to fully recover
- Maintain healthy sleep cycles by avoiding light and noise disruption
- Use effective sleep aids if experiencing insomnia
- Eat a balanced diet and exercise regularly
- Avoid alcohol and medications that affect sleep
Well-rested pilots are critical to aviation safety. Those new to the profession may underestimate the rigors of long duty days and cross-country time zone travel. Working with flight surgeons and taking personal action early to establish healthy sleep habits is key.
Impact of Fatigue on Pilots
The impacts of fatigue include:
- Reduced alertness – Fatigued pilots may experience microsleeps or reduced awareness
- Slower cognition and reactions – Processing information and responding to situations is impeded
- Memory problems – Important checklists and procedures may be missed
- Unprofessional behavior – Potential issues controlling temper or inappropriate actions
- Vision changes – Eyesight deteriorates, night vision hampered
Extensive research has quantified the ways both mental and physical performance are degraded by fatigue. Some tragic aviation accidents have been attributed in part to the effects of exhaustion on flight crews.
This is why compliance with FAA flight limits and rest requirements is so critical. Tired pilots make mistakes, so safety depends on recognizing and mitigating fatigue.
Conclusion
The maximum number of hours pilots can fly per day is set by the FAA to ensure safety. Limits depend on the type of operation, but range from 8 hours daily and 30 hours weekly for domestic single pilot flights up to 16 hours daily for unaugmented international crews. Mandatory minimum rest times are also dictated. Airlines use optimization software to construct pilot schedules that extract maximum productivity while complying with FAA regulations. Careful fatigue management through rest requirements, healthy habits, and acknowledgment of risks is necessary to maintain safe skies.