FTL Calculator
Flight Duty Period
Free online FTL calculator for EASA ORO.FTL.205 and FAA Part 117 flight duty period limits. Calculate maximum FDP based on report time and number of sectors, check WOCL encroachment, split duty credits, commander's discretion limits, minimum rest requirements, and augmented crew extensions instantly and at no cost.
EASA & FAA FDP Limits
Calculate maximum Flight Duty Period using the official EASA ORO.FTL.205 Table 2 for acclimatized crew or FAA 14 CFR Part 117 Table B for unaugmented operations. Both regulations supported with accurate lookup tables based on report time and sector count.
WOCL Encroachment Detection
Automatically detects when your flight duty period encroaches on the Window of Circadian Low (02:00–05:59 local time). WOCL encroachment triggers disruptive schedule provisions under EASA FTL and night duty restrictions under FAA Part 117.
Split Duty & Rest Calculation
Calculate split duty FDP extensions with accurate break credit computation. First 90 minutes count in full, remaining break time at 50% per EASA CS FTL.1.220. Minimum rest periods calculated for home base and away from base with extension adjustments.
Augmented Crew Extensions
Support for augmented flight crew with in-flight rest. Calculate extended FDP limits based on rest facility class Class 1 bunk, Class 2 flat seat, or Class 3 reclined seat. Covers both EASA ORO.FTL.205(e) and FAA Part 117 Table C provisions.
EASA ORO.FTL.205 Table 2 Maximum FDP for Acclimatized Crew
| Start of FDP | 1–2 Sectors | 3 Sectors | 4 Sectors | 5 Sectors | 6 Sectors | 7 Sectors | 8+ Sectors |
|---|---|---|---|---|---|---|---|
| 06:00–13:29 | 13:00 | 12:30 | 12:00 | 11:30 | 11:00 | 10:30 | 10:00 |
| 13:30–13:59 | 12:45 | 12:15 | 11:45 | 11:15 | 10:45 | 10:15 | 09:45 |
| 14:00–14:29 | 12:30 | 12:00 | 11:30 | 11:00 | 10:30 | 10:00 | 09:30 |
| 14:30–14:59 | 12:15 | 11:45 | 11:15 | 10:45 | 10:15 | 09:45 | 09:15 |
| 15:00–15:29 | 12:00 | 11:30 | 11:00 | 10:30 | 10:00 | 09:30 | 09:15 |
| 15:30–15:59 | 11:45 | 11:15 | 10:45 | 10:15 | 09:45 | 09:15 | 09:00 |
| 16:00–16:29 | 11:30 | 11:00 | 10:30 | 10:00 | 09:30 | 09:00 | 09:00 |
| 16:30–16:59 | 11:15 | 10:45 | 10:15 | 09:45 | 09:15 | 09:00 | 09:00 |
| 17:00–04:59 | 11:00 | 10:30 | 10:00 | 09:30 | 09:00 | 09:00 | 09:00 |
| 05:00–05:14 | 12:00 | 11:30 | 11:00 | 10:30 | 10:00 | 09:30 | 09:15 |
| 05:15–05:29 | 12:15 | 11:45 | 11:15 | 10:45 | 10:15 | 09:45 | 09:15 |
| 05:30–05:44 | 12:30 | 12:00 | 11:30 | 11:00 | 10:30 | 10:00 | 09:30 |
| 05:45–05:59 | 12:45 | 12:15 | 11:45 | 11:15 | 10:45 | 10:15 | 09:45 |
Note: Values shown are for acclimatized crew members per EASA ORO.FTL.205(b)(1). For crew in an unknown state of acclimatization, the maximum FDP is 11:00 (1–2 sectors), 10:30 (3 sectors), 10:00 (4 sectors), 09:30 (5 sectors), 09:00 (6+ sectors) regardless of start time (Table 3). With FRM implemented, add 1 hour (Table 4).
How to Calculate Flight Duty Period Limits
Select Your Regulatory Framework
Choose between EASA ORO.FTL.205 and FAA 14 CFR Part 117 from the dropdown. Each regulation uses different FDP lookup tables with different time bands, sector columns, and extension provisions. The calculator automatically applies the correct table and rules for your selected regulation.
Enter Report Time and Sector Count
Enter your reporting time at the point of departure in local time (or reference time for EASA). Select the number of planned sectors for the FDP. The calculator looks up your maximum FDP from the regulation's table based on the intersection of your report time band and sector count exactly as published in the EASA CS FTL.1.205 or FAA Part 117 Table B.
Set Acclimatization Status
Under EASA, a crew member is acclimatized to a 2-hour wide time zone band around their reference time for the first 48 hours. If in an unknown state of acclimatization, a reduced FDP table applies. Under FAA Part 117, unacclimated crew face a 30-minute FDP reduction. The calculator applies the correct table or reduction automatically.
Apply Extensions If Applicable
Enable split duty for ground breaks of 3+ hours, or augmented crew for in-flight rest. Under EASA, acclimatized crew may also apply a 1-hour extension (maximum twice per 7 days) with increased rest requirements. Each extension modifies the maximum FDP and recalculates the latest on-blocks time and minimum rest period.
Review Results and Verify Compliance
The calculator displays your maximum FDP, latest on-blocks time, commander's discretion limit, minimum rest period, and earliest next duty time. Check for WOCL encroachment warnings and verify that your planned schedule falls within the calculated limits. Always cross-reference with your operator's Operations Manual as company-specific restrictions may be more limiting than the regulation.
Why Accurate FTL Calculation Matters for Flight Safety
Fatigue Risk Management
Flight Time Limitations exist to manage the cumulative and transient effects of fatigue on flight crew. Fatigue degrades reaction time, decision-making, and situational awareness. Accurate FDP calculation is the first line of defense in every operator's fatigue risk management system.
Regulatory Compliance
EASA ORO.FTL and FAA Part 117 impose hard limits on flight duty periods that cannot be exceeded except under commander's discretion in unforeseen circumstances. Operators must report any FDP exceedance. Non-compliance carries enforcement action, certificate risk, and insurance implications.
Commander's Discretion
Commander's discretion under EASA ORO.FTL.205(f) allows extending FDP by up to 2 hours (or 3 hours with augmented crew) in unforeseen circumstances only. This is not a planning tool it exists for operational disruptions that arise after reporting. Accurate FDP calculation prevents reliance on discretion.
Crew Rest Protection
Minimum rest periods are calculated from the preceding duty period. EASA requires 12 hours at home base or the length of the previous duty, whichever is greater. Extensions trigger additional rest requirements. Proper FTL calculation ensures crew receive adequate recovery time between duties.
Circadian Rhythm Awareness
The Window of Circadian Low (02:00–05:59) represents peak biological sleepiness. FDP limits are reduced for duties that encroach on this window. EASA classifies these as disruptive schedules with additional limits on consecutive early starts, late finishes, and night duties within any 7-day period.
Free FTL Calculator
Professional-grade FTL calculations covering both EASA and FAA regulations at no cost. No registration, no subscriptions instant results with the full FDP reference tables, WOCL detection, split duty credits, augmented crew support, and minimum rest calculation for every duty period.
Understanding Flight Time Limitations Terminology
Duty Period Terms
- Flight Duty Period (FDP): Time from reporting for duty to the end of the last flight (on-blocks) the core regulated period
- Duty Period (DP): All time a crew member is required to work, including FDP plus pre/post-flight duties, training, positioning, and standby
- Block Time (Flight Time): Time from first movement for takeoff to engines off at parking measured chock to chock
- Sector: One takeoff and landing cycle multi-sector days reduce the maximum FDP
- Positioning (Deadhead): Travel as a passenger on company direction counts as duty but not flight time
Rest & Recovery Terms
- Minimum Rest Period: Continuous off-duty time before an FDP 12h at home base (EASA) or 10h (FAA), with 8h uninterrupted sleep opportunity
- Recurrent Extended Recovery Rest (RERRP): 36 hours including 2 local nights, required within every 168-hour period under EASA
- Window of Circadian Low (WOCL): 02:00–05:59 local time the period of maximum biological sleepiness where fatigue risk is highest
- Suitable Accommodation: A bed in a quiet, temperature-controlled room allowing adequate rest required for split duty and layover rest
- Local Night: 8 consecutive hours between 22:00 and 08:00 local time defines rest quality for recovery periods
Extension & Augmentation
- Extension Without In-Flight Rest: EASA allows +1h to basic FDP (max 2x per 7 days) with increased rest requirements for acclimatized crew only
- Split Duty: Break on ground of 3+ hours first 90 min counts in full, remainder at 50%, extending the max FDP by the credit amount
- Augmented Crew: Additional flight crew enabling in-flight rest extends FDP to 14h (Class 3), 15h (Class 2), or 16h (Class 1) under EASA
- Commander's Discretion: Up to 2h FDP extension (3h augmented) for unforeseen circumstances only requires crew consultation and reporting
- Delayed Reporting: If delay < 4h, FDP limit based on original report time. If ≥ 4h, based on the more limiting of original or delayed time
Cumulative Flight Time & Duty Limits (EASA FTL)
Important: This FTL calculator uses the standard EASA ORO.FTL.205 and FAA Part 117 regulatory values. Individual operators may have more restrictive limits defined in their Operations Manual or Individual Flight Time Specification Scheme (IFTSS). Always verify against your operator's approved FTL scheme. This calculator does not replace the operator's duty to maintain FTL records and monitor compliance per ORO.FTL.110 or 14 CFR 117.11.
Frequently Asked Questions About Flight Time Limitations
What is the maximum Flight Duty Period under EASA FTL?
The maximum basic FDP for acclimatized crew under EASA ORO.FTL.205 is 13 hours for 1–2 sectors with a report time between 06:00 and 13:29. This reduces based on the number of sectors (minus 30 minutes per sector from the third onwards, maximum 2-hour reduction) and the time of day. The lowest basic FDP is 9 hours for night duties with high sector counts. Extensions through in-flight rest can increase the FDP to 14–16 hours depending on rest facility class.
What is the difference between FDP and Duty Period?
Flight Duty Period (FDP) starts at the reporting time and ends at on-blocks (engines off) on the last flight. Duty Period includes the FDP plus any post-flight duties, pre-flight duties not part of the FDP, training, positioning, standby, and other duties assigned by the operator. FTL regulations set specific limits on FDP, while duty period limits are typically set by the operator's Operations Manual.
How does acclimatization affect FDP limits?
Under EASA, a crew member remains acclimatized to a 2-hour wide time zone band around their reference time for the first 48 hours. Once in an unknown state of acclimatization, a flat FDP limit applies regardless of start time: 11:00 for 1–2 sectors down to 9:00 for 6+ sectors (without FRM). With FRM implemented, these increase by 1 hour. Under FAA Part 117, unacclimated crew face a 30-minute reduction from the Table B values.
What is the Window of Circadian Low and why does it matter?
The WOCL is defined as 02:00 to 05:59 local time the biological period of maximum sleepiness when the circadian rhythm is at its lowest. Duties that encroach on the WOCL are classified as disruptive schedules under EASA, with additional limits: maximum 4 early starts or 4 late finishes in 7 days, maximum 3 consecutive night duties. The FAA requires rest opportunities during consecutive night FDPs encroaching on the WOCL.
When can a commander use discretion to extend the FDP?
Commander's discretion under EASA ORO.FTL.205(f) applies only to unforeseen circumstances that arise at or after reporting time it is not a planning tool. The commander may extend the basic FDP by up to 2 hours (or 3 hours with augmented crew), must consult all crew members on their alertness, and must submit a report to the operator. The operator must report the discretion use to the competent authority. Under FAA Part 117, similar provisions allow up to 2 hours extension for unforeseen circumstances.
How does split duty work under EASA FTL?
Split duty allows a break on the ground within an FDP, with the break counting as part of the FDP but also providing an FDP extension credit. The break must be at least 3 consecutive hours and the operator must provide suitable accommodation (a bed in a quiet room). The first 90 minutes of the break count in full toward the extension credit, and time beyond 90 minutes counts at 50%. Split duty cannot be combined with in-flight rest or follow a reduced rest period.
What minimum rest is required before an FDP?
Under EASA, the minimum rest at home base is 12 hours or the length of the preceding duty period, whichever is greater. Away from home base, it is 10 hours or the preceding duty, whichever is greater, and must include an 8-hour sleep opportunity plus travel time. If an FDP extension was applied, rest increases by 2 hours (pre and post) or 4 hours (post only). Under FAA Part 117, 10 consecutive hours with 8 uninterrupted hours of sleep opportunity are required.
Does this FTL calculator replace my operator's FTL system?
No. This calculator uses the standard regulatory values from EASA ORO.FTL.205 and FAA Part 117. Individual operators may have more restrictive limits in their Operations Manual or approved Individual Flight Time Specification Scheme (IFTSS). Company-specific restrictions, derogations, and variations always take precedence. Use this calculator for quick reference and cross-checking always verify against your operator's approved FTL scheme before any duty assignment.
What are the cumulative flight time limits?
Under EASA: maximum 100 block hours in 28 consecutive days, 900 block hours in 12 calendar months, 60 FDP hours in 7 consecutive days, and 190 duty hours in 28 consecutive days. Under FAA Part 117: maximum 100 flight hours in 672 consecutive hours (28 days), 1000 hours in 365 calendar days, 60 FDP hours in 168 hours (7 days), and 190 FDP hours in 672 hours. These are hard limits that cannot be exceeded even with commander's discretion.
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