FAA Part 117 FDP Calculator: Max Flight Duty Period

Enter your scheduled report time and number of flight segments to get your maximum flight duty period under FAA Part 117: the Table B limit of 14 CFR 117.13, 30 minutes less when you are not acclimated, and the Table A flight time limit.

Source: 14 CFR 117.13(a) and Table B to Part 117, “Flight Duty Period: Unaugmented Operations” (maximum flight duty period for lineholders); 117.13(b) for crew who are not acclimated (Table B reduced by 30 minutes, based on the local time at the theater in which the flightcrew member was last acclimated); flight time from 117.11 and Table A. 14 CFR Part 117 on eCFR. Not calculated: FDP extensions (117.19), augmented operations (117.17 and Table C, shown below), split duty (117.15), reserve assignments, and any FRMS approved under 117.7.

How to read Table B

Table B gives the maximum flight duty period for a lineholder in an unaugmented operation, that is, with the minimum flightcrew the aircraft requires. Each row is a band of scheduled start times in acclimated time; each column is the number of flight segments, from 1 to 7 or more. No certificate holder may assign, and no flightcrew member may accept, an unaugmented FDP scheduled to exceed it (117.13(a)).

• The longest FDP is 14 hours: a start between 0700 and 1159 with one or two segments.
• The shortest is 9 hours: any start between 0000 and 0359, whatever the number of segments, and the most segments late in the day.
• More segments cost time, but not evenly: for a start between 0600 and 1159, the third segment costs 1 hour and the fifth, sixth and seventh 30 minutes each; between 1700 and 2159, the third, fifth and sixth cost 1 hour each.
• Values are in hours: 12.5 means 12 hours 30 minutes.

Under 117.3, an FDP begins when you are required to report for duty with the intention of conducting a flight, a series of flights, or positioning or ferrying flights, and ends when the aircraft is parked after the last flight and there is no intention for further aircraft movement by the same flightcrew member. Deadhead transportation, training in an aircraft or simulator, and airport or standby reserve count as part of it when they come before a segment, or between segments, without a required rest period in between.

Example 1: an early report with three segments

You are acclimated and scheduled to report at 06:30 for three segments. The 0600–0659 row and the column for 3 segments give 12 hours, so the aircraft must be parked after the third segment by 18:30. With one or two segments the same report gives 13 hours. Table A limits flight time in this FDP to 9 hours, because the report falls between 0500 and 1959.

Example 2: a late report with three segments

You are acclimated and report at 22:30 for three segments. The 2200–2259 row gives 10 hours, so the FDP must end by 08:30 the next morning, and Table A allows 8 hours of flight time for a report between 2000 and 2359. Reporting at 21:30 instead would put you in the 1700–2159 row and allow 11 hours for the same three segments.

Table B: flight duty period, unaugmented operations (scheduled time of start in acclimated time; maximum FDP in hours for lineholders)

The calculator reads this table as it stands on the page and highlights the cell it used. Reserve flightcrew members have their own limits in 117.21.

Acclimated or not

Part 117 reads Table B on the body clock, and it uses two definitions in 117.3 to decide which clock that is:

• Theater: a geographical area in which the distance between the departure point and the arrival point of your flight duty period differs by no more than 60 degrees of longitude.
• Acclimated: you have been in a theater for 72 hours, or have been given at least 36 consecutive hours free from duty. Under 117.25(c), 36 consecutive hours of rest in a new theater make you acclimated there.

If you are not acclimated, 117.13(b) changes two things: the Table B limit is reduced by 30 minutes, and the row is chosen by the local time at the theater in which you were last acclimated, not by the local time where you report. Choose “No, not acclimated” in the calculator and enter the start time on that clock.

Example 3: not acclimated after an eastbound crossing

You are acclimated in New York and fly to Paris, about 76 degrees of longitude east, so Paris is in another theater. After 24 hours there you are scheduled to report at 10:00 Paris time for one segment home. You are not acclimated, so the start is read on New York time, 6 hours behind for most of the year: 04:00. The 0400–0459 row gives 10 hours for one segment, minus 30 minutes: 9 hours 30 minutes. A crew acclimated in Paris reporting at the same moment would have 14 hours. The rule follows the body clock, which still says 04:00.

Table A: flight time limits

Separate from the FDP, 117.11 limits the flight time in an FDP. With the minimum required flightcrew, Table A sets it by the time of report in acclimated time:

With a 3-pilot flightcrew the limit is 13 hours, and with a 4-pilot flightcrew 17 hours (117.11(a)). Flight time runs from the moment the aircraft moves under its own power for the purpose of flight until it comes to rest after landing (14 CFR 1.1). If unforeseen operational circumstances arise after take-off, beyond the certificate holder’s control, the flight time limit and the cumulative flight time limits may be exceeded as far as necessary to land safely at the next destination or alternate airport (117.11(b)); the certificate holder reports it to the FAA within 10 days.

Table C: augmented operations

An augmented flightcrew has more than the minimum number of pilots the type certificate requires, so that each can be replaced at the controls for in-flight rest (117.3). The FDP limit then depends on the start time, the number of pilots and the class of rest facility: class 1 is a bunk or other flat surface in a separate, temperature-controlled compartment where the pilot controls the light and is isolated from noise; class 2, a seat in the cabin that allows a flat or near-flat sleeping position, screened from passengers by at least a curtain; class 3, a seat in the cabin or flight deck that reclines at least 40 degrees and supports the legs and feet.

Table C: flight duty period, augmented operations (scheduled time of start in acclimated time; maximum FDP in hours)

The conditions in 117.17: a flightcrew member who is not acclimated has 30 minutes taken off Table C, read on the local time of the theater where last acclimated; the pilot flying the landing must have 2 consecutive hours of in-flight rest available in the second half of the FDP, and the pilot monitoring the landing 90 consecutive minutes; and an augmented FDP may include no more than three flight segments.

Extending the FDP

Part 117 allows an extension only for an unforeseen operational circumstance: an unplanned event of insufficient duration to allow schedules to be adjusted, such as unforecast weather, an equipment malfunction or an air traffic delay that is not reasonably expected (117.3). The rules differ either side of take-off:

• Before take-off, the pilot in command and the certificate holder may extend the Table B or Table C limit by up to 2 hours, but not if the extension would take you beyond the cumulative FDP limits of 117.23(c) (117.19(a)).
• After take-off, they may extend the FDP as far as necessary to land safely at the next destination or alternate airport, even beyond the cumulative limits (117.19(b)).
• An extension of more than 30 minutes may happen only once before you receive the 30-consecutive-hour rest period of 117.25(b).
• The certificate holder must report to the FAA within 10 days any FDP that exceeded the Table B or Table C limit by more than 30 minutes, with the circumstances.

An extension is a decision for the day, never something to roster. And it does not override fitness: under 117.5 a certificate holder may not keep a flightcrew member on an FDP after the pilot has reported being too fatigued to continue it.

Rest before and between duties

• 10 consecutive hours of rest immediately before any FDP or reserve, measured from release from duty, including an opportunity for 8 uninterrupted hours of sleep (117.25(e)). If you find the rest will not give you that sleep opportunity, you must tell the certificate holder, and you cannot report for the FDP until you have had the full rest (117.25(f)).
• 30 consecutive hours free from all duty within the past 168 consecutive hours before any FDP or reserve (117.25(b)).
• 56 consecutive hours of rest on return to home base after travelling more than 60 degrees of longitude and being away for more than 168 consecutive hours, including three physiological nights’ rest on local time (117.25(d)). A physiological night’s rest is 10 hours of rest that include the hours from 0100 to 0700 (117.3).

During a required rest period, no reserve or duty may be assigned or accepted (117.25(a)): rest is time free from all restraint by the certificate holder, including freedom from present responsibility for work should the occasion arise.

Cumulative limits

Part 117 counts in rolling hours, not calendar weeks or months, so every new duty is checked against the 168 and 672 hours before it. It limits FDP hours, where the EU rules limit all duty; the EASA calculator page has the European figures, and the flight time limitations article in the v1prep Library compares the two schemes.

Frequently asked questions

What is the maximum FDP under FAA Part 117? Table B to Part 117 sets 9 to 14 hours for an unaugmented crew, by the scheduled start in acclimated time and the number of flight segments. A start between 0700 and 1159 allows 14 hours for one or two segments, falling to 11.5 hours for seven or more; a start between 0000 and 0359 allows 9 hours for any number. A flightcrew member who is not acclimated has 30 minutes taken off the Table B limit (117.13(b)).

What does acclimated mean under Part 117? Under 117.3, a flightcrew member is acclimated after 72 hours in a theater, or after at least 36 consecutive hours free from duty. A theater is an area in which the departure and arrival points of a flight duty period differ by no more than 60 degrees of longitude. A crew member who is not acclimated reads Table B on the local time of the theater where last acclimated, and loses 30 minutes.

What is the maximum flight time under Part 117? With the minimum flightcrew, Table A to Part 117 allows 9 hours of flight time for a report between 0500 and 1959 and 8 hours for a report between 2000 and 0459, in acclimated time. A 3-pilot flightcrew may fly 13 hours and a 4-pilot flightcrew 17 hours (117.11). The cumulative limits are 100 hours in any 672 consecutive hours and 1,000 hours in any 365 consecutive calendar days (117.23).

How much rest does Part 117 require? At least 10 consecutive hours before any flight duty period or reserve, including an opportunity for 8 uninterrupted hours of sleep, and at least 30 consecutive hours free from all duty in the 168 consecutive hours before any FDP or reserve. After travelling more than 60 degrees of longitude and spending more than 168 hours away, the rest at home base is at least 56 consecutive hours, including three physiological nights (117.25).

Can a Part 117 flight duty period be extended? Only for unforeseen operational circumstances. Before take-off, the pilot in command and the certificate holder may extend the Table B or C limit by up to 2 hours; after take-off, as far as needed to land safely at the next destination or alternate. An extension of more than 30 minutes may be used only once before a 30-hour rest period, and one exceeding the limit by more than 30 minutes is reported to the FAA within 10 days (117.19).

Does Part 117 apply to cargo pilots? Part 117 applies to flightcrew members in Part 121 passenger operations. A certificate holder may choose to apply it to its all-cargo operations (117.1); otherwise all-cargo flights remain under the older flight time limits and rest requirements in Part 121. The figures on this page are for learning and checking: your certificate holder’s procedures are the ones that apply.